The flu (influenza virus infection) can be a very serious illness. The flu is not the sniffles, sore throat, or an upset stomach that goes away in a few days, even though some people think it is. Influenza most often causes fever, body aches, tiredness, and a cough that can last for weeks. Up to 1 in 5 Americans gets the flu each year, and over 200,000 are put in the hospital because of it. About 36,000 people each year die from the problems caused by the flu.

In 2009 there is another type of flu -- the swine flu. It causes the same problems, with fever, cough, and the risk of more serious illness. But this type is caused by a different virus, one that the 2009 flu shot does not protect you from. This is why a new vaccine is being made to prevent this new type of flu. So this year, there are 2 flu shots: the usual one and the swine (H1N1) flu shot. People who need flu shots should take both shots this fall.

These flu vaccines are the best way to prevent the flu. Talk to your doctor about whether or not you should get the flu shots.

What about patients who are getting cancer treatment?

People getting cancer treatment often have weak immune systems. For them, the flu can lead to serious, even life-threatening problems. The flu shot is recommended for most people with cancer.

Many people with cancer worry that the flu shot will make them sick or cause a reaction with other medicines they are taking. Talk to your doctor about this -- he or she knows your situation best and can tell you if you should get the shot and when is the best time to get it. Some people do get mild symptoms, such as a low-grade fever or achy muscles, after a flu shot. These symptoms are caused by the immune system's response to the flu shot and should go away in a day or so. The flu shot cannot cause the flu.

The Centers for Disease Control and Prevention (CDC) says that people with a high risk of having serious problems if they get the flu should get the flu shot every year before flu season begins. It is best if they get it as soon as it is available, or before December. (Flu season is usually from November to April and peaks in January and February each year.) People who are at high risk for problems if they get the flu includes anyone with a weak immune system due to cancer treatment with x-rays (radiation) or drugs (chemotherapy). Those who are very sick should talk to their cancer doctor about getting a flu shot before they do it.

The CDC also recommends that anyone that lives with or cares for a person at high risk for flu-related problems get the vaccine, too. This means that if you are in cancer treatment, your family members and children at home should get the flu shot, too.

Remember that if you have an allergy to chicken eggs you should not get the flu shot.

What types of flu vaccines are recommended for people with cancer?

Cancer patients do have to be careful about the type of flu vaccine they get. There are 2 types available:

• live vaccines are made up of weakened live virus and are given as a nasal spray

• inactivated vaccines are made up of killed virus and are given as actual shots or injections, most often in the arm

One more inactivated vaccine: In 2009, there is an extra flu shot, called the swine flu (H1N1) vaccine. Those who make this special vaccine got a later start, so this vaccine may not be ready when the regular flu shots are. So if you get your flu shot in early fall, you may have to go back to the doctor later for this other shot.

Those who get their shots later in the fall will still need to get 2 shots, since the main shot won't have the swine flu type in it. But you can get both shots at the same time.

Like the standard flu shot, the H1N1 vaccine is an inactivated vaccine. It is OK for most people with illnesses like cancer.

People with cancer and their family members should get the inactivated flu shots, NOT the nasal spray.

How do flu shots work?

Both flu vaccines (the flu shots and the nasal-spray flu vaccine) work in the same way. They cause the body to make antibodies that protect it against influenza virus infection. It takes up to 2 weeks after the shot for the body to do this. This is why you should get the flu shots as soon as you can -- in September if possible. That way your body has time to form the protection you need before flu season starts.

Remember, if you have a serious illness like cancer, you should talk to your doctor before getting any flu shots this year.

Additional resources

More information from your American Cancer Society

We have selected some related information that may also be helpful to you. These materials may be ordered from our toll-free number.

• Swine Flu (Novel H1N1 Flu)

• Infections in People With Cancer

• After Diagnosis: A Guide for Patients and Families (also available in Spanish)

• A Message of Hope: Coping With Cancer in Everyday Life (also available in Spanish)

National organizations and Web sites*

Centers for Disease Control and Prevention (CDC)
Toll-free number: 1-800-232-4636
Web site: www.cdc.gov
Has information on influenza and flu vaccines, including side effects and which types can be used for people with serious illness.

*Inclusion on this list does not imply endorsement by the American Cancer Society.

No matter who you are, we can help. Contact us anytime, day or night, for information and support. Call us at 1-800-227-2345 or visit www.cancer.org.

References

Centers for Disease Control and Prevention. Inactivated Influenza Vaccine 2009-10: What You Need to Know. Accessed at www.cdc.gov/vaccines/pubs/vis/downloads/vis-flu.pdf on August 28, 2009.

Centers for Disease Control and Prevention. Key Facts about Seasonal Influenza. Accessed at: www.cdc.gov/flu/keyfacts.htm on August 28, 2009.

Centers for Disease Control and Prevention. Questions and Answers: Novel H1N1 Influenza Vaccine. Accessed at www.cdc.gov/h1n1flu/vaccination/public/vaccination_qa_pub.htm on August 28, 2009.

Centers for Disease Control and Prevention. Seasonal Flu Vaccine. Accessed at www.cdc.gov/flu/about/qa/fluvaccine.htm on August 28, 2009.

Last Medical Review: 09/03/2009
Last Revised: 09/03/2009