Questions and Answers About Swine Flu

Monday, May 4, 2009

Andrew Pekosz, associate professor of molecular microbiology and immunology at Johns Hopkins University's Bloomberg School of Public Health in Baltimore, answers questions about swine flu.

QI got a really aggressive respiratory infection in Mexico in January. Can I still be tested to see whether it was swine flu? Would there be any good reason to test?

A There is no need for you to be tested. The test for swine flu requires the live virus to be present in the sample, and even if that is what you were infected with -- which is highly unlikely, given when you were in Mexico -- the test would come back negative, because the virus is no longer in your body.

I am curious how long the virus lives on surfaces. Schools, buses, etc. are being sanitized across the country, but won't the virus simply die after a given period?

The virus survives a few hours outside the body, but the ability of swine flu to survive has not been directly measured. Cleaning surfaces does not hurt but also should not be used as a replacement for good hygiene. The most important means of transmission is through direct contact with an infected individual, so do not change your hygiene habits because you have disinfected your home or office.

After nearly a week, how have your impressions of the swine flu outbreak changed? Are you more or less sanguine than you were at the start?

There is cautious optimism because we haven't seen very large increases in the numbers of infected people or in the severity of the disease. However, this can change quickly, so continued surveillance is essential.

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