Does Wearing a Mask Reduce Flu?

October 8, 2018 11:44 AM

I work at an organization where if you don't get the flu shot you're required to wear a mask all flu season. I've already gotten my flu shot, so no worries there, but I'm curious if there are there any reputable (NEJM, JAMA, The Lancet, CDC, NIH, etc.) sources that suggest that having un-vaccinated people wear a mask during flu season is effective reducing/preventing the transmission of flu?

I've seen some CDC documents that suggest when you have someone that might have the flu they immediately should put on a mask, and any healthcare workers that will be in contact with them wear a mask, but again nothing suggesting that wearing a mask all season is helpful.

posted by gregr to Health & Fitness (9 answers total)

Effectiveness of facemasks to reduce exposure hazards for airborne infections among general populations
However, despite much research effort, the effectiveness of facemasks for preventing the contraction of influenza is still under debate and the results presented are not viewed as conclusive [12,17,18]. For instance, the Centre for Disease Control and Prevention commented that there were only limited data available on the effectiveness of facemasks in preventing transmission of H1N1 (or seasonal influenza), while the UK's National Health Service (NHS) did not recommend the use of facemasks for healthy people in the community as there was ‘no conclusive evidence that facemasks protect healthy people in their day-to-day lives’ [19]. Nevertheless, some recent research results have observed that facemasks significantly reduce the risk of contracting influenza-like illnesses in households [12,20].
posted by Comrade_robot at 11:53 AM on October 8, 2018 [2 favorites]

I would peruse this document, particularly “Part I. Review of Scientific Data...” and the reference list. I quickly searched through the references for “influenza” and “mask” and they reference a body of literature that goes back literally 100 years, so there’s a lot to look at.
posted by MadamM at 2:07 PM on October 8, 2018

Is it possible that this is just a bit of a stick? Wearing a mask is annoying as hell. You don't have to do it if you get the shot. They may not be able to require you to get a shot, but they can make your life annoying if you don't get it?
posted by fiercecupcake at 3:23 PM on October 8, 2018 [3 favorites]

("Stick" as in "stick and carrot," since I realized afterward stick/jab/shot.)
posted by fiercecupcake at 3:23 PM on October 8, 2018

In public-facing positions it's also a signal to folks who are immunocompromised to be cautious around or avoid being helped by that individual, so in that way I suppose it could help to prevent flu.
posted by camyram at 4:51 PM on October 8, 2018 [2 favorites]

Not your question, I know, but wearing a mask when you haven't been vaccinated is also to protect the people you're around when you might be infectious, and not especially symptomatic. You might think it's a mild cold, or a little allergic sniffle, and still be potentially spreading virus.
posted by cameradv at 8:29 PM on October 8, 2018 [3 favorites]

Response by poster: The policy at my work implies that there's solid research indicating wearing a mask is effective if you don't have a flu shot. As far as I can tell, there's no research that says this. So it seems like a punishment to me.

I am curious if there is solid research saying that it is effective and not a punishment.

(I also understand that punishments can be an effective way of increasing vaccination, but I'm curious if there's data indicating that the mask reduces the flu.)
posted by gregr at 7:27 AM on October 9, 2018

A somebody who works in a quasi-related field: from my quick review of the literature, the short summary is that yes, face masks and hand hygiene probably do reduce transmission of influenza. However, most people will not wear face masks consistently (adherence is not great), so studies are conflicting/difficult to interpret.

Certainly there is enough literature that your employer can make a case for, and there is literature that you can point at to make a case against. In this case your employer will likely win the argument. You will have a difficult time finding anything that unequivocally says that masks are ineffective because theoretically they should have some effect.

Also, I do recommend getting a flu shot in any case.
posted by Comrade_robot at 7:43 AM on October 9, 2018

I don't know how it would be effective, since viruses are also spread via things people touch.
posted by KleenexMakesaVeryGoodHat at 10:26 AM on October 9, 2018