Is flu on the rise among workers? Those working in public health track the number of flu-related hospital and doctor visits, but many people suffer symptoms and don’t seek medical treatment. So, how do we know how many people are sick with the flu during a flu pandemic or a seasonal epidemic?

Each year, the Centers for Disease Control and Prevention (CDC) uses a mathematical model to estimate the total number of flu illnesses in the United States, but this is not done until the end of the flu season. Conventional flu surveillance relies on healthcare data such as lab test results, hospitalizations and doctor’s office visits. Tracking absenteeism trends in workplaces during the flu season is an important supplement to conventional flu surveillance because, often, those who are sick will stay home from work, but they may not see a doctor.

The National Institute for Occupational Safety and Health (NIOSH) is monitoring health-related workplace absenteeism among full-time workers in the U.S. using data received monthly from the Current Population Survey. The results are made available online using a Tableau dashboard. These data are useful for assessing the occurrence of illnesses like the flu since the amount of health-related absences is strongly related to the amount of flu-like illness occurring at about the same time (1). Therefore, workplace absenteeism provides additional information to measure the overall impact of seasonal flu epidemics or pandemics.

Results from the first year of surveillance analyses are available in a new report published in MMWR, “Health-Related Workplace Absenteeism Among Full-Time Workers — United States, 2017–2018 Influenza Season”.

The first year of data found that during the high-severity influenza season of 2017-2018:

  • Absenteeism:
    • increased sharply in November
    • peaked in January
    • at its peak, was significantly higher than the average during the previous five seasons
  • Workers most affected included:
    • men
    • workers aged 45–64 years
    • workers living in Department of Health and Human Services Region 6 (Arkansas, Louisiana, New Mexico, Oklahoma, and Texas) and Region 9 (Arizona, California, Hawaii, and Nevada )
  • Jobs most affected included:
    • management, business, and financial
    • installation, maintenance, and repair
    • production-related jobs

The findings are consistent with other surveillance from the 2017-2018 flu season. Learn more about last year’s workplace absence trends, and view the most recent trends.

We would like to hear from you. Does your workplace have a plan for protecting workers while maintaining operations during an influenza pandemic? Click here to visit the NIOSH Science Blog post and leave a comment.


  1. Groenewold MR, Konicki DL, Luckhaupt SE, Gomaa A, Koonin LM. Exploring national surveillance for health-related workplace absenteeism: Lessons learned from the 2009 influenza A pandemic. Disaster Med Public 2013;7:160–6.