CDC Issues Interim Guidance for the Use of Facemasks and Respirators in Non-Occupational Settings during an Influenza Pandemic
By Richard Waldhorn, M.D., May 11, 2007
Surgical masks and N 95 respirators have been recommended for use by healthcare workers during an influenza pandemic, but there is not a consensus about their use in community, non-occupational settings.
In the November 2005 HHS Pandemic Influenza Plan, the use of facemasks by well persons in public settings is not recommended, given a lack of evidence that they confer a public health benefit. Instead, the Department of Health and Human Services (HHS) recommended avoiding close contact with ill individuals.1 In 2006, the World Health Organization (WHO) stated that while masks are not expected to have an appreciable effect on reduction of transmission of pandemic influenza, their use by the general public should be permitted, but not required, as use is likely to occur spontaneously.2 In response to requests for more guidance on this issue, the Centers for Disease Control and Prevention (CDC) has now issued new Interim Public Health Guidance for the Use of Facemasks and Respirators in Non-Occupational Community Settings during an Influenza Pandemic.3
There is very little scientific information available about the effectiveness of facemasks or respirators in preventing disease transmission in non-occupational settings, such as mass transit, public gatherings, or households. The CDC’s guidance relies on the judgment of public health experts and extrapolation from information about the value of facemasks in protecting against large droplet transmission and the value of respirators for protecting against aerosolized droplet nuclei transmission in healthcare settings.4
This new CDC guidance, which supersedes information in the HHS Pandemic Influenza Plan, includes the following recommendations:
Rather than relying on protection from masks and respirators, people should avoid close contact with others who are sick with the pandemic flu strain, and they should avoid large gatherings and crowded places whenever possible.
If close contact and crowded conditions cannot be avoided, people should wear facemasks to help protect themselves from other people’s respiratory droplets (coughs and sneezes) and to help protect people around them.
Respirators should be worn in cases where close contact with infected persons is unavoidable. This includes, but is not limited to, those performing home care for a sick family members or friends.1
The CDC guidance concludes that when combined with other infection precautions such as hand washing and social distancing, correct and consistent use of facemasks and respirators could help protect people and reduce viral transmission during a pandemic.
On May 3, in an accompanying press release, Dr. Julie Gerberding, Director of CDC, commented that people may choose to use masks for extra protection even though there is currently no scientific proof of their effectiveness. She also made reference to studies currently underway that are designed to improve our understanding of the level of protection that facemasks and respirators might provide in a community setting during an influenza pandemic.4
The CDC’s interim guidance represents a significant change in recommendations regarding the use of facemasks and respirators in a community setting, but will have to be revised if and when new information becomes available. Questions about the manufacture, supply, distribution, and education for the public about the use of facemasks and respirators remain unresolved, complicating the practical application of these recommendations.
HHS Pandemic Influenza Plan. www.hhs.gov/pandemicflu/plan. Accessed May 10, 2007.
Nonpharmaceutical Interventions for Pandemic Influenza, National and Community Measures. World Health Organization Writing Group. Emerging Infectious Diseases. 12 (1) 88-94, January 2006.
U.S. Centers for Disease Control and Prevention. Interim public health guidance for the use of facemasks and respirators in non-occupational community settings during an influenza pandemic. May 3, 2007. Available at: http://pandemicflu.gov/plan/community/commaskguidance.pdf. Accessed May 4, 2007.
Interim Guidance on Planning for the Use of Surgical Masks and Respirators in Healthcare Settings during an Influenza Pandemic; www.pandemicflu.gov/plan/healthcare/maskguidancehc.html. Accessed May 10, 2007.
CDC issues interim guidance for the use of facemasks and respirators in public settings during an influenza pandemic: facemasks and respirators could provide added value when used in a combination with other preventive measures. CDC Press Release. May 3, 2007. Available at: http://www.cdc.gov/od/oc/media/pressrel/2007/r070503.htm. Accessed May 10, 2007.