Expert Commentary

Effectiveness of paid sick days at reducing influenza transmission at work

2013 study by the University of Pittsburgh published in the American Journal of Public Health on the impact of paid sick days on influenza transmission.

Sick man at work (iStock)
(iStock)

Employees come to the workplace sick for many reasons. Some feel guilty about missing work or fear that tasks won’t be done well in their absence. Others are fearful about their job security or don’t have the right to paid sick time — and only 61% do, according to the Bureau of Labor Statistics. Whatever the reason, employees who work despite aches and sneezes aren’t doing their companies any favors: According to a 2007 study by researchers from the Center for Disease Control and Prevention, the flu alone imposes direct medical costs of $10.4 billion a year in the United States.

Another cost imposed on businesses by workers who show up sick is the potential of their infecting others. A 2010 study in the journal Vaccine indicated that 28% of employees who receive paid sick days still work when they’re ill; for those without paid sick days, the rate jumps to 48% — nearly half. A 2013 study by researchers at the University of Pittsburgh refers to this as “presenteeism” — the act of working even while sick — and indicates that it can be the cause of many workplace outbreaks.

The study, “Policies to Reduce Influenza in the Workplace: Impact Assessments Using an Agent-Based Model,” published in the American Journal of Public Health, examined the impact of universal paid sick days on influenza incidence. In an “agent-based” model, “each individual in a population is represented along with the individual’s social contact networks in households, schools, workplaces, and neighborhoods.” In this way transmission patterns and the burdens they impose can be better understood. In the study the population of Allegheny County, Pennsylvania, was simulated, with nearly 1.25 million individuals living in and around the city of Pittsburgh.

Using the model, the impacts of two policy changes were explored: First, the availability of paid sick days for all individuals in the area studied. Second was “flu days” — paid sick days specifically available for those with influenza.

The study’s findings include:

  • In the model, workplace transmission accounts for 11.54% of all flu infections. “On average, there were 66,444 infections overall owing to workplace transmission, including 47,768 infections owing to ‘presenteeism’ among 575,866 employees in Allegheny County.”
  • With universal access to paid sick days, 72% of employees who were ill stayed home for 1.7 days on average. This cut workplace infections by as much as 5.86%.
  • Because larger firms are more likely to offer sick days, smaller firms benefited more from the policy: “Workplaces with 2 to 49 employees had a 7.24% decrease in infections, workplaces with 50 to 99 employees had a 6.80% decrease, workplaces with 100 to 499 employees had a 5.18% decrease, and workplaces with 500 or more employees had a 3.34% decrease in infections.”
  • The “flu day” policy was even more effective: If one flu day was offered, workplace infections fell by an average of 25.33%; if two flu days were offered, infections dropped by 39.22%.
  • Benefits from “flu days” were substantial in all business sizes: “Workplaces with 2 to 49 employees had a 24.66% decrease [in infections], 50 to 99 employee workplaces had a 24.93% decrease, 100 to 499 employee workplaces had a 25.76% decrease, and workplaces with 500 or more employees had a 26.42% decrease in infections owing to workplace transmission from a two-flu-day policy.” For a two-flu-day policy, the decreases in infection rates ranged from 38.38% to 40.77%.

“Multiple factors — including cognitive factors such as guilt associated with missing work and concern about work not getting done as well as social determinants such as job security and access to [paid sick days] — affect employees’ decision to stay home from work when experiencing influenza-like illness symptoms,” the authors say. Getting sick employees to stay home is central to reducing transmission rates and both paid sick days and flu days were found to be effective.

Another factor is flu vaccination, which the Affordable Care Act requires health-insurance plans to provide free of charge. A 2011 metastudy from the University of Minnesota, Johns Hopkins University and the Marshfield Clinic Research Foundation published in The Lancet, “Efficacy and Effectiveness of Influenza Vaccines: A Systematic Review and Meta-Analysis,” indicates that vaccination can prevent the flu up to 67% of the time. Vaccines were most effective with HIV-positive adults ages 18 to 55 (76%), healthy adults ages 18 to 46 (approximately 70%) and healthy children ages 6 to 24 months (66%).

A related 2011 study in the Journal of Virology by researchers at Pennsylvania State University, “Extensive Geographical Mixing of 2009 Human H1N1 Influenza A Virus in a Single University Community,” observed the spread of H1N1 virus within the student body of the University of California, San Diego (UCSD), between October and November 2009. It found that there were between 24 and 33 separate introductions of different strains of the H1N1 virus in just one month, and seven clusters of affected students. Three comprised two separate H1N1 sequences, two others contained three sequences, one cluster comprised four sequences, and the seventh had no less than 14 distinct sequences of the virus.

Keywords: consumer affairs, Affordable Care Act

About The Author