The best way to avoid getting the 2009 H1N1 flu (formerly known as swine flu) is to get vaccinated once the vaccine becomes available in the fall of 2009. The vaccine is especially recommended for the following high-risk groups, in order of CDC-recommended priority:

• Pregnant women

• Those caring for infants younger than six months of age

• Health professionals

• Children 6 months to 18 years, as well as young adults ages 19 to 24

• Adults ages 25 to 64 with chronic health conditions

Once the high-risk groups have been vaccinated, the CDC recommends that all adults ages 25 to 65 be offered the vaccine, followed by adults older than 65. Older adults remain a top priority for the seasonal influenza vaccine, however.

Whether or not you're vaccinated, you can take certain personal steps to protect yourself and your family from getting the virus that causes the flu.

Flu viruses, including H1N1, are spread by germs in saliva and mucus that are released when someone coughs or sneezes. Flu is spread easily from person to person; if you're within three to six feet of a person with the flu when they cough or sneeze, you can breathe in the virus and get sick. Flu symptoms show up one to four days (usually two days) after you breathe in the virus. Adults with the H1N1 flu can spread it from one day before symptoms appear to about one week after. Children can spread the flu even longer after they get sick.

Flu virus can also live for a very short time on things you touch, such as doorknobs, phones, and toys. However, although the CDC currently recommends frequent and thorough hand washing to prevent spreading or contracting the flu, some experts have pointed out that, so far, no study has shown that hand washing prevents flu transmission. Unlike cold viruses, which are known to infect people when someone touches a germy finger to an eye or nose, it's likely that influenza viruses need to get directly into the lungs in order to cause illness. That's easy for the flu virus to do when lots of people are coughing and sneezing.

Good hand washing is still important, though, because cold viruses do definitely get transmitted by germs on doorknobs and other surfaces, and colds can cause many unpleasant symptoms too.

If you suspect you have the flu, it's important to stay home and try not to expose others to coughing and sneezing. Wearing a face mask, whether you're the sick person or a family member, can also be helpful.

Occasionally, some doctors give anti-influenza drugs to family members to reduce the chance of transmission, a practice called prophylaxis. However, since there are concerns about the flu viruses becoming resistant to the drugs, the CDC recommends that antiviral drugs be used for prophylaxis only under special circumstances, such as for people who are immunosuppressed or have chronic pulmonary conditions such as asthma.