Coronavirus (555) Types of Mask and COVID-19 Protection (6)

5 May, 2020

Dear Joseph and all,

Thank you for sharing the CDC guidance on masks. This differs markedly from WHO guidance. There is also wide variation in national policies on masks.

WHO guidance is based on a rigorous approach prescribed by the WHO guideline development group. I would be very interested to know the differences between the WHO and CDC approaches to guideline development, and why they appear to have come to quite different conclusions.

WHO guidance is available here:

Neither the WHO nor the CDC guidance specifically answer Ruth Davidge's questions [

Best wishes, Neil

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HIFA profile: Neil Pakenham-Walsh is coordinator of the HIFA global health campaign (Healthcare Information For All - ), a global community with 20,000 members in 180 countries, interacting on six global forums in four languages in collaboration with WHO. Twitter: @hifa_org FB: