Health-Related Absenteeism Another Measure of Influenza's Reach, CDC Report Says

Workplace absenteeism is an important supplementary measure of the flu's impact on adults of working age, according to a recent CDC report, which said the information can inform prevention messaging and pandemic preparedness planning.

Influenza morbidity is often not accurately reflected through current measures including surveillance and laboratory data, the report said, and the CDC’s National Institute for Occupational Safety and Health’s (NIOSH) monitoring of health-related workplace absenteeism can show additional effects. The report was conducted during the 2017 to 2018 high-severity influenza season using NIOSH’s data of the prevalence of health-related workplace absenteeism and from the Current Population Survey (CPS)—a monthly national survey of approximately 60,000 households conducted by the United States Census Bureau for the Bureau of Labor Statistics.

“During an influenza pandemic and during seasonal epidemics, more persons have symptomatic illness without seeking medical care than seek treatment at doctor’s offices, clinics, and hospitals,” the authors explained. “Consequently, surveillance based on mortality, health care encounters, and laboratory data does not reflect the full extent of influenza morbidity. CDC uses a mathematical model to estimate the total number of influenza illnesses in the United States.”

Health-related workplace absenteeism was defined as working less than 35 hours during a certain week due to the worker’s illness, injury, or other medical issue. During the high-severity influenza season, health-related workplace absenteeism among full-time workers was 1.7% in October 2017 and increased significantly beginning in November. The rate of absenteeism peaked in January 2018 at 3.0% and then steadily decreased to a low of 1.4% in July before increasing again in August and September.

The results of this report are consistent with other studies, as it has been previously recognized that health-related workplace absenteeism correlates with influenza-like illness. However, there are demographic characteristics that could impact the data, including vaccination coverage and access to sick leave.

“Surveillance of workplace absenteeism can provide an important supplementary measure of a pandemic’s impact because conventional morbidity and mortality statistics might not fully reflect the disruption caused to the social and economic life of the community,” concluded the report. “Workplace absenteeism is also one component of the World Health Organization’s Pandemic Influenza Severity Assessment impact indicator.”

The report suggests that state and local health authorities consider these results when developing targeted prevention messages and for monitoring long-term trends of influenza.