In a political climate where even widely accepted science may be challenged, the Society for Healthcare Epidemiology of America (SHEA) and other proponents of mandatory flu shots for healthcare workers should be wary of refuting a paper1 that recently cited a lack of data to justify such policies.
“Given the assault on science that we are likely to see over the next four years in the U.S., SHEA must lead by ensuring that all of its recommendations are solidly based in evidence and that expectations for compliance with interventions correlate with the strength of the evidence,” notes Michael Edmond, MD, clinical professor of internal medicine and infectious diseases at the University of Iowa in Iowa City. “Just as we must defend vaccines from false claims of adverse effects, we must also truthfully acknowledge their limitations and shape our policy on science not opinion.”
Edmond wrote those comments in a blog post2 challenging SHEA to drop its recommendation for mandatory flu vaccinations, and further elaborated his position in comments to Hospital Infection Control & Prevention.
“We should reserve things like that for interventions that have the best evidence, the highest quality of evidence to support them,” he says. “Flu vaccination is a good idea. Unfortunately, the flu vaccine is not a good vaccine in terms of effectiveness. Right now that is what we have to work with, and I still feel that there is a benefit to healthcare workers, but we don’t have a high enough level of evidence to mandate it and threaten someone’s livelihood.”
As an alternative, flu vaccination should be voluntary, but highly encouraged to get as many healthcare workers immunized as possible.
“But to say that we are going to fire you?” he says. “Over the last 10 years or so there have been years where the vaccine is barely 20% effective — one year it was 10% effective. Are you are going to fire people because they didn’t get a vaccine that is 10% effective? And we can’t even prove if they got it, it would reduce influenza in patients. We would have to have a very tight set of data to take it to that level. I can’t think of another example that is taken to this extreme, without a very high level of evidence to support it.”
While clarifying that she spoke for herself and not for SHEA, one of the authors of the association's flu vaccination position paper reminded HIC that the Canadian paper is a re-analysis of four randomized controlled trials (RCTs) evaluating the effect of staff vaccination on patient outcomes in long-term care settings.
“The Canadian paper does not present new data,” says Hilary M. Babcock, MD, MPH, medical director of the BJC Infection Prevention and Epidemiology Consortium at Barnes-Jewish and St. Louis Children’s Hospitals. “Recommendations supporting mandatory influenza vaccination for healthcare workers are built on more than just those four supportive RCTs.”
Influenza vaccination of staff is an important part of any facility’s comprehensive influenza prevention and management plan, which should also include early identification and isolation of patients as well as comprehensive and common sense sick time policies that direct ill healthcare workers to stay home, she says.
“We all agree that a better influenza vaccine is sorely needed, one with more effective and more durable protection,” Babcock says. "But while we are waiting for a better vaccine, we should use the one we have. Most people agree that high levels of staff influenza vaccination coverage are desirable. The literature clearly shows that a mandate is the most reliable and durable way to reach those levels.”
Babcock also co-authored a blog post3 responding to Edmond, emphasizing key points summarized as follows in support of mandatory flu vaccinations:
- Not all people with flu show classic influenza-like illness (ILI) symptoms. This is often missed in criticisms of vaccine effectiveness. Studies that look just at vaccine effect on ILI will likely miss true influenza outcomes, while also capturing infections due to other viruses not covered by influenza vaccination.
- Since clinical testing is usually prompted by typical ILI symptoms, lab-confirmed influenza in missed cases may not be determined.
- Asymptomatic people with flu can still shed the virus. The role of asymptomatic infection has been noted in numerous studies of households and experimental challenges.
- Healthcare workers come to work sick. Studies consistently note that some 75% of healthcare workers with febrile ILI admit to working while ill, a startling yet unsurprising fact that does not capture those with atypical, mild, or even asymptomatic infection. This is a major infection prevention issue.
- Patients are at higher risk for complications from influenza than the general public. Many patients won’t be adequately protected by receiving the vaccine themselves. Most HCWs are healthy and therefore more likely to have a robust immune response to vaccine than already-ill patients, many of whom are elderly and/or immunosuppressed.
REFERENCES
- De Serres G, Skowronski DM, Ward BJ, et al. (2017) Influenza Vaccination of Healthcare Workers: Critical Analysis of the Evidence for Patient Benefit Underpinning Policies of Enforcement. PLoS ONE 2017; 12(1): doi:10.1371/journal.pone.0163586.
- Edmond, M. It’s time to finally fix this. http://bit.ly/2lCiLgf.
- Babcock H, Talbot T. Reporting bias: Missing the point of HCP influenza vaccine mandates. http://bit.ly/2l88W93.
