Sunday, February 18, 2007

Any Mask In A Viral Storm?

 

# 474

 

The `conventional wisdom' amongst flubies has been that you really need an N95 mask for decent protection against the H5N1 virus.  Surgical masks, which cost 1/10th of what the NIOSH rated N95 masks cost, are viewed with nearly universal disdain.   That view has been largely supported, up till now, by the medical community. 

 

But that may be changing.

 

A recent report by the University of Pittsburgh Medical Center, of a study conducted by researchers in Hong Kong,  has shown that surgical masks provide a surprisingly good barrier to droplet and aerosolized contaminants.  

 

 

CBN Report: Surgical Masks May Provide Significant Aerosol Protection

By Eric Toner, M.D., February 15, 2007

The relative protection afforded by surgical and N-95 masks is an important issue that is prompting much debate in the process of planning for outbreaks of infectious respiratory diseases such as SARS or an influenza pandemic. In an article published recently in the American Journal of Industrial Medicine, Y. Li and colleagues from The Hong Kong Polytechnic University report the results of their study comparing the in vivo protective performance of surgical masks and N95 respirators [1]. The authors found that N95 respirators filtered out 97% of a test aerosol while surgical masks did almost as well, filtering out 95% of the aerosol.

 

 

At nearly a dollar a pop, and usable generally only for a few hours before needing to be discarded, N95 masks will quickly run out during a pandemic.  Surgical masks are generally more comfortable, and can be had for roughly .10 cents each. 

 

The difference between 97% filtration and 95% filtration is small but significant.  Those working in close proximity to infectious patients, in intensive care units, or performing intubations or nebulizations of H5N1 patients, would probably still want the added protection of the N95 masks. 

 

For the average person, however, surgical masks might prove to be an economical, and more importantly, available alternative.

 

The supply of N95 masks is already stretched thin.  If pandemic jitters should increase, or a pandemic were to start, getting them could become difficult or impossible.  Surgical masks may be more readily available.

 

Personally, I have both in my meager stockpile.  I recognized early on that I couldn't afford to buy enough N95 masks to last through a prolonged pandemic, and so I augmented my small supply of the N95's with regular surgical masks.   If I'm providing direct care to a known or suspected pandemic flu patient, I'll use the N95's, as long as they last.  Otherwise, I'll use the surgical masks.

 

Anyone who waits until a pandemic strikes to purchase supplies, be it food, medicine, latex gloves, or masks, is likely to find that difficult.

 

Better to stock up now, while prices are still reasonable and  it is still possible.