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A Timeline of COVID-19 Vaccine Developments in 2021

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If 2020 was dominated by the news of how COVID-19 spread across the globe, then 2021 has so far been focused on ending the pandemic through vaccine distribution.

Note: This timeline will update throughout the year as new developments take place.

March 11 represents the one-year anniversary since the World Health Organization declared COVID-19 a global pandemic, and shortly after, former President Donald Trump had declared a national emergency, with states beginning to issue stay-at-home orders, mask mandates, and capacity limits at businesses like restaurants and bars. For a full look at how the pandemic evolved throughout 2020, see our timeline from last year.

If 2020 was dominated by the news of how COVID-19 spread across the globe, putting normal life on hold for most people and overwhelming health care providers, then 2021 has so far been focused on ending the pandemic through vaccine distribution.

With research into hundreds of vaccine candidates, there are now 3 vaccines approved by the FDA. As of March 10, the CDC was reporting that more than 93.6 million vaccine doses had been administered. Alaska, New Mexico, North Dakota, South Dakota, and Connecticut have administered the most doses per 100,000 of the total population. And with close to 10% of the US population fully vaccinated, updated guidance is starting to roll out.

Here is a look at how vaccine development, approval, and rollout has progressed so far in 2021.

January 4

Operation Warp Speed Initiates Talks With Moderna on Half-Dose Vaccines

Operation Warp Speed official Moncef Slaoui, MD, begins discussions with Moderna and the FDA regarding the possibility of half-dose vaccine regimens so as to double the number of people vaccinated against COVID-19. The announcement comes after data show that two 50-mcg doses of Moderna’s vaccine in individuals aged 18 to 55 years resulted in identical immune responses compared with the standard two 100-mcg doses.

UK Begins Distributing AstraZeneca/Oxford Vaccine

The United Kingdom begins to inoculate its population with the COVID-19 vaccine manufactured by Oxford University and AstraZeneca, which can be stored at refrigerator temperatures between 2° and 8° Celsius, potentially enabling easier distribution. As a result of a highly transmissible variant of COVID-19 spreading throughout the United Kingdom, Prime Minister Boris Johnson hints at upcoming tighter restrictions.

January 5

FDA Advises Against Altering Vaccine Schedules

FDA issues a statement cautioning health care workers against making changes to authorized dosing schedules for approved COVID-19 vaccines. The agency notes that potential changes would be premature and there is not enough evidence of their efficacy compared with approved 2-dose vaccine schedules.

Moderna to Produce 600 Million Vaccine Doses

The company announces it will increase production from 500 million doses to 600 million doses for 2021 and plans to allocate resources to produce 1 billion doses in total this year. At this point, the company has supplied the US government with 18 million doses and projects to make nearly 100 million doses available to Americans by the end of the first quarter of 2021.

January 6

HHS to Provide $22 Billion to Fund Testing, Vaccine Distribution

HHS announces that the CDC plans to provide more than $22 billion in funding for states and territories to support the nation’s COVID-19 response, as a result of the Coronavirus Response and Relief Supplemental Appropriations Act. More than $3 billion of the sum will be made available through the CDC Immunization and Vaccines for Children cooperative agreement.

January 7

CDC: COVID-19 Vaccine Benefits Outweigh Allergic Reaction Risk

Reports of 21 allergic reactions to either the Pfizer/BioNTech or Moderna vaccine among nearly 2 million vaccinated Americans prompt the CDC to announce the incidences should not dissuade individuals from getting vaccinated. Of those who reported incidents, 20 fully recovered while most had a history of such reactions. The statement comes as the CDC anticipates the imminent spread of a highly contagious coronavirus variant, first reported in the United Kingdom, throughout the United States.

Study Shows Patients With Heart Failure Should Be Prioritized for Vaccines

Results of an investigation published in ESC Heart Failure find the risk of death from COVID-19 is reportedly twice as high in patients with acute heart failure. The single-center study indicates these patients should be extra cautious to avoid contracting COVID-19 and ought to be considered a high-priority population as vaccine distribution begins.

January 8

American Hospital Association Pushes for Faster Vaccine Rollout

The American Heart Association (AHA) sends a letter to HHS Secretary Alex Azar stressing that there should have been a universal COVID-19 vaccine rollout. The letter highlights 64 disparate plans being implemented, lack of standardized tasks needed to accomplish delivery, and a failure to provide progress reports compared with plan goals. According to the AHA, to achieve herd immunity 1.8 million individuals need to be vaccinated every day from January 15 through May 31.

Pharmacies Tapped to Distribute Vaccines

Health officials begin to enlist regional and supermarket pharmacies ahead of schedule to address delays in vaccine rollouts, The Wall Street Journal reports. Federal and state officials ask Rite Aid Corp., Kroger Co., Stop & Shop Supermarket LLC, and other retailers to administer vaccines to frontline workers and eligible vulnerable populations weeks before previously planned to troubleshoot protocols.

Biden Plans to Rapidly Release Most COVID-19 Doses

Then–President-Elect Joe Biden announces he will quickly release most available vaccine doses to inoculate more people, reversing Trump’s previous policies, according to the Associated Press. Biden’s plan does not involve cutting 2-dose vaccines in half but accelerating shipments of first doses instead of holding second doses in reserve.

States Face Significant Rollout Hurdles

States and local health departments struggle to implement mass vaccination programs while facing a surge in COVID-19 cases and record-breaking hospitalizations, TIME reports. Staff shortages and shrinking budgets complicate efforts to receive, store, distribute, track, and administer vaccines, as well as monitor individuals for adverse events.

January 11

Vaccine Doses Go Unused or Are Trashed

Biden’s goal remains 100 million vaccinations in 100 days, and he pledges to release all available doses, reversing Trump’s decision to hold back doses to ensure that second shots were available for those who had already received their first Pfizer/BioNTech or Moderna dose—at this point, the only approved COVID-19 vaccines. Rollout has been chaotic, as the CDC relegated responsibility to states to determine vaccination priority and extra doses built up in freezers or were trashed due to regulation confusion.

January 12

CDC, HHS Update Vaccine Allocation Guidance

Then–HHS Secretary Alex Azar announces that forthcoming COVID-19 vaccine supplies will be based on to-this-point administration rates and each state’s total population of residents who are 65 years and older—but states have only 2 weeks to prepare. Vaccine rollout continues to be bumpy, and this update aims to address some of the issues hindering access to higher-risk individuals—health care and frontline workers, and those with comorbidities—with states possibly receiving fewer doses from lack of data reporting. All available vaccine doses are released, and distribution expands to pharmacies and community health centers.

January 14

Elderly Los Angeles County Residents Report Confusion, Delays

Conflicting messages from California Governor Gavin Newsom and local health officials lead to floods of phone calls and crashing websites inundated with appointment requests. While the governor said that Los Angeles County residents 65 and older were eligible to receive a COVID-19 vaccine, health officials reiterated that the group still has to wait. At this point, the city is in phase 1A of rollout (health care workers, skilled nursing and long-term care facility residents), and phase 1B eligibility (which includes people over age 65) is not slated to open until early February.

GoodRx Report Documents Vaccine Deserts

Limited pharmacy access, or living in a “pharmacy desert,” is predicted to affect access to available vaccines, with low pharmacy density—the national average is just 1.83 pharmacies per 10,000 people—translating to more competition for fewer appointments and rural and urban areas alike being affected. At the time of this report, the authors predict that 423 counties had capacity to vaccinate only up to 10% of their combined populations and 177 had zero capacity because they didn’t have any pharmacies. Officials continue to sound the call for more mass vaccination sites and supportive infrastructure.

January 18

Reports of Racial Disparities in Vaccination Rates

Ethnic and racial minorities continue to be disproportionately affected by the pandemic, with a Kaiser Health News report showing Black Americans being vaccinated at rates 2 to 3 times below White Americans. COVID-19–related mortality, meanwhile, remains 3 times greater in Black, Hispanic, and Native American populations. Top reasons for these disparities, including among health care workers, are lack of access (ie, to technology and vaccines) and mistrust of the vaccine.

January 19

California COVID-19 Variant May Be Vaccine Resistant

Following genetic sequencing, researchers report that current vaccines may not be strong enough against the L452R variant, first identified in Denmark in March 2020 before surfacing in California in May. Prevalence of this variant is growing, with 1 comparison showing a jump from 3.8% of samples tested in late November to early December 2020 to 25.2% of samples tested in late December 2020 to early January 2021.

Pfizer, Moderna, AstraZeneca to Test Vaccines in Adolescents

With current vaccines still prioritized for older Americans and those with underlying heath conditions, as well as health care workers, the 3 pharma giants reveal their testing plans for younger Americans. Moderna is testing doses among 12- to 18-year-olds, Pfizer is said to have recruited 12- to 15-year-olds, and AstraZeneca and Oxford University report wanting to compare outcomes among 6- to 11-year-olds and 12- to 18-year-olds.

Incoming CDC Director Walensky to Prioritize Vaccine Rollout

Rochelle Walensky, MD, MPH, the soon-to-be 19th director of the CDC, pledges to increase science-based communication in an effort to address vaccine hesitancy and antivaccination sentiment. Vaccine rollout continues to vary widely among states, and Walensky pledges to increase both vaccination sites and those administering doses to overcome these disparities, especially in harder-to-reach areas.

January 20

Novavax Reports Trial Dropouts

Elderly individuals are requesting “unblinded” status in Novovax’s COVID-19 vaccine trial to see if they were administered a placebo and are eligible to receive the already-approved Pfizer/BioNTech or Moderna vaccine. Novovax’s phase 3 trial, which had a goal of 30,000 participants, has already been delayed by manufacturing lags despite a $1.6 billion infusion from Operation Warp Speed in July 2020. Accelerated expanded eligibility is also hindering recruitment of new trial enrollees.

California Reports Allergic Reactions to Moderna Vaccine

After vaccinations were paused on January 19 at a San Diego vaccination center due to a spate of allergic reactions possibly related to lot 041L20A of Moderna’s COVID-19 vaccine, they are allowed to resume by the California Department of Public Health. The move follows discussions among allergy and immunology specialists, the CDC, the FDA, Moderna, and the County of San Diego Department of Public Health. This batch contained more than 1 million doses that were distributed to almost 1700 vaccination sites in 37 states, and California received 330,000-plus of these doses for 287 providers.

January 21

Pfizer Vaccine Effective Against United Kingdom’s B117 Variant

Research from Pfizer and BioNTech indicates that the companies’ COVID-19 vaccine works just as well against a highly transmissible coronavirus variant, B.1.1.7, first discovered in the United Kingdom. Effectiveness against COVID-19 variants originating from South Africa and Brazil continue to be investigated, with experts noting that updated immunizations may be explored if the virus picks up enough significant mutations impacting the vaccines’ efficacy.

Amazon Offers to Help Distribute Vaccines

To assist Biden’s goal of vaccinating 100 million Americans against COVID-19 in his first 100 days in office, Amazon sent a letter to the president offering to help by leveraging the company’s operations, information technology, and communications capabilities. Since then, Biden updated his goal to 150 million doses in 100 days.

January 22

New Data Shows Moderna Vaccine Can Induce Rare Anaphylactic Reactions

According to data by the CDC, Moderna’s COVID-19 vaccine induces rare anaphylactic reactions in a small number of people, similar to that found in recipients of the Pfizer/BioNTech vaccine. Reported by STAT, the CDC estimated a prevalence of 2.1 cases of anaphylaxis per million doses of the Moderna vaccine and 6.2 cases per million doses of the Pfizer vaccine.

January 25

Fauci: Vaccine Neutralizing Antibodies Lessened by Variants, but Still Likely Effective

The nation’s top infectious disease expert, Anthony Fauci, MD, head of the National Institute of Allergy and Infectious Diseases (NIAID) said that current COVID-19 vaccines may be less effective against more contagious variants first identified in South Africa, the United Kingdom, and Brazil, although they will still likely provide enough protection.

Health Officials Nationwide Report Limited Vaccine Supply

State and local health officials nationwide are reporting limited vaccine supply, which CDC Director Rochelle Walensky, MD, MPH, said will hopefully be increased after the Biden administration’s first 100 days. Walensky further noted that the federal government can't be certain of the current size of the vaccine supply, an issue she attributed to challenges presented by the Trump administration’s vaccine rollout.

Merck Ends Development of 2 Potential COVID-19 Vaccines

Following poor results in early-stage studies, Merck ceased development of 2 potential COVID-19 vaccines, with efforts instead focused on assessing the efficacy of 2 treatments for COVID-19 not yet approved by regulators. One of the treatments, MK-7110, has the potential to minimize the effects of an overactive immune response to COVID-19. The US government is paying Merck about $356 million to fast-track production of the potential treatment.

January 26

Moderna to Develop Booster Shots to Combat Variants

Moderna will test 2 COVID-19 booster shots designed to be more effective against emerging variants, with one targeting the South African variant and the other to fight new mutations. The move comes amid reports that its approved vaccine was less potent against the variant identified in South Africa.

January 27

US Vaccine Supply to Increase by 50%

The Biden administration plans to purchase 200 million more COVID-19 vaccine doses to be delivered through the summer, adding to the 400 million doses already manufactured. Vaccine distribution to states additionally increased from 8.6 million to 10 million, a 16% bump in doses.

Sanofi Grants BioNTech Access to a Germany Plant to Boost EU Supply of Vaccine

As Sanofi’s expected delivery date of its COVID-19 vaccine was delayed to summer 2021, the company granted BioNTech access to a Frankfurt, Germany, plant in order to boost the European Union supply of its COVID-19 vaccine by more than 125 million doses.

January 29

Johnson & Johnson, Novavax Release Positive Phase 3 Trial Data

Both Johnson & Johnson (J&J) and Novavax announce positive results of phase 3 trials demonstrating the efficacy of each company’s respective COVID-19 vaccine. The 1-shot vaccine by J&J is 72% effective in the United States and 66% effective overall at preventing moderate to severe COVID-19. The 2-shot Novavax vaccine had 89% efficacy in a United Kingdom trial. Notably, the efficacy of both vaccines is lessened against the highly transmissible B.1.351 variant from South Africa.

February 1

More Americans Vaccinated Than Infected With COVID-19

The United States reaches a milestone as more Americans are reported to have received at least 1 dose of a vaccine against COVID-19 than have tested positive for the virus. Administering vaccine shots at a faster rate than any country worldwide, the United States had administered 26.5 million vaccinations, compared with the 26.3 million people that have tested positive nationwide since January 20, 2020.

February 3

GlaxoSmithKline to Partner With CureVac to Accelerate COVID-19 Vaccine Production

The companies will produce 100 million additional doses of GlaxoSmithKline’s COVID-19 vaccine, which is in a phase 2 trial, plus they will work together to produce a new vaccine to target variants of the virus.

Oxford/AstraZeneca Announce Results of Vaccine

Updated data show that the vaccine from Oxford University and AstraZeneca is 76% effective at 3 months after just 1 dose. Antibodies remain consistent over 3 months and a booster dose at that time increases the efficacy to 82.4%. Phase 3 trials are underway in the United Kingdom and South Africa. If the vaccine is approved, the booster dose will be delivered 12 weeks after the initial shot.

February 4

British Study Will Test Mixing AstraZeneca, Pfizer Vaccine Doses

Current guidelines require 2 doses of the same COVID-19 vaccine, but a British study is testing the safety and efficacy of one shot of the AstraZeneca vaccine followed by a Pfizer dose and vice versa. The goal is to see if, in the event that the same vaccine is not available for the second dose, vaccines can be mixed.

