Health Tools

Health Tools help you make wise health decisions or take action to improve your health.

	Decision Points focus on key medical care decisions that are important to many health problems.
	Flu Vaccines: Should I Get a Flu Vaccine?

Cause

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.

Symptoms

The symptoms of H1N1 flu are a lot like the regular seasonal 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 some cases, H1N1 flu can be severe and can lead to pneumonia, serious lung problems, and death.

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) health 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.

Incubation and contagious periods

The time between getting infected with H1N1 virus and feeling sick (called the incubation period) is usually about 2 days but can be from 1 to 7 days.¹ You can infect others starting 1 day before your symptoms start. And you may infect others up to 12 days after you get sick, although most people are infectious for about 6 days.¹