H1N1 Influenza (Swine Flu)

	What Is H1N1 Flu?
	Cause
	Symptoms
	When to Call a Doctor
	Exams and Tests
	Treatment
	Prevention
	Latest Information About H1N1 Flu
	Other Places To Get Help
	Related Information
	References
	Credits
	Audio articles:
	English
	Español

H1N1 flu, sometimes called swine flu, is an infection caused by a new kind of influenza virus that spreads from one person to another. In 2009, the U.S. Centers for Disease Control and Prevention reported an outbreak of this new strain of flu in Mexico, the United States, and other countries. The virus that causes this type of flu is the H1N1 virus.

When you have H1N1 flu, you may feel tired and achy and have a sore throat, a fever, and a cough. Most of the time, the illness is not serious. But severe cases can lead to pneumonia, serious lung problems, and death. If you have another health problem, H1N1 flu can make it worse.

H1N1 flu is caused by the H1N1 influenza virus. At first, experts thought that the virus was spread from pigs to people. But they later found that H1N1 flu is caused by a new virus. After a person is infected, he or she may spread the flu to other people by coughing or sneezing.

Drops from a cough or sneeze from an infected person can move through the air. Breathing them in can make you sick. You can also get infected by touching something with the flu virus on it, such as a desk or counter, and then touching your mouth or nose.

You can't get H1N1 flu from eating pork.

The symptoms of H1N1 flu are the same as regular human flu. They can include:

• Fever or shaking chills.
• Cough.
• Sore throat.
• Body aches.
• Headache.
• Extreme tiredness (fatigue).

Some people also have vomiting and diarrhea. Most of the time, the illness is not serious. But in severe cases, H1N1 flu can lead to pneumonia, serious lung problems, and death. If you already have a health problem, H1N1 flu can make it worse.

Some people are more likely to have serious problems from H1N1 flu, including:

• Pregnant women. The developing baby also is at risk for problems if the mother gets H1N1 flu.
• People with long-term (chronic) problems such as asthma or diabetes.
• People with a weak immune system.
• People who have serious heart or kidney disease or some diseases that affect nerves and muscles.
• People younger than 25 years old.

If you are infected with H1N1 flu, you can infect others 1 day before your symptoms start and up to 7 days after you get sick.

For your child

Call 911 or other emergency services if:

• Your child has severe trouble breathing. Signs may include the chest sinking in, using belly muscles to breathe, or nostrils flaring while your child is struggling to breathe.

Call your doctor now or seek immediate medical care if your child:

• Has a fever with a stiff neck or a severe headache.
• Is confused, does not know where he or she is, or is extremely sleepy or hard to wake up.
• Has trouble breathing, breathes very fast, or coughs all the time.
• Has signs of needing more fluids. These signs include sunken eyes with few tears, dry mouth with little or no spit, and little or no urine for 8 or more hours.

For you

Call 911 or other emergency services if:

• You have severe trouble breathing.

Call your doctor now or seek immediate medical care if you:

• Have increased trouble breathing.
• Have a fever with a stiff neck or a severe headache.
• Are sensitive to light or feel very sleepy or confused.

If you think you have the symptoms of H1N1 flu or if you have been around someone with H1N1 flu, call your doctor or go to the Centers for Disease Control and Prevention Web site (www.cdc.gov/H1N1flu) for more information on what to do.

If your doctor thinks you have H1N1 flu, he or she will do a physical exam and ask you questions about your symptoms and past health.

Your doctor may also take a nasal swab to test for the virus. If this test is needed, it is usually done within the first 4 or 5 days of illness.

If you get sick:

• Talk to your doctor. You may need to get tested to be sure you have H1N1 flu.
• Stay home from school or work until you are feeling better and your fever has been gone for at least 24 hours. Try to avoid being around other people. This will reduce the risk of spreading the flu to others.
• If you have to go outside, wear a mask over your nose and mouth if you can.
• Cover your nose and mouth with a tissue when you cough or sneeze. Throw the tissue in the trash after you use it.
• If you don't have a tissue, cover your mouth when you cough or sneeze. Use the bend in your arm, rather than using your hands.
• Wash your hands every time you cough or sneeze.

To treat H1N1 flu, your doctor may prescribe an antiviral medicine such as oseltamivir (Tamiflu) or zanamivir (Relenza). These medicines can help you feel better faster and may prevent other health problems caused by the flu.

The medicines work only if you start to take them within 2 days after your symptoms start.

A vaccine can help prevent you from getting H1N1 flu. People who most need the vaccine are:¹

• Pregnant women.
• People who live with or care for children younger than 6 months of age.
• Health care workers who take care of sick people.
• People ages 6 months to 24 years.
• People 25 to 64 years old who have long-term (chronic) health problems (such as asthma or diabetes) or who have a weak immune system.

Here are some other things you can do to keep from getting sick:

• Avoid close contact with others who are sick.
• Wash your hands often, using soap and water. Alcohol-based hand cleaners also work well.
• Avoid touching your eyes, nose, and mouth. Germs spread this way.
• Try not to touch surfaces that may be contaminated with the virus. Some viruses and bacteria can live for 2 hours or longer on surfaces such as doorknobs, cafeteria tables, and desks.
• Try to stay in good general health. Get plenty of rest, eat healthy foods, and drink lots of fluids.

These organizations are studying and keeping track of H1N1 flu, including what is being done to prevent its spread. Their Web sites have the most up-to-date information about H1N1 flu:

• U.S. Government. You can find information at www.pandemicflu.gov.
• U.S. Centers for Disease Control and Prevention (CDC). You can find information at www.cdc.gov/H1N1flu.
• World Health Organization (WHO). You can find information at www.who.int/csr/disease/swineflu/en.

Organization

Related Information

• Deciding About Getting the H1N1 Influenza (Swine Flu) Vaccine
• Fever, Age 11 and Younger
• Fever, Age 12 and Older
• Influenza
• Respiratory Problems, Age 11 and Younger
• Respiratory Problems, Age 12 and Older

Citations

1. Centers for Disease Control and Prevention (2009). Use of influenza A (H1N1) 2009 monovalent vaccine: Recommendations of the Advisory Committee on Immunization Practices (ACIP), 2009. MMWR, 58(RR-10): 1–8. Also available online: http://www.cdc.gov/mmwr/pdf/rr/rr5810.pdf.