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2009 H1N1 Flu Vaccine Facts

A Pregnant women

The Centers for Disease Control and Prevention (CDC) and the National Institute of Allergy and Infectious Diseases (NIAID) offer these flu facts to help the American people understand the safety and effectiveness of the H1N1 flu vaccine.

1 The 2009 H1N1 flu vaccine is safe and well tested.

Clinical trials conducted by the National Institutes of Health and the vaccine manufacturers have shown that the new H1N1 vaccine is both safe and effective. The FDA has licensed it. There have been no safety shortcuts.

It is produced exactly the same way the seasonal flu vaccine is produced every year. It is simply a new virus strain. In fact, had H1N1 struck this country earlier than this spring, the H1N1 strain probably would have been included as part of this year's seasonal flu shot.

Millions of Americans get the seasonal flu vaccine each year without any problems. Still, since some Americans have concerns about "new" vaccines, the NIH and the vaccine manufacturers have conducted more thorough tests on the H1N1 vaccine than they do on other flu vaccines. There have been no red flags from these clinical trials.

The risk of the flu, especially for pregnant women, children, and people with underlying health conditions, is higher than any risk that might come from the H1N1 vaccine.

2 Pregnant women should definitely get the 2009 H1N1 flu vaccine.

Changes to a pregnant woman's immune system can make her more sensitive to the flu and result in serious complications if she is infected with H1N1. If you are pregnant, you should get vaccinated against H1N1 as soon as possible. Your vaccination can potentially protect your unborn child from infection.

3 You need only one dose of the H1N1 vaccine.

Good news from our clinical trials being run by the National Institutes of Health and the flu vaccine manufacturers: The H1N1 vaccine is a really good match with the H1N1 virus currently circulating across the country. Healthy adults and children 10 and older will need only one dose of vaccine.

It's also fine to get the seasonal flu shot and the H1N1 shot at the same time. But if you get the nasal spray form of the vaccine, you need to wait three to four weeks before getting another nasal spray vaccine.

4 Flu shots are vaccines from dead or inactivated forms of the flu virus.

Both the seasonal and 2009 H1N1 flu shots are vaccines that contain killed/inactivated influenza virus. The nasal spray H1N1 vaccine contains a live, but weakened, form of the virus that does not cause flu illness.

5 Healthy people are in danger from the new 2009 H1N1 virus, and they should get vaccinated.

Both healthy people and people with underlying health conditions, such as asthma and diabetes and other chronic diseases, are at risk from the 2009 H1N1 flu. In CDC studies, about 70 percent of people who have been hospitalized with this 2009 H1N1 virus have had one or more medical conditions that place them at "high risk" of serious seasonal flu-related complications. Thirty percent of those hospitalized were previously healthy.

The 2009 H1N1 flu has especially affected young people ages 5 to 24. A recent study in the New England Journal of Medicine of 272 hospitalized H1N1 patients showed that 60 percent of the children who were hospitalized had an underlying condition. The remaining 40 percent had no underlying condition.

Read More "Avoiding the Flu" Articles

Avoiding the Flu / 2009 H1N1 Flu Vaccine Facts / What You Can Do to Stop the Flu

Fall 2009 Issue: Volume 4 Number 4 Page 6