• Influenza A (H1N1) 2009 Monovalent Vaccine Live, Intranasal (Medimmune, LLC): intranasal spray; approved for certain individuals 24 months of age through 49 years (see below).
• Influenza A (H1N1) 2009 Monovalent Vaccine (Sanofi Pasteur Inc.): intramuscular injection; approved for individuals 6 months of age and older.
• Influenza A (H1N1) Monovalent Vaccine (Novartis Vaccines and Diagnostics Limited): intramuscular injection; approved for individuals 4 years and over.
• Panvax® H1N1 Vaccine (CSL Limited): injection; approved for individuals >/= 10 years old.

This is an immunization to prevent H1N1 influenza infection. There are actually 2 different kinds of H1N1 influenza immunizