washingtonpost.com
Questions And Answers About Swine Flu

Monday, April 27, 2009

Q: What is swine flu?

A: It is an influenza virus, like the strains that cause such misery to people during the winter months. Flu viruses also infect many other species of mammals, as well as birds, and this strain causes a respiratory disease in pigs. It is related to human viruses, but influenza tends to stay in its own "host" species.

How does it pass from pigs to people?

The most common method is through farming, with humans handling infected pigs. The flu can then move on to other people through coughing, sneezing, or touching infected people or surfaces and then touching your mouth or nose.

Such infections are rare because swine flu viruses do not easily attach to human cells of the throat and lungs. However, recent studies have shown human infections may be more common than once believed.

Can you catch swine flu by eating pork from an infected animal?

The Mexican government and the World Health Organization have ruled out any risk of infection from eating pork.

What are the symptoms?

The Mexican government reports seeing these symptoms:

-- Sudden fever above 100 degrees Fahrenheit.

-- Dry cough and/or sore throat.

-- Headache.

-- Joint pain.

-- Nasal congestion.

-- General fatigue.

Those sound like seasonal flu symptoms. How is this flu different?

Swine flu may cause more severe vomiting and diarrhea. In rare cases, flu virus attacks the lungs, a complication that can be fatal. This strain also differs because it is so new. As a result, no one has natural immunity to it, unlike with seasonal flu.

The numbers of infected people are rising quickly. Is this a very infectious disease?

The CDC says it does not yet know. Occasionally a swine flu virus in a person mutates in a way that makes it more easily transmitted from person to person.

People are usually contagious for as long as they are symptomatic -- typically four to five days for adults and longer for children.

I got a flu shot last fall. Will that protect me?

CDC officials say they are "very pessimistic." Tests of last fall's seasonal vaccine and the new virus show no cross-reaction, suggesting that people who got the shot have no added protection against this flu strain.

How should I protect myself and my family?

If you have no symptoms, be preventive: Wash your hands often with soap and water. Cover your mouth and nose when you cough and sneeze, and discard used tissues immediately. Avoid close contact with people who are sick.

If you feel sick, stay home from work and school. Go to the hospital if you experience severe symptoms, such as difficulty breathing.

If you know you have been exposed to swine flu, get lots of rest, and talk to your doctor about the antiviral drugs oseltamivir (trade name Tamiflu) or zanamivir (Relenza). These drugs may make the illness milder and work best if started within two days of getting sick.

I see people in Mexico wearing masks. Should I get one?

Mexico's government is recommending surgical masks for its citizens, but the CDC says the general U.S. public does not need them.

What is the difference between an epidemic and a pandemic?

An epidemic is an outbreak of a disease in a community or region. A pandemic is an epidemic that spreads on a global scale. Epidemics and pandemics may involve a new disease or a new form of an old disease. In the case of a pandemic, few people have immunity to the disease, and it can spread easily between people. Officials are calling the current outbreak an epidemic. Find more information on disease outbreaks.

What are the WHO pandemic phases?

The World Health Organization uses a six-phase scale to help inform the public on the seriousness of a threat and guide pandemic preparedness and response plans. The first three phases involve preparedness, while the last three signal a need for response. For more information about each phase, visit WHO's site on pandemic alerts.

This report includes information from staff writer David Brown, the Associated Press, Reuters, the Los Angeles Times, the U.S. Centers for Disease Control and Prevention, the U.S. Department of Health and Human Services, and the World Health Organization

View all comments that have been posted about this article.

© 2009 The Washington Post Company