Thursday, January 30, 2020

WHO Interim Advice On The Community, Home, Healthcare Use of Masks For nCoV2019s


With reports overnight of the first cases of nCov2019 now showing up in India and the Philippinesand further spread of this respiratory virus expected over the coming days and weeks, the World Health Organization is faced with the unenviable task of having to provide guidance for the use of what are rapidly becoming scarce resources; surgical face masks and N95 respirators.

Credit NIOSH

This is a thorny subject because the wearing of surgical masks during flu season is a cultural norm in much of Asia (see HK CDW: Surgical Masks For Respiratory Protection), and many public health agencies are now urging people to don masks while in public.

Nearly 3 months ago, in The WHO NPI Guidance : Personal Protection, we looked at the evidence for - and against - the use of face masks by the general  public during an epidemic. And here, the WHO divides mask usage into two types:
  • Wearing a surgical mask by a symptomatic patient to protect others.
  • Wearing a surgical mask by someone uninfected to protect the wearer.

We've looked at the conflicting data on the effectiveness of surgical masks many times over the years (see here, here, and here), and there is little consensus on their merit in protecting the wearer. The WHO also weighed in on the use of homemade, cloth, or reusable masks:
Reusable cloth face masks are not recommended. Medical face masks are generally not reusable, and an adequate supply would be essential if the use of face masks was recommended. If worn by a symptomatic case, that person might require multiple masks per day for multiple days of illness.

The WHO sums up their face mask recommendations, reserving public wearing of face masks by asymptomatic persons to high severity pandemics, while supporting the wearing of surgical masks by symptomatic cases in any scenario.

Yesterday, the World Health Organization released interim guidance for the use of face masks in the Community, the home, and in Health Care facilities.  I've reproduced some excerpts from the 2 page PDF file, but you'll want to read it in its entirety.

When you return, I'll have a postscript:


While I'm an advocate of having surgical (and perhaps a few N95) masks in your emergency kit (you do have a kit, don't you?), I see them more for use when treating a sick family member, neighbor, or friend than I do every-day wear during an epidemic (see my blog on `Flu Buddies') .

Three weeks ago, when you could still order N95s on Amazon I wrote:
While I'm hopeful the Wuhan pneumonia outbreak will be contained, or may recede on its own - as a matter of routine personal preparedness - I always keep a box or two of facemasks, some vinyl gloves, extra hand sanitizer, extra soap, some common OTC flu meds, and a month's supply of essential Rx meds in my emergency stash . . . just in case.
Things you may want to consider adding to your first aid supplies now, while they are still easily affordable, and are in ample supply.
A quick check of Amazon today finds very few suppliers offering N95s, and those are at greatly elevated prices. You can still buy disposable surgical masks (again, the prices have gone up), but how long they will remain available is unknown.

The truth is, if this epidemic expands into something significantly larger, there aren't enough surgical masks and N95 respirators to begin to equip all the front-line healthcare workers who will desperately need them (see NIOSH: Options To Maximize The Supply of Respirators During A Pandemic).
Given the meager evidence that the public wearing of masks - particularly without other layered protective measures (i.e. eye protection, gowns, gloves, stringent hand hygiene, etc. ) - would be beneficial, and the inevitable global shortages in masks and N95s that are already evident, it is understandable why the WHO doesn't recommend their general use in public. 
I'll use my small stash of surgical masks and N95s in my role as a `flu buddy' to friends and neighbors, or to wear if I'm infected to protect others.  I might even slip a surgical mask on if I found myself stuck in a large crowd, but I certainly wouldn't expect much from it.
What I have stocked up on, and is still widely available, is hand sanitizer.  And while it may offer very limited protection - I use it generously during every flu season - and will do so if and when nCoV2019 becomes a significant threat.

The truth is, while you can try to run from a rapidly spreading respiratory virus, successfully avoiding it is another matter entirely.