February 5

J&J Submits COVID-19 Vaccine for Emergency Use Authorization

The J&J vaccine, which would be the third to enter the US market, was submitted to the FDA and the company requests that the agency issue an emergency use authorization (EUA). The J&J differs from the other, already-approved vaccines in that it is a single shot. The J&J vaccine can be stored for up to 3 months in regular refrigerated temperatures.

February 8

South Africa Suspends Use of AstraZeneca Vaccine

Preliminary data from a small study show that the AstraZeneca vaccine offers minimal protection against mild to moderate disease caused by the B.1.351 variant. The country had already received 1 million doses of the vaccine, but it is now transitioning to the J&J vaccine for frontline workers.

February 9

CanSino Reports Single-Shot Vaccine Efficacy Data

The 1-shot vaccine from CanSino Biologics is 66% effective against symptomatic cases and 91% effective against severe cases of COVID-19. In comparison, the J&J single-shot vaccine is 66% effective at preventing moderate to severe cases.

Pfizer/BioNTech mRNA Vaccine Neutralized 3 COVID-19 Variants

The vaccine neutralized the strain that first appeared in the United Kingdom, as well as 2 variants the were first confirmed in South Africa. The vaccine is 95% effective against the original virus. Neutralization of the variants from South Africa was slightly lower than the variant from the United Kingdom.

February 12

United States Purchases 200 Million Moderna, Pfizer Vaccines

The Biden administration announces the purchase of 200 more million doses of Moderna and Pfizer vaccines, bringing the country’s total purchase at this point to 600 million, or enough to vaccinate 300 million people.

February 15

Polls Show Split by Party Line Over Vaccine Uptake

Polls begin to show vaccine hesitancy splitting along party lines, with Democrats more likely than Republicans saying they are willing to receive a COVID-19 vaccine. In 2 separate polls, only 51% of Republicans indicated that they had been vaccinated or wanted to do so, compared with 91% of Democrats (as polled by CNN) or 74% (as polled by Axios/Ispos).

February 17

Storms Stall Vaccine Shipments, Cancel Immunization Drives

Deadly winter storms across the country impede the national vaccine rollout with shipments being halted from facilities in Tennessee and Kentucky and immunization drives canceled in multiple states, including Pennsylvania, Illinois, Tennessee, and Missouri. At this point, the United States is administering 1.7 million doses a day.

February 19

Pfizer/BioNTech First Dose Effective in Real-World Data

A study from Israel shows that the first dose of the Pfizer/BioNTech vaccine is 85% effective 15 to 28 days after it is given, according to real-world data from Sheba Medical center. The report involving 9000 individuals, also suggests that lower-than-approved temperature and storage temperatures are possible.

US Pledges $4 Billion to Global Vaccine Effort

The Biden administration pledges $4 billion in funding for Gavi, the Vaccine Alliance, the global vaccine effort that counts The World Health Organization and the Coalition for Epidemic Preparedness Innovations as partners. The plan would release $2 billion first, followed by another $2 billion over 2 years.

6 Million Vaccine Doses Stalled by Winter Weather

The White House confirms that the mid-month winter storms created havoc in getting 6 million vaccine doses out to all 50 states. Doses were held back rather than losing them to sites that lacked power to store them at correct temperatures. The administration asked immunization sites to expand their capabilities to make up for the delays.

New Guidance for Disease-Modifying Therapy Dosing Adjustments for Vaccines

The Multiple Sclerosis Society releases guidance for disease-modifying therapy (DMT) dosing adjustments for COVID-19 vaccines in patients with stable disease. The society emphasized that both of the 2 mRNA vaccines are safe and release suggestions for optimal timing of the vaccines based on the specific DMT.

February 21

Pfizer Vaccine 98.8% Effective Against Deaths, Hospitalizations After 2 Doses

More data from Israel show that the Pfizer vaccine, at 2 doses, is 98.8% effective at preventing deaths and hospitalizations. About a third of the country has been vaccinated at this point, but vaccinations in Palestinian-held territories lag.

February 23

FDA Recommends Expedited Trials for COVID-19 Booster Shots

The FDA says it will expedite trials examining vaccine booster shots against variants of COVID-19 and will not require large clinical trials of the new shots’ efficacy compared with placebo. The move is an effort to fast-track booster doses amid the emerging threat of variants from South Africa and the United Kingdom.

Single Pfizer Vaccine Cuts Death, Hospitalization Rates

English and Scottish data show 1 dose of the Pfizer vaccine appears to slash hospitalization and death rates by 75%. In those over the age of 80, 1 dose provided 57% efficacy at preventing symptomatic COVID-19 after 3 to 4 weeks.

February 24

Tennessee Department of Health Finds Wasted Vaccine Doses

An investigation conducted by the Tennessee Department of Health (DOH) uncovered a breadth of issues related to COVID-19 vaccine distribution. The Associated Press reports that more than 2400 doses went unused in the state’s largest county in February alone, which the DOH attributed to winter storms, and local officials sat on tens of thousands more. Hospital partners and city officials in Memphis took over vaccine distribution.

Flu Vaccination May Offer Some Protection Against COVID-19

A study published in the American Journal of Infection Control found that patients who had received an influenza vaccine had 24% lower odds of testing positive for COVID-19. Patients vaccinated against influenza who did test positive for COVID-19 were more likely to have better clinical outcomes.

February 25

Los Angeles Vaccine Distribution Program Misused

Special access codes for vaccine scheduling intended to improve access to COVID-19 vaccines among hard-hit communities of color in California were misused by outsiders, according to The Los Angeles Times. The codes, which were provided to community organizations in largely Black and Latino communities, were reportedly circulated among wealthier residents who worked from home in Los Angeles and were not yet eligible for vaccines.

Pfizer/BioNTech Vaccine’s Efficacy Is Underscored by Real-World Data

An independently reviewed real-world study shows that 2 doses of the Pfizer/BioNTech COVID-19 vaccine reduced symptomatic cases by 94% across all age groups, Reuters reported. The study, which used evidence from Israel 2 months into one of the fastest vaccine rollouts worldwide, also found that a single shot was 57% effective in protecting against symptomatic infections 2 weeks after vaccination.

February 26

Vaccine Acceptance Among Americans Increases

According to the KFF COVID-19 Vaccine Monitor, 55% of US adults say that they had either already received at least 1 dose of the vaccine or that they would get vaccinated once it became available (18% and 37%, respectively). The findings show a significant increase from 34% overall acceptance in December and 47% in January. The percentage of people who say they would rather wait to see how others fared before receiving a vaccine themselves dropped from 31% in January to 22% in February.

50 Million COVID-19 Vaccine Doses Administered

Just days after the United States hit a grim milestone of half a million lives lost to COVID-19, the Biden administration announces a more positive milestone: 50 million doses of COVID-19 vaccines administered within 5 weeks after inauguration day. This has the administration on pace to exceed Biden’s goal of administering 100 million shots within his first 100 days in office.

FDA Permits Standard Freezer Storage for Pfizer/BioNTech Vaccine

The FDA approved storing Pfizer/BioNTech’s COVID-19 vaccine in standard freezer temperatures for up to 2 weeks rather than the previously required –112° F to –76° F to help ease delivery and storage, according to The Hill. Pfizer had applied to the FDA for the relaxed requirement based on the results of studies to determine safe storage temperatures.

FDA Panel Votes to Move J&J’s COVID-19 Vaccine Forward

An FDA advisory panel unanimously votes to move the J&J COVID-19 vaccine forward, bringing it 1 step closer to an EUA. Phase 3 trial data shows the vaccine to be effective against common COVID-19 strains and emerging variants in the United States and South Africa.

Israel Reaches a Vaccination Milestone

Israel becomes the first country to have vaccinated half of its population, a major milestone on the road to herd immunity, Bloomberg reports. The overall rate of infection slows, as does the rate of critically ill COVID-19 patients in hospitals. Nearly 3.3 million people have received 2 doses of the Pfizer/BioNTech vaccine.

