The Centers for Disease Control and Prevention offers advice on its Web site, www.cdc.gov, for people concerned about the swine flu and how to take care of themselves and others if they become sick. Health officials at the CDC refer to the new flu as 2009 H1N1.

It's thought to spread in the same way that seasonal flu spreads. The main way that flu viruses are thought to spread is from person to person through coughs and sneezes from people with the flu. Sometimes people become infected after touching some object or surface that has the flu virus on it, and then touching their mouth or nose.

• Symptoms can include fever, cough, sore throat, body aches, headache, chills and fatigue. Some people also have reported diarrhea and vomiting.

• Severity can vary from mild to severe, can progress to pneumonia, respiratory failure and even death. Some people might be more likely to develop a severe illness, such as those with chronic medical conditions. About 70 percent of people who have been hospitalized with this 2009 H1N1 virus are those also at risk of serious complication from the seasonal flu. This includes pregnancy, diabetes, heart disease, asthma and kidney disease.

• One new aspect of this flu is that it seems that adults over 64 do not have increased risk of complications. It may be that many older adults have antibodies to this virus.

• The CDC's analysis of data so far concludes that the 2009 H1N1 flu has caused illness to a greater extent in people younger than 25 than older people. By September, there have been few cases and few deaths reported in people older than 64 -- not usually the case with seasonal flu. The other medical conditions that make a person at high risk of complications remain high-risk with the 2009 H1N1. These underlying conditions include asthma, diabetes, suppressed immune systems, heart disease, kidney disease, neurocognitive and neuromuscular disorders and pregnancy.

• With both seasonal and 2009 H1N1 flu, people may be able to infect others from one day before getting sick to five to seven days after. It can be a longer period, especially with children and people with weakened immune systems.

• Check with your health care provider about any special care that might be needed if you are sick and you are pregnant or have a health condition like diabetes, heart disease, asthma or emphysema.

• Check with your health care provider about whether you should take antiviral medications.

• CDC recommends that people with influenza-like illness remain at home until at least 24 hours after they are free of fever (100 degrees or highter) or free of signs of a fever without the use of fever-reducing medications. Those guidelines may be more stringent in health care settings and places where high numbers of high-risk people may be exposed. The advice may be revised in the future.

• Get plenty of rest.

• Drink clear fluids like water, broth, sports drinks, and electrolyte beverages for infants to prevent dehydration.

• Cover coughs and sneezes.

• Clean hands with soap and water or an alcohol-based hand rub often and especially after using tissues and after coughing or sneezing into hands.

• Avoid close contact with others -- do not go to work or school while ill.

• Watch for emergency warning signs (see below) that might indicate medical attention is needed.

Emergency medical care is needed when the patient:

• Has difficulty breathing or chest pain.

• Has purple or blue discoloration of lips.

• Is vomiting, unable to keep liquids down.

• Has signs of dehydration, like dizziness when standing, absence of urination, or, in infants, a lack of tears when they cry.

• Has seizures.

• Is less responsive or is confused.

• Keep the sick person away from other people as much as possible, away from work and school. Keep sick person away from common areas and, if possible, in a separate room with separate bathroom.

• Remind sick person to cover coughs, and clean their hands with soap and water or an alcohol-based hand rub often, especially after coughing and/or sneezing.

• Have everyone in the household clean their hands often, using soap and water or an alcohol-based hand rub.

• Ask your healthcare provider if household contacts of the sick person -- particularly those contacts who may have chronic health conditions -- should take antiviral medications such as oseltamivir (Tamiflu) or zanamivir (Relenza) to prevent the flu.

• Sick persons should wear a surgical mask -- if one is available and tolerable -- if they need to be in a common area of the house near other persons.

• Keep other people away from the sick person as much as possible, especially people at high risk of complications from the flu.

• Pregnant women should not be caregivers because they are at increased risk of flu-related complications.

• All persons in the household should clean their hands with soap and water or an alcohol-based hand rub frequently.

• If you are in a high risk group for complications, avoid close contact (within 6 feet) with household members who are sick. If close contact with a sick individual is unavoidable, consider wearing a facemask or respirator, if available and tolerable. Infants should not be cared for by sick family members.

• Do not share cloth towels in the household and maintain good ventilation in shared household areas to prevent the spread of the virus.

• Avoid being face-to-face with the sick person.

• When holding small sick children place their chin on your shoulder so that they will not cough in your face.

• Clean your hands with soap and water or use an alcohol-based hand rub after you touch the sick person or handle used tissues or laundry.

• Caregivers might catch flu from the person they are caring for and then spread it before showing symptoms. Therefore, the caregiver should wear a mask when leaving home to keep from spreading flu while in early stages of infection.

• Talk to your health care provider about taking antiviral medication to prevent getting the flu.

• Monitor yourself and household members for flu symptoms and contact a telephone hotline or health care provider if symptoms occur.

Note: An N95 respirator that fits snugly on your face can filter out small particles that can be inhaled around the edges of a facemask, but it is harder to breathe through an N95 mask for long periods of time. More information on facemasks and respirators can be found at www.cdc.gov/swineflu. Facemasks and respirators may be purchased at pharmacies, or building supply or hardware stores.

• Avoid being closer than within six feet of sick person.

• If you must be close to sick person (for example, hold a sick infant), spend the least amount of time possible in close contact and try to wear a facemask like a surgical mask or N95 disposable respirator.

• Wear an N95 respirator if you help a sick person with respiratory treatments using a nebulizer or inhaler, as directed by their doctor. Respiratory treatments should be performed in a separate room away from common areas of the house when at all possible.

• Used facemasks and N95 respirators should be taken off and immediately thrown in the trash.

• Avoid re-using disposable facemasks and N95 respirators if possible. If a reusable fabric facemask is used, it should be laundered with normal laundry detergent and tumble-dried in a hot dryer.

• After removing a facemask or N95 respirator, clean your hands with soap and water or an alcohol-based hand sanitizer.

• Throw away tissues and other disposable items used by the sick person. Wash your hands after touching used tissues and similar waste.

• Keep surfaces (especially bedside tables, bathroom surfaces and children's toys) clean by wiping them down with a household disinfectant according to directions on the product label.

• Linens, eating utensils, and dishes belonging to sick persons do not need to be cleaned separately, but importantly these items should not be shared without washing thoroughly first.

• Wash linens by using household laundry soap and tumble dry on a hot setting. Avoid "hugging" laundry prior to washing it to prevent contaminating yourself. Clean your hands with soap and water or alcohol-based hand rub right after handling dirty laundry.

• Eating utensils should be washed either in a dishwasher or by hand with water and soap.

The Centers for Disease Control and Prevention Hotline (1-800-CDC-INFO) is available in English and Spanish, 24 hours a day, 7 days a week.