Updated May 2, 2009 — How is the "swine flu" transmitted? And how can you prevent the infection? Surprisingly, swine flu prevention, while not 100% guaranteed, is not complicated or difficult.
The swine flu is the common name for a viral infection normally found in pigs. Technically, it is a strain of the H1N1 subtype of type A influenza. (Read more about flu virus classification and naming.) In April 2009, an epidemic in Mexico showed that it had been transmitted to humans, with hundreds of laboratory-confirmed cases. How is the H1N1 flu transmitted?
The current outbreak is contagious. It has jumped the species barrier and now it can spread from person to person. According to the World Health Organization, this spread is "sustained," meaning it has spread more than once or twice past the initial pig-to-human infections. It is not known, however, how easily the virus spreads among humans. It may or may not be very contagious.
Swine flu is thought to spread from person to person in exactly the same way as seasonal ("regular") flu. The primary means of transmission is sick people coughing and sneezing on healthy people. Tiny droplets of saliva and mucus carry the virus through the air and infect new people. Another means of transmission takes place when healthy people touch surfaces contaminated by the virus (after, for example, being coughed on or touched by a sick person), then touch their mouths or mucous membranes.
Frequent hand-washing is the first line of defense against swine flu infection. Hands should be washed with warm soapy water for at least twenty seconds, vigorously rubbing all surfaces including the nails. Antibacterial soap offers no special protection, but alcohol-based hand sanitizer is effective at killing the virus on relatively clean hands. Hands should be washed and/or sanitized after touching surfaces that may have been touched by a sick person and before meals.
An important part of preventing flu-like illness from being transmitted is the behavior of sick people who may have the virus. Coughs should always be covered, preferably not by the hands; sick people should wash and/or sanitize their hands frequently; and people with flu-like symptoms under no circumstances should go to work or school. While co-workers may be inconvenienced if you call in sick, they will be much more inconvenienced if you give them swine flu!
These measures do not promise that you will not be infected, but each step makes transmission less likely.
Face masks and respirators in community settings may help prevent swine flu prevention, according to the CDC, but should be used only as a last resort. They may help when contact with crowds where swine flu is known to be found, or with known swine flu-infected persons, is unavoidable. They should always be combined with other preventive measures like hand washing and avoiding exposure whenever possible. Masks provide the most benefit when they are worn by people who are already sick (to keep from spreading the virus) and by people in close contact with them.