February 27

FDA Grants EUA for J&J Vaccine

The FDA grants an EUA to J&J for distribution of the nation’s third COVID-19 vaccine. The Vaccines and Related Biological Products Advisory Committee votes unanimously that the benefits of the vaccine outweighed the risks in those 18 years and older.

March 1

J&J Vaccine Rollout Begins

Just 2 days after receiving the EUA, J&J announces that the first batch of its vaccine would be sent to states and pharmacies to distribute to the public. The company says that it plans to distribute 3.9 million doses to state and local governments based on the size of their adult populations.

Fauci: Pediatric Vaccine Rollout Likely to Begin in Early 2022

Fauci says that he predicts elementary school-aged children will have access to COVID-19 vaccines either in late 2021 or during the first quarter of 2022. Additionally, he says that high school students will likely have access around the beginning of the new school year in the fall. Studies are currently underway to assess the safety and efficacy of COVID-19 vaccines in children.

Former President and First Lady Received COVID-19 Vaccines in January

A Trump advisor confirms that former President Donald Trump and First Lady Melania Trump received COVID-19 vaccines in January prior to their departure from the White House. The revelation came shortly after the former president recommended in a speech for his followers to get vaccinated.

March 2

Merck Will Aid J&J in Vaccine Production

Biden says that Merck and J&J are partnering to increase production of J&J’s COVID-19 vaccine. When the FDA granted the EUA to J&J, the supply of doses was limited. The partnership with Merck is supposed to help address the shortages.

Fauci Advises the United States to Stick With 2-Dose Regimen

Fauci advises against administering just 1 dose of a 2-dose vaccine in order to distribute more vaccines to more people, warning that shifting to a single-dose strategy may leave people less protected and at a higher risk for certain COVID-19 variants.

March 3

Biden Says Vaccines Will Be Available for Every US Adult by May

Biden says that every US adult will have access to a COVID-19 vaccine by the end of May. The administration plans to invoke the Defense Production Act to accelerate J&J’s vaccine production. The president also calls for every state to ensure that teachers, child care providers, and school staff receive at least 1 dose by April.

March 4

Lack of Pharmacies in Rural America Could Impede Rollout

A lack of brick-and-mortar pharmacies in rural areas of the United States could hinder COVID-19 vaccine rollout. There are more than 100 counties in the country that do not have a pharmacy, potentially leaving thousands of people without easy access to a vaccine and forcing them to drive long distances for an available dose. Access may be further impeded by difficult weather or road conditions.

Rich Florida Residents Receive Vaccines Before Rest of the State

Most of the wealthy residents aged 65 and older living in a gated community of the Florida Keys were inoculated against COVID-19 by mid-January while many of the state’s eldest residents continue to struggle to get their first dose. Although it’s unclear how the community received so many vaccines before the rest of the state, The Ocean Reef Club is home to many donors for the Florida Republican Party and GOP candidates, including current Governor Ron DeSantis.

March 5

Local Delayed Skin Reactions Reported After Moderna Vaccine

A small number of people who received Moderna’s COVID-19 vaccine experienced delayed, large, localized skin irritations around the injection site. Although the symptoms were reported to have cleared up in a median of 8 days, physicians should be made aware about the potential adverse effect in order to navigate proper treatment and guidance, according to researchers.

March 8

CDC Releases Guidance on Safe Activities for Fully Vaccinated Individuals

People who have received both doses of the 2-shot vaccines or are 2 weeks out from the single dose of the J&J vaccine may resume some activities in private, according to guidance from the CDC. The agency says that vaccinated individuals can meet with other vaccinated individuals or low-risk unvaccinated individuals from one other household in a private setting without masks or distancing. However, masks and distancing are still recommended when meeting unvaccinated individuals at high risk, with members of multiple households, or when in public.

March 9

Pfizer Vaccine Neutralizes the Brazil Variant

The vaccine from Pfizer and BioNTech neutralizes the COVID-19 variant spreading throughout Brazil. The variant is more contagious and reinfects people who have recovered from other versions of the virus. Pfizer will test a third booster shot to combat the South African variant.

March 10

Alaska Removes COVID-19 Vaccine Eligibility Restrictions

Anyone living or working in Alaska who is 16 years or older is now eligible to receive a COVID-19 vaccine, making it the first state to remove eligibility requirements. The newly eligible 16- to 18-year-olds are restricted to receive only the Pfizer/BioNTech vaccine, as vaccines from J&J and Moderna have only been approved for people 18 and older. Nearly one-fourth of residents have received at least 1 dose.

March 11

100 Million More Doses of J&J Vaccine Ordered

Biden orders an additional 100 million doses of the single-dose J&J vaccine to safeguard against the spread of COVID-19 variants and prepare for potential pediatric vaccinations, The Washington Post reports. The United States has now ordered a total of 200 million J&J doses, although the new order is not expected to be filled until the second half of 2021.

Denmark, Norway, Iceland Suspend Use of AstraZeneca Vaccine

Health authorities in Europe suspend use of the AstraZeneca vaccine as a precaution after concerns that it may increase the risk of blood clots. There is no evidence of any causal link, and in the vast majority of cases such illnesses have nothing to do with the shots, according to The New York Times.

Nearly Half of Republican Men Will Not Get COVID-19 Vaccines

A PBS NewsHour/NPR/Marist poll finds 49% of Republican men say they have no plans to get COVID-19 vaccines, The Hill reports. The survey was conducted among 1227 US adults between March 3 and March 8. In comparison, 87% of Democrats surveyed said they have already received the vaccine or plan to when it becomes available.

Biden Pushes for Expanded Vaccine Eligibility

In his first prime-time address as president, Biden instructs states to make vaccines available to all adults 18 years and older by May 1. Biden also says the possibility of returning to a semblance of normal life could be achieved by Independence Day if Americans continue to practice mitigation efforts like mask wearing and social distancing.

March 12

Novavax, Pfizer Release New Vaccine Efficacy Data

Data from Novavax Inc show the company’s COVID-19 vaccine is 96% effective against the original version of SARS-CoV-2 and 86% effective against the more contagious variant first detected in the United Kingdom. In addition, a study using real-world evidence of the Pfizer/BioNTech vaccine found it is 97% effective against symptomatic COVID-19—offering more protection than previously thought.

March 14

AstraZeneca Refutes Reports Linking Its Vaccine to Blood Clots

The company issues a statement saying there is no scientific evidence for the association despite countries’ halting use of the vaccine. At this time, the vaccine has been administered to 17 million people worldwide with 15 cases of deep vein thrombosis and 22 pulmonary embolisms reported—rates the company says are lower than expected.

Fauci: Trump Should Encourage Supporters to Get Vaccinated

Fauci urges Trump to encourage his followers to get the COVID-19 vaccine, CBS News reports. Appearing on “Fox News Sunday,” Fauci says that should Trump decide to do so, “It would make all the difference in the world.”

March 15

White House to Spend $1.5 Billion on Vaccine Confidence Campaign

The Biden administration is poised to unveil an expansive public relations campaign aiming to boost confidence in approved COVID-19 vaccines and increase uptake nationwide. The campaign will focus on addressing skepticism on vaccines’ safety and efficacy among young people, people of color, and conservatives via television, radio, and digital advertising.

More European Countries Pause Use of AstraZeneca Vaccine

Germany, Portugal, Slovenia, France, Spain, Italy, Ireland, and the Netherlands join other European nations in suspending use of the vaccine over blood clot concerns, CNBC reports. Both the World Health Organization and United Nations health agencies have urged nations to continue using the vaccine.

Experts Stress No Causal Link Between AstraZeneca Vaccine and Blood Clots

Health officials repeat no causal link has been identified between the vaccine and blood clots and note European countries’ suspensions might do more harm than good, according to NBC News. Experts agree that without a high burden of proof, suspensions may drive future outbreaks across Europe.

