The number of suspected and confirmed cases of swine flu is increasing daily, and the next week or two will likely determine the severity of the outbreak.

One of the most  common questions we are getting is “Do I need a facemask in public?”

Internal Medicine, Current Health Medical Group

The CDC reports 109 cases nationally, and 14 cases in California. CDC

We are at an early stage, and the risk of contracting swine flu is low at the moment, however, the potential for an epidemic of swine flu is high.  During this evolution of the swine flu outbreak, all precautions should be followed including hand washing, hygiene, and facemaks in crowded areas.  Public areas with higher risk include airline, bus, train, and any public commuter transport. When it is absolutely necessary to enter a crowded setting or to have close contact with persons who might be ill, the time spent in that setting should be as short as possible. If used correctly, facemasks and respirators may help reduce the risk of getting influenza, but they should be used along with other preventive measures, such as avoiding close contact and maintaining good hand hygiene.   A respirator that fits snugly on your face can filter out small particles that can be inhaled around the edges of a facemask, but compared with a facemask it is harder to breathe through a respirator for long periods of time.

When crowded settings or close contact with others cannot be avoided, the use of facemasks or respirators in areas where transmission of swine influenza A (H1N1) virus has been confirmed should be considered as follows:

1. Whenever possible, rather than relying on the use of facemasks or respirators, close contact with people who might be ill and being in crowded settings should be avoided.

1. Facemasks should be considered for use by individuals who enter crowded settings, both to protect their nose and mouth from other people’s coughs and to reduce the wearers’ likelihood of coughing on others; the time spent in crowded settings should be as short as possible.

1. Respirators should be considered for use by individuals for whom close contact with an infectious person is unavoidable. This can include selected individuals who must care for a sick person (e.g., family member with a respiratory infection) at home.

These recommendations will be revised as new information about the use of facemasks and respirators in the current setting becomes available.

The term “facemasks” refers to disposable masks cleared by the U.S. Food and Drug Administration (FDA) for use as medical devices. This includes facemasks labeled as surgical, dental, medical procedure, isolation, or laser masks. Such facemasks have several designs. One type is affixed to the head with two ties, conforms to the face with the aid of a flexible adjustment for the nose bridge, and may be flat/pleated or duck-billed in shape. Another type of facemask is pre-molded, adheres to the head with a single elastic band, and has a flexible adjustment for the nose bridge. A third type is flat/pleated and affixes to the head with ear loops. Facemasks cleared by the FDA for use as medical devices have been determined to have specific levels of protection from penetration of blood and body fluids.

“Respirator” refers to an N95 or higher filtering facepiece respirator certified by the U.S. National Institute for Occupational Safety and Health (NIOSH).

Three feet has often been used by infection control professionals to define close contact and is based on studies of respiratory infections; however, for practical purposes, this distance may range up to 6 feet. The World Health Organization uses “approximately 1 meter”; the U.S. Occupational Safety and Health Administration uses “within 6 feet.” For consistency with these estimates, this document defines close contact as a distance of up to 6 feet.

When to wear a facemask is a personal decision, and this information is a general guide and may be over or under protective and cautions depending on the situation presented