The CDC reminds the public every influenza season that those infected can spread the virus one day before symptoms appear. Yet, even when the first symptoms occur, healthcare workers (HCWs) may continue working with acute respiratory illness.

The continuing problem of presenteeism was documented recently in a study1 of nine Canadian hospitals, where healthcare staff worked an average of two days with upper respiratory symptoms during flu seasons.

The workers were enrolled in active surveillance for acute respiratory illness (ARI) during the 2010-2011 and 2013-2014 flu seasons. Daily illness diaries during ARI episodes were used to compile symptoms and job attendance.

“We found that 50% of participants working in Canadian acute care hospitals reported episodes of ARI during each influenza season, with 95% of those who reported an ARI working one or more days of their illness,” the authors reported.

Healthcare personnel worked for a mean of 1.9 days with symptoms of an ARI and took an average of 0.5 days of sick leave during flu season. Overall, HCWs were more likely to work if symptoms were less severe, particularly on the illness onset date.

“HCWs in our study were more likely to work on the first day of illness, when viral shedding and risk of transmission are higher,” they noted. “HCWs working in high-risk areas were more likely to work during an ARI, emphasizing the need to be concerned about the risk of transmission to vulnerable patients.”

HCWs were significantly less likely to work while ill in facilities that established exclusion policies for symptomatic workers, or that mandated one week furlough for laboratory-confirmed influenza.

“Our data provide an estimate of the impact of such policies: HCWs in acute care settings would miss an average of two additional days of work each influenza season,” they concluded.

Recommendations for employee health professionals included educating workers on viral transmission risks and raising awareness of when they could infect patients or colleagues.

“Although only 3% of days worked while ill in our cohort were because the HCWs could not afford to stay home, 80% of our participants had paid sick leave,” the authors said. “Policies that provide pay for HCW absence during communicable disease illness episodes may help reduce the percentage who work while ill.”

Hospital Employee Health sought additional comment on the findings from principal author Brenda Coleman, PhD, clinical scientist in the infectious disease epidemiology research unit at Mount Sinai Hospital in Toronto.

HEH: At least one ARI episode was reported by 50.4% of participants each study season. Can you comment on the hospital’s flu immunization rate, and whether any of these workers had the flu?

Coleman: More than 70% of participating healthcare workers were vaccinated against influenza, which is higher than the 50-55% coverage rates reported for all staff in the hospitals. Yes, participants did test positive for influenza — these data are currently being analyzed. About 9% tested positive for influenza.

HEH: Do you think the sick policies generally were too lax in the hospitals studied, and that presenteeism is a problem in the facilities?

Coleman: Sick policies need to be clear, and managers and supervisors need to enforce them. However, we understand that more data about the transmission of respiratory viruses are needed to inform good policies.

HEH: Even mildly symptomatic workers could be a threat to immune-compromised patients, but you found that sick workers were caring for these patients.

Coleman: Yes, we enrolled staff working with immune-compromised patients. It was because of the vulnerability of these and other patients, including newborns, that we were interested in answering the question about working while ill. However, we did not have the sample size required to determine whether staff working with immune-compromised individuals were less likely to attend work while ill than other hospital staff.

HEH: Did you attempt to assess any patient illness related to care by symptomatic workers?

Coleman: No, not in this study. However, it is our intent to try to assess this in future research.

HEH: Did you find evidence of policies that discourage sick leave, like requiring vacation days be taken first? Similar policies are thought to incentivize presenteeism in U.S. hospitals.

Coleman: No, we did not measure sick leave policy impact on presenteeism. However, we agree that some policies, like requiring the use of vacation days and caps on the number of sick episodes, can encourage working while ill.

HEH: Can you elaborate on the point of balancing the effect on the hospital of workers missing two days of work vs. the patient safety benefit of sick workers staying home?

Coleman: The intent of the comment about two additional days of missed work was that it would provide the hospital with a number that could be used in its decision-making about what impact a policy change might incur. We do not have the data available to determine what that impact might be on patient health.

HEH: Was fever used as an indicator for taking sick leave in the hospitals, suggesting those with mild respiratory symptoms could work if they did not run a fever?

Coleman: Yes, many hospitals have policies about not attending work while febrile. As you point out, this would make it acceptable to work with mild symptoms. However, we do not yet know how transmission rates are affected by specific symptoms and their severity.

HEH: Can you comment on the finding of more physicians generally working sick than nurses? Is this a matter of work culture, or the possibility that doctors had more autonomy and were not necessarily bound to employee policies?

Coleman: Physicians are expected to follow hospital policies regardless of their working relationship. However, as many of them are self-employed — no sick leave, greater autonomy — and have other staff who are dependent on their individual attendance, it creates a difference between their professional safety culture and that of other hospital workers.

For example, other hospital staff could theoretically be more easily replaced for sick days than physician specialists.


  1. Jiang L, McGeer A, McNeil S, et al. Which healthcare workers work with acute respiratory illness? Evidence from Canadian acute-care hospitals during 4 influenza seasons: 2010-2011 to 2013-2014. Infect Control Hosp Epidemiol 2019;1-8 doi:10.1017/ice.2019.141. [Epub ahead of print.]