March 16

Evidence Underscores Need to Vaccinate Those With Compromised Immune Systems

Data show that variants of COVID-19 likely evolved in individuals with weak immune systems, such as those with cancer or other conditions, emphasizing the need to vaccinate these individuals as soon as possible. Scientists believe that as the virus infects someone with a weak immune system, the host allows it to adapt and evolve for months before being transmitted to others. In most people, an infection only lasts about a week, which is not long enough for the virus to acquire more than 1 mutation, if any.

Adm Brett Giroir Urges Trump to Encourage Followers to Get Vaccinated

Former coronavirus testing czar Adm Brett Giroir encourages Trump and former Vice President Mike Pence to tell supporters to get vaccinated. That night, Trump appears on Fox News and urges his followers to get vaccinated, saying the vaccine is safe and effective, the Associated Press reports.

March 17

Vaccine May Lessen COVID-19 Long-Haul Symptoms

Anecdotal evidence indicates that among the 10% to 30% of COVID-19 cases that produce long-lasting symptoms, these symptoms are dissipating in some vaccinated patients. According to the NIH, these reports may be the result of the placebo effect or hidden coronavirus reservoirs could be enabling such reactions.

KFF Data Show Racial Disparities in Vaccine Distribution

Data from the Kaiser Family Foundation (KFF) show a consistent pattern across states of Black and Hispanic individuals receiving smaller shares of vaccinations compared with proportions of cases and deaths in these communities and their proportion of the total population. In comparison, White individuals receive a greater share of vaccines compared with their proportion of cases, deaths, and total population among most states reporting data.

CDC: High Vulnerability Counties Have Lower Vaccination Coverage

Using the social vulnerability index, researchers find that in the first 2.5 months of state vaccine rollouts, vaccination coverage was lower in high vulnerability counties nationwide. Authors note that further efforts are needed to increase vaccine coverage in these counties, as the residents are disproportionately affected by the pandemic.

Vaccine Doses Expected to Reach 700 Million by Summer

Increased production of the 3 approved COVID-19 vaccines by manufacturers is expected to boost the supply of available doses to 700 million by this summer, NBC News reports. At this point, around 39 million people in America (12%) have been fully vaccinated. The Pfizer/BioNTech partnership is expected to produce 120 million doses by the end of March, with 80 million more slated for the end of May.

March 18

European Medicines Agency: AstraZeneca Vaccine is Safe

The European Medicines Agency (EMA) announces that AstraZeneca’s COVID-19 vaccine is safe after a review of millions of cases concluded it does not increase the overall risk of blood clots. The agency notes there are still uncertainties and will add a warning label to the vaccine so medical professionals can monitor for a potential rare complication leading to blood clots and bleeding in the brain.

US to Send Excess AstraZeneca Vaccines to Mexico, Canada

Biden announces Mexico will receive 2.5 million doses of the already-produced AstraZeneca vaccine and Canada will receive 1.5 million doses. The vaccine is not yet approved in the United States. Currently, the United States has 7 million doses ready to distribute and the plan is not expected to impact the president’s mission to make vaccines available to all US adults by May.

Efficacy of AstraZeneca, Pfizer Vaccines Against Variant First Identified in Brazil

A COVID-19 strain first identified in Brazil may be less resistant to natural- and vaccine-induced antibodies than first feared, according to a press release from the University of Oxford. Study results, published before publication, show antibodies among those who received the AstraZeneca or Pfizer/BioNTech vaccine were able to neutralize the P1 strain at a rate similar to the B117 variant, first identified in the United Kingdom.

UK Model Finds Vaccination Alone Won’t End Pandemic

Using epidemiological data from the United Kingdom and estimates of vaccine efficacy to predict the long-term dynamics of the COVID-19 pandemic, researchers find that vaccination alone is insufficient to contain the outbreak. They conclude that success is highly contingent on specific vaccine properties and population uptake.

March 19

United States Administers 100 Millionth Vaccine

The United States reports it has administered 100 million COVID-19 shots, more than a month before Biden’s target date of his 100th day in office, the Associated Press reports. Currently, the country administers around 2.5 million doses each day. The president is expected to announce a new vaccination goal next week.

Patients With Blood Cancer Report Vaccine Hesitancy

Survey results show around 30% of individuals with blood cancer are hesitant to receive a COVID-19 vaccine, and these individuals are less likely to engage in self-protective behavior. Findings are striking as patients with leukemia and lymphoma are more likely than those with other cancers to suffer severe complications or die from COVID-19.

March 22

AstraZeneca Reports Its Vaccine Is 79% Effective

The company releases data from a US clinical trial highlighting the vaccine’s efficacy and reporting no safety concerns. Efficacy was similar across all groups and the company announces it hopes to apply for an EUA in the first half of April. Should the vaccine be approved, the company will deliver 20 million doses immediately and another 20 million throughout the first month of approval.

March 23

US Data Safety Monitoring Board Questions AstraZeneca Data

The independent committee overseeing AstraZeneca’s US COVID-19 vaccine trial expresses concern the company has reported outdated data. The Data Safety Monitoring Board (DSMB) feels the reported data created an incomplete view of the vaccine’s efficacy.

European Union Could Cut Vaccine Supply

Despite a potential third surge of COVID-19, the European Union drafts legislation reducing its export of vaccines manufactured among member countries. Under the legislation, the reduction would stay in place for 6 weeks and block shipments to countries with higher vaccination rates than the Union.

J&J May Miss Distribution Deadline

Delivery data show J&J may miss its target of delivering 20 million doses of vaccine to the US federal government by the end of March. At this point, the company has delivered 20%, or 4 million doses to the government, while 4.6 million vaccines have been distributed to states and federal vaccine programs.

March 25

AstraZeneca Releases Updated Data

After facing scrutiny from the DSMB, the company announces that analyses of more data show the vaccine is 76% effective at preventing symptomatic COVID-19, slightly less than the previously reported 79% efficacy. Some experts find the update reassuring and believe it will likely lead to an authorization by US regulators.

Biden Administration Permits Dialysis Centers to Administer Vaccines

As part of the president’s plan to expand access to COVID-19 vaccines, the Biden administration announces dialysis centers will now be able to administer doses to this population, which is at a high risk of severe illness or death from COVID-19. The move comes after the industry lobbied for the change.

Biden Announces New Vaccine Goal

With 100 million COVID-19 vaccine doses already administered in his first 100 days in office, Biden outlines a new goal of 200 million doses administered within this time frame during his first press conference held since inauguration. The United States is—at this time—on track to meet this goal as 130 million shots have been given.

March 26

J&J Projected to Meet Distribution Goal

The Biden administration announces J&J is set to meet its distribution goal of 20 million does by the month’s end. White House Coronavirus Response Coordinator Jeff Zients notes the company is set to send the government 11 million more doses in the week ahead and plans to significantly increase production by the end of March.

March 29

Some States Open Vaccinations to All Adults

Kansas, Louisiana, North Dakota, Ohio, Oklahoma and Texas announce they are expanding vaccine eligibility to all adults, while Minnesota, Indiana, and South Carolina are expected to follow suit later in the week. Nearly all 50 states have pledged to expand eligibility to all adults by May 1.

Positive Data From Real-World Study on Pfizer, Moderna Vaccines

Real-world data show the mRNA vaccines developed by Pfizer/BioNTech and Moderna are 90% effective in preventing COVID-19 infection. Results also suggest just the first dose of the vaccine was 80% effective at doing so 2 weeks after administration.

March 30

Vaccine Hesitancy Drops

Survey results, reported by Kaiser Health News, show COVID-19 vaccine hesitancy has dropped among all Americans, with the most positive change in the past month seen among Black Americans. Among those polled, the rate of vaccination or intention to get vaccinated grew by 14 percentage points.

March 31

Pfizer/BioNTech Release Adolescent Vaccination Data

As cases of COVID-19 continue to increase week over week, the companies release data from a trial investigating the vaccine’s efficacy among those aged 12 to 15. Results, which have yet to be peer reviewed, show higher antibody responses in this cohort compared with those seen in 16-to-25-year-olds reported in a previous trial.

15 Million J&J Vaccines Spoiled

A batch of J&J COVID-19 vaccines being produced at a Baltimore plant run by Emergent BioSolutions was ruined after workers mixed up the vaccine’s ingredients with another that was being produced at the plant. Production of the J&J vaccine has ceased although the incident will not affect doses currently being circulated throughout the country.

April 1

Vaccine Rollout Marred by Racial Inequities

Data show that months into the nation’s vaccine rollout, those most affected by the pandemic are not being prioritized for vaccination. At the national level, data on the race and ethnicity of those who receive a vaccine are only known for 53% of individuals, marking a large knowledge gap.

Data Show Pfizer/BioNTech Vaccine Effective After 6 Months

Phase 3 trial data indicate the companies’ vaccine is effective after 6 months in individuals who received both doses. No serious safety concerns were reported, and data also show the vaccine is effective against the B.1.351 variant, which first emerged in South Africa.

April 2

CDC Expands Travel Guidelines

The CDC announces that individuals who are fully vaccinated can travel domestically at low risk to themselves, but should still adhere to COVID-19 precautions such as mask wearing and social distancing. Travel is still not recommended due to rising numbers of cases in the United States.

Moderna Vaccine Changes Authorized

The FDA authorizes changes to Moderna’s vaccine that can provide extra doses from each vial, The Associated Press reports. New vials can now contain up to 15 doses each compared with the previous 10 doses. Regulators said that providers can also now safely extract 11 doses from the original vials.

April 5

COVID-19 Vaccine Safe During Pregnancy

A study published in The American Journal of Obstetrics and Gynecology found that COVID-19 vaccines were safe and effective for pregnant and breastfeeding women. Moreover, findings indicated that vaccines may provide protection for babies as well, with antibodies found in umbilical cord blood and breast milk.

Global Coronavirus Coordinator Appointed

Amid growing concerns of vaccine inequity worldwide, the Biden administration appointed Gayle Smith, a former director of the US Agency for International Development, to serve as the new coordinator for its global coronavirus response. Part of Smith’s responsibility will be to mobilize US resources and bolster vaccine production and distribution across the world.

April 6

UK COVID-19 Variant Detected in All 50 States

The COVID-19 variant first identified in the United Kingdom, B.1.1.7, is now present in all 50 states. Indicated by research as more infectious, health experts expressed concerned that the United States may not be able to administer vaccines fast enough to avoid another surge in cases.

April 7

European Medicines Agency Finds Rare Clotting Links to AZ Vaccine

The European Medicines Agency’s safety committee concludes that there is a link between AstraZeneca’s COVID-19 vaccine and “very rare” clotting events. The safety committee further noted that unusual blood clots with low blood platelets should be listed as very rare side effects of the vaccine.

AZ COVID-19 Vaccine Trial in Children Paused in UK

Following blood-clotting issues reported among adults, the University of Oxford paused the most recent arm of AstraZeneca’s COVID-19 vaccine trial among children and teenagers pending more information from the United Kingdom’s pharmaceutical watchdog, the Medicines and Healthcare Products Regulatory Agency.

April 8

UK Variant Now Dominant in United States

The B.1.1.7 COVID-19 variant, first identified in the United Kingdom, is now the dominant strain in the United States. As of April 7, US cases had plateaued at a high level of 61,000 new cases, with no continued significant decreases reported.

April 9

Racial Disparities in COVID-19 Incidence, Mortality in Montana

Authors of a Morbidity and Mortality Weekly Report from the CDC highlight the importance of using state-level surveillance to develop tailored vaccine allocation strategies amid data that show COVID-19 incidence and mortality rates were 2.2 and 3.8 times greater in 2020 for American Indian/Alaska Native individuals compared with White individuals in Montana.

Pfizer, BioNTech Seek EUA Expansion in Adolescents for COVID-19 Vaccine

Following positive trial results of Pfizer/BioNTech’s COVID-19 vaccine among adolescents aged 12 to 15 years, both companies requested that the FDA expand its EUA to include these populations. Pfizer/BioNTech also announce requests for similar authorizations from health agencies worldwide.

April 10

Georgia Becomes Latest State to Pause J&J Vaccine

After 8 people experience adverse reactions to the shot, Georgia joins North Carolina and Colorado in temporarily pausing administration of J&J’s 1-dose vaccine. Eighteen people in North Carolina and 11 in Colorado had previously reported symptoms including dizziness, nausea, and fainting.

Fauci: Booster Shots May Be Needed in 1 Year

Reported by CNBC, Fauci says people may need booster shots for COVID-19 down the road, although current data indicates Pfizer/BioNTech and Moderna’s respective vaccines provide protection for at least 6 months. He notes it is highly likely the vaccines will be effective for a “considerably longer period of time.” Both companies are currently working on developing booster doses.

B.1.1.7. Not Linked With More Severe COVID-19

New evidence indicates B.1.1.7. does not put patients at a greater risk of severe disease, death, or other clinical outcomes in hospitalized patients compared with other variants. Additional data show currently approved vaccines are likely effective against B.1.1.7., the dominant strain in the United States at this point.

April 13

CDC, FDA, Recommend Pausing J&J Vaccine

The agencies came to the decision after 6 cases of cerebral venous sinus thrombosis (CVST), an extremely rare blood clot, were reported throughout the United States and led to 1 death. All cases were among women between the ages of 18 and 48 who developed the disorder within 2 weeks of receiving the dose.

April 14

EC Ends Vaccine Contracts With J&J, AstraZeneca

The European Commission (EC) announces it will not renew COVID-19 vaccine contracts with J&J and AstraZeneca but will continue to focus on vaccines developed by Pfizer and Moderna. The commission also has inquiries into J&J on its delayed vaccine deliveries.

J&J Vaccine Pause Continues

The CDC’s Advisory Committee on Immunization Practices (ACIP) did not vote to continue or lift the pause on J&J’s vaccine, effectively continuing the halt in the United States. The committee cites a lack of evidence and data to make a well-informed decision and is slated to reconvene in 7 to 10 days.

April 16

Study Outlines COVID-19 Blood Clot Risk

Amid the continued pause of J&J's COVID-19 vaccine in the United States, a new study by researchers at Oxford University, which had not yet been peer reviewed, suggests risks of experiencing dangerous blood clots in the brain are 95 times greater among individuals who contract COVID-19 than in those who receive vaccines developed by AstraZeneca, Pfizer, or Moderna.

Factors Contributing to AZ-Vaccine Related Blood Clots

A study in the New England Journal of Medicine unveils the cause behind abnormal, rare clotting events associated with the COVID-19 vaccine manufactured by AstraZeneca and the University of Oxford, finding that antibodies for clot-promoting platelet factor 4 (PF4) on enzyme-linked immunosorbent assay (ELISA) were present in 5 of the 7 patients who developed blood clots.

April 18

Half of All US Adults Have Received 1 COVID-19 Dose

The United States reaches a milestone in combating the COVID-19 pandemic as 50% of all US adults have now received at least 1 vaccine dose. Following news of the global coronavirus death toll topping 3 million worldwide, nearly 130 million people 18 and older have received a vaccine dose nationwide, with the US vaccination rate standing at 61.6 doses per 100 people.

April 19

All Adults Nationwide Eligible for COVID-19 Vaccines

All US adults are now eligible for COVID-19 vaccines, with all 50 states, Washington, DC, and Puerto Rico meeting Biden’s April 19 deadline. Expanded eligibility comes as cases of COVID-19 continue to rise nationwide, with the 7-day average of new cases increasing by 1% from last week—from 66,702 to 67,443—compared with the 7-day average of 53,000 cases per day from 4 weeks ago.

