Center for Disease Control and Prevention's H1N1 Q&A

Q. What are the plans for developing novel H1N1 vaccine?

A. Vaccines are the most powerful public health tool for control of influenza, and the U.S. government is working closely with manufacturers to take steps in the process to manufacture a novel H1N1 vaccine. Working together with scientists in the public and private sector, CDC has isolated the new H1N1 virus and modified the virus so that it can be used to make hundreds of millions of doses of vaccine. Vaccine manufacturers are now using these materials to begin vaccine production. Making vaccine is a multistep process which takes several months to complete. Candidate vaccines will be tested in clinical trials over the few months.

Q. How many doses of vaccine are required?

A. The U.S. Food and Drug Administration (FDA) has approved the use of one dose of 2009 H1N1 flu vaccine for persons 10 years of age and older. This is slightly different from CDC's recommendations for seasonal influenza vaccination which states that children younger than 9 who are being vaccinated against influenza for the first time need to receive two doses. Infants younger than 6 months of age are too young to get the 2009 H1N1 and seasonal flu vaccines.

Q. What is the recommended interval between the first and second dose for children 9 years of age and under?

A. CDC recommends that the two doses of 2009 H1N1 vaccine be separated by 4 weeks. However, if the second dose is separated from the first dose by at least 21 days, the second dose can be considered valid.

Q. Can people who are allergic to eggs receive the 2009 H1N1 flu vaccine?

People who are allergic to eggs might be at risk for allergic reactions from receiving influenza vaccines, including the 2009 H1N1 vaccine. People who have had any of the following symptoms or experiences should consult with a doctor or other medical professional before considering any influenza vaccination:

• hives or swelling of the lips or tongue
• acute respiratory distress (trouble breathing) after eating eggs
• documented hypersensitivity to eggs, including those who have had asthma related to egg exposure at their workplace or other allergic responses to egg protein

Because children with severe asthma are at high risk of serious complications from influenza, a regimen has been developed for giving influenza vaccine to children with severe asthma and egg hypersensitivity.

Q. Will the seasonal flu vaccine also protect against the novel H1N1 flu?

A. The seasonal flu vaccine is not expected to protect against the novel H1N1 flu.

Q. Can the seasonal vaccine and the novel H1N1 vaccine be given at the same time?

A. It is anticipated that seasonal flu and novel H1N1 vaccines may be administered on the same day. However, we expect the seasonal vaccine to be available earlier than the H1N1 vaccine. The usual seasonal influenza viruses are still expected to cause illness this fall and winter. Individuals are encouraged to get their seasonal flu vaccine as soon as it is available.

Q. Who is recommended as priority groups to receive the novel H1N1 vaccine?

A. CDC's Advisory Committee on Immunization Practices (ACIP) has recommended that certain groups of the population receive the novel H1N1 vaccine when it first becomes available. These key populations include pregnant women, people who live with or care for children younger than 6 months of age, healthcare and emergency medical services personnel, persons between the ages of 6 months and 4 years old, and people ages of 5 through 64 years of age who are at higher risk for novel H1N1 because of chronic health disorders or compromised immune systems.

The committee recognized the need to assess supply and demand issues at the local level. The committee further recommended that once the demand for vaccine for these prioritized groups has been met at the local level, programs and providers should begin vaccinating everyone from ages 25 through 64 years. Current studies indicate the risk for infection among persons age 65 or older is less than the risk for younger age groups. Therefore, as vaccine supply and demand for vaccine among younger age groups is being met, programs and providers should offer vaccination to people over the age of 65.

Q. Where is the vaccine available?

A. Every state is developing a vaccine delivery plan. Vaccine will be available in a combination of settings such as vaccination clinics organized by local health departments, healthcare provider offices, schools, and other private settings, such as pharmacies and work-places.

Q. Are there other ways to prevent the spread of illness?

A. Take everyday actions to stay healthy. Cover your nose and mouth with a tissue when you cough or sneeze. Throw the tissue in the trash after you use it. Wash your hands often with soap and water, especially after you cough or sneeze. Alcohol-based hands cleaners are also effective. Avoid touching your eyes, nose or mouth. Germs spread that way. Stay home if you get sick. CDC recommends that you stay home from work/school & limit contact with others.

Follow public health advice regarding school closures, avoiding crowds and other social distancing measures. These measures will continue to be important after a novel H1N1 vaccine is available because they can prevent the spread of other viruses that cause respiratory infections.

Q. What about the use of antivirals to treat novel H1N1 infection?

A. Antiviral drugs are prescription medicines (pills, liquid or an inhaled powder) that fight against the flu by keeping flu viruses from reproducing in your body. If you get sick, antiviral drugs can make your illness milder and make you feel better faster. They may also prevent serious flu complications. This fall, antivirals may be prioritized for persons with severe illness or those at higher risk for flu complications.

Source: CDC.gov. 8/27/09. Please refer to the CDC website for the most up to date information.