Poll Finds Vaccines May Ease Long-Term COVID-19 Symptoms

A poll of 962 people with long-term COVID-19 symptoms finds that 39% reported mild to full resolution of their lingering symptoms after they were vaccinated. The poll, conducted by a Facebook group called “Survivor Corps,” also says that 46% of respondents’ symptoms remained the same after vaccination and 14% said they felt worse.

April 20

EMA Gives Go-Ahead for J&J to Resume Vaccination

J&J says it would resume rollout of its COVID-19 vaccine among the 27 member states of the European Union in light of a nonbinding recommendation from the European Medicines Agency, which included adding a warning about the possibly associated rare blood clots.

April 21

Fake Pfizer COVID-19 Vaccines in Mexico, Poland

Reports emerge about the distribution of fake Pfizer COVID-19 vaccines in Mexico and Poland; the incidents are attributed to criminal activity. The fraudulent shots reportedly went for $1000 each in Mexico and were found in beer coolers, had fake labels and wrong expiration dates, and were administered to close to 80 patients, with none harmed.

More J&J Vaccines May Have Been Contaminated

Following reports of 15 million J&J vaccine doses spoiled at a Baltimore plant, federal regulators have now found more flaws at the facility. No doses made at the plant have gone out to the public and all J&J doses distributed in the United States were manufactured overseas.


April 23

ACIP Votes to Lift Pause on J&J COVID-19 Vaccine

In its second meeting on the matter, members of the CDC’s Advisory Committee on Immunization Practices (ACIP) voted to reinstate the original emergency use authorization of J&J’s COVID-19 vaccine in the United States following a pause in administration implemented on April 13.

States See Drops in Demand for COVID-19 Vaccines

With supply of COVID-19 vaccines outpacing demand in states such as Louisiana, Kansas, and Mississippi, state officials are turning down shipments from the federal government due to low interest in the shots. The low demand puts the United States in a tricky position as it now has tens of thousands of unused COVID-19 vaccine doses in store while other countries like India and Brazil face dire medical emergencies.

April 26

US Pledges Medical Aid to India Amid COVID-19 Spikes

Amid marked spikes in cases of COVID-19 reported in India, the United States pledged to provide more medical aid to the country, which will include raw materials for vaccine production, test kits, ventilators, and personal protective equipment.


US to Share 60M AZ COVID-19 Vaccine Doses With Other Countries

The White House announced that the United States will distribute 60 million doses of the AstraZeneca COVID-19 vaccine to other countries over the next several months. White House officials did not specify which countries would receive the added shipments of the vaccine, which has been shown to be 76% effective at preventing symptomatic COVID-19.

April 27

CDC Eases Mask Restrictions for Fully Vaccinated Individuals

The CDC issues updated mask guidelines for vaccinated and unvaccinated individuals, recommending that fully vaccinated Americans can go outside without masks when walking, jogging, or biking or dining with friends at outdoor restaurants. Masking is still recommended in crowded outdoor areas such as stadiums where distancing is not possible. Indoors, masking is still recommended for both vaccinated and unvaccinated individuals.


April 29

Half of US States Report Drops in COVID-19 Cases

In the last 2 weeks, COVID-19 cases have significantly declined in more than half of US states. The drop comes as federal health officials suggest the virus’ trajectory is improving in the country, although uneven distribution of vaccinations remains a challenge in persuading some Americans to get vaccinated.


April 30

Some Adverse Reactions to J&J Vaccine Related to Anxiety

A CDC report indicates that dozens of reported physical adverse reactions to the J&J COVID-19 vaccine may be caused by anxiety. As the vaccine is a 1-shot dose, it may be preferred to other vaccines among people who have needle aversion, says the CDC, which would make it more likely for these populations to have anxiety-related incidents after vaccination, such as sweating and fainting.


May 3

CVS, Walgreens Wasted More Vaccine Doses Than Most States Combined

Walgreens and CVS were found to be responsible for a majority of wasted COVID-19 vaccine doses in the United States. Of the 182,874 wasted doses recorded by the CDC as of late March, CVS was responsible for nearly half and Walgreens for 21%, amounting to approximately 128,500 wasted shots.

More Than 1 in 5 New COVID-19 Cases Involve Children

The American Academy of Pediatrics announces data findings indicating that children represent 22.4% of new COVID-19 cases nationwide, amounting to 71,649 of 319,601 cases. Experts associated findings with the growing vaccination rates in older adults and populations aged 18 to 24 years, who are the age group with the highest case rates in the United States.


May 4

FDA Preparing to Authorize Pfizer Vaccine in Adolescents

The FDA is reportedly preparing to authorize the Pfizer/BioNTech COVID-19 vaccine in adolescents aged 12 to 15 years following positive trial results in these populations. If granted, the CDC’s advisory panel will likely meet the following day to review clinical trial data and provide recommendations on the vaccine’s use in adolescents.


White House Releases Updated Vaccination Targets

Biden announces a new goal of having 70%, or 160 million, of American adults with at least 1 dose of a COVID-19 vaccine by July 4. At the heart of this push is increasing access via the potential approval of vaccine administration by the FDA among adolescents aged 12 to 15 years.


May 5

Vaccine Patents Protections Temporarily Waived

The United States agreed to back a proposal that temporarily waives intellectual property rights for COVID-19 vaccines to help increase the global supply. With a waiver in place, countries that permit compulsory licensing can more easily allow a manufacturer to export vaccines.

Studies Indicate HIV Does Not Impact Vaccine’s Efficacy

Results of 2 studies on immune responses to the Oxford/AstraZeneca vaccine among individuals with HIV show the vaccine produced similar responses regardless of HIV status. Those with HIV also did not experience more adverse events from the vaccine.


May 6

Teenagers Respond Well to COVID-19 Vaccines

New data showing COVID-19 vaccines’ efficacy in teenagers could help boost momentum in the United States’ lagging vaccination effort, with Moderna’s vaccine appearing to be 96% effective in adolescents aged 12 to 17. Experts hope the encouraging data helps spur young people to get vaccinated and will lead to a more normalized school experience for the 2021-2022 school year.


May 7

Experts Say US Patent Waivers Unlikely to Boost Vaccine Supply Quickly

Experts cautioned that the decision to temporarily waive intellectual property rights for COVID-19 vaccines is unlikely to boost vaccine supply quickly. Many hurdles remain before this stance could be adopted internationally and some doubt the 164 members of the World Trade Organization can reach a consensus.

May 10

EU Announces Contract Extension With Pfizer/BioNTech

Following its decision not to renew a COVID-19 vaccine contract with Johnson & Johnson and AstraZeneca, the European Union announces it will extend its contact with Pfizer/BioNTech. The extension includes the possibility of producing 1.8 billion doses of the companies’ vaccine through 2023 and is guaranteed to result in 900 million doses.

Pfizer/BioNTech Vaccine Approved for Adolescents

The FDA announces it will expand its EUA for the Pfizer/BioNTech vaccine to include adolescents aged 12 through 15. The EUA was initially issued in December 2020 and included individuals aged 16 and older. Acting FDA Commissioner Janet Woodcock, MD, notes the expansion is a significant step forward in the nation’s battle against the pandemic.

May 11

States With Highest, Lowest Vaccination Rates

Data show vaccination rates may differ significantly across the country depending on the region. At this point, every state in the Northeast had given at least 1 dose of a COVID-19 vaccine to at least 60% of its adult residents. Vermont has the highest vaccination rate at 74.5% while Mississippi had the lowest rate with just 41.5% of its population receiving at least 1 dose.

May 12

Vaccine Disparities Reported in California

Data from a Los Angeles Times analysis reveals Black and Latino Californians are less likely to have received a COVID-19 vaccine. Compared with the majority of White and Asian American/ Pacific Islander Californians, only about one-third of Black and Latino individuals in the state have received at least 1 dose of a vaccine.

Nursing Homes Must Report Vaccination Data

New CMS guidelines require long-term care facilities to report residents’ and staffs’ COVID-19 vaccinations each week to the CDC’s National Healthcare Safety network. Officials will use the information to direct more resources to locations in need. The data will be made publicly available on CMS’s COVID-19 Nursing Home Data website.

May 16

Fauci: Vaccine Efficacy Better Than Anticipated in Real-World Setting

Speaking at the American Thoracic Society’s 2021 virtual conference, Fauci says that the real-world evidence of vaccines against SARS-CoV-2, the virus that causes COVID-19, is even better than expected.

May 17

Positive Early Sanofi/GSK Vaccine Results

Results of a phase 2 trial testing Sanofi and GlaxoSmithKline’s (GSK) experimental COVID-19 vaccine indicated participants of all ages developed strong levels of neutralizing antibodies similar to those found in people who have recovered from the virus. A large international phase 3 trial is slated to being in the coming weeks.

May 18

US to Export Excess Vaccines

Biden announces the United States will ship approximately 80 million excess COVID-19 vaccines abroad. Around 20 million doses of Johnson & Johnson, Pfizer, and Moderna vaccines will be shipped out, in addition to around 60 million AstraZeneca vaccines, which are not yet approved in the United States.

May 20

More J&J Vaccines Contaminated at Baltimore Plant

Up to 100 million more doses of the Johnson & Johnson vaccine could have been contaminated at an Emergent BioSolutions plant in Baltimore, Maryland. The vaccines were held up and not distributed, as it was revealed in a House subcommittee testimony the plant housed unsanitary conditions including mold and peeling paint.

May 21

Covax Faces Supply Shortages

The WHO’s Covax vaccine program, aimed at delivering COVID-19 vaccines to the world’s poorest countries, may be unable to meet its goal of supplying 20% of the populations from the world’s 92 poorest countries with free vaccine doses by year-end. Despite deals with several companies, the program’s main supplier in India is unable to export doses due to restrictions put in place by the country’s government and the latest COVID-19 surge.

May 24

Heart Problem Investigated in Vaccinated Teens

The CDC is investigating rare cases of possible myocarditis reported in teenagers and young adults after they received a COVID-19 vaccination. It is unknown if the vaccine causes the condition, and it may be unrelated to the vaccination. Several dozen cases have been reported at this time.

May 25

Potential New Moderna Vaccine Indication

In June, Moderna plans to submit data to persuade the FDA to expand its EUA for the vaccine to include adolescents aged 12 to 17. The new data is based on results from a study of over 3700 participants and efficacy was shown to be 100%, following no reports of symptomatic COVID-19 in the two-thirds of participants who received both doses.

May 26

COVID-19 Infection After Vaccination Is Extremely Rare

New CDC data show the risk of COVID-19 infection among fully vaccinated individuals is 0.01%. The news comes on the heels of the announcement the United States has fully vaccinated more than half of its adult population. Breakthrough infections can still occur in fully vaccinated individuals, as vaccines are not 100% effective.

European Union Seeks Fine for AstraZeneca

Citing a breach of contract, the European Union is seeking a significant fine for the manufacturer. AstraZeneca had previously said it would aim to provide 100 million doses by the end of June, falling short of the 300 million number specified in the contract. A verdict is expected in June.

May 27

Production of Sanofi/GSK Vaccine to Begin

Production of the companies’ COVID-19 vaccine is slated to begin within weeks, as the candidate’s efficacy will be assessed in a trial of over 35,000 adult volunteers in the United States, Asia, Africa and Latin America. Should the trial yield positive results, regulators could approve the vaccine for use in the last 3 months of 2021.

June 1

Employers Can Require COVID-19 Vaccine

Updated guidance from the Equal Employment Opportunity Commission permits employers to mandate the COVID-19 vaccine among their workforce. Employers can also provide incentives, like cash, to workers to get vaccinated. However, employers must still provide accommodations to workers exempt from mandatory immunization under the Americans with Disabilities Act.

June 2

NIAID Study Investigates Vaccines

A new study conducted by NIAID will focus on prolonging immunity and increasing protection from COVID-19 among participants. The study will also seek to optimize vaccine combination treatments if results show booster shots are warranted.

June 3

Initiative Announced to Boost Vaccine Rates

The Biden administration announces a National Month of Action for June with the goal of immunizing at least 70% of Americans with 1 vaccine dose by July 4. Free childcare will be offered to those getting vaccinated while pharmacy chains will extend hours of operation to accommodate more appointments.

US to Donate 75% of Unused Vaccines to Covax

As global COVID-19 vaccine inequities continue to mount, the United States will donate the majority of its unused vaccines to nations in the WHO's Covax program, the Associated Press reports. In making the announcement, Biden noted 25% of the nation's supply will be kept in reserve for emergencies and for the United States to share with allies.

June 10

US to Distribute Pfizer Vaccines

Biden is set to announce his administration will purchase 500 million doses of Pfizer’s COVID-19 vaccine to be donated to the rest of the world, The Washington Post reports. The first 200 million will be distributed via COVAX in 2021 and the rest will be shared in the first half of 2022. The vaccines will be targeted at low- and middle-income countries, while Pfizer is selling the shots to the United States at a low “not-for-profit” price.

June 11

J&J Expiration Date Extended

US regulators extended the expiration date for the Johnson & Johnson (J&J) COVID-19 vaccine by 6 weeks, preventing millions of already-manufactured doses from being wasted, according to The Associated Press. Specifically, the FDA review concluded the doses will remain safe and effective for at least 4.5 months compared with the vaccine’s original 3-month shelf life when stored at normal refrigeration levels. The news comes as the United States temporarily suspended J&J vaccine shipments as states face a surplus of expiring doses, The Wall Street Journal reports. However, the pause is expected to be temporary.

June 14

Novavax Releases Phase 3 Data

Data from a phase 3 trial testing Novavax’s COVID-19 vaccine in the United States and Mexico show that the candidate has 90.4% overall efficacy, CNN reports. The study consisted of 29,960 adults across 113 sites. Novavax’s vaccine candidate is administered in 2 doses, scheduled 21 days apart. Results also indicate the vaccine is 100% effective against severe disease. According to the company, the candidate was 93.2% effective against variants of concern or interest. Further trial analyses are ongoing, and data will be submitted to peer-reviewed journals for publication.

June 23

Delta Variant Concerns Mount


In a White House briefing yesterday, Anthony Fauci, MD, underscored growing concern over the COVID-19 delta variant, according to Forbes, which has grown in prevalence from 9.9% of new cases just 2 weeks ago to 20% this week in the United States. The expanding threat from delta, which Fauci now calls “the greatest threat in the US in our attempt to eliminate COVID-19,” also now accounts for more than 90% of new COVID-19 cases in the United Kingdom. This news comes as the White House announced that President Biden’s goal of 70% of adults having at least 1 COVID-19 vaccine dose by July 4 will not be met.

June 25

COVID-19 Deaths Most Common in Unvaccinated

Almost all COVID-19 deaths recorded in the United States are among those who are not vaccinated, according to The Associated Press. The latest analysis illustrates the efficacy of the COVID-19 vaccines and shows that deaths per day, which are below 300, could potentially reach zero if all eligible individuals receive a vaccine. In addition, “breakthrough” infections among those fully vaccinated are rare—accounting for less than 1200 of over 853,000 hospitalizations, or about 0.1%. The analysis used available government data from May of 2021.

June 30

Vaccinations Lag Among Medicaid Beneficiaries

Data indicate Medicaid enrollees are getting vaccinated for COVID-19 at lower rates than the general population, Roll Call reports. Despite the steady supply of vaccines in the country and expanded eligibility, in Ohio, just 22% of beneficiaries were vaccinated in May compared with 45% of all Ohioans. Low uptake among this population has experts worried, as poorer individuals tend to face worse health outcomes, including shorter life expectancies. Lack of access to transportation and childcare or less flexible work schedules could account for the low uptake. Polls also indicate higher levels of vaccine hesitancy among lower-income individuals.

To see the COVID-19 vaccine developments for the 2nd half of 2021, click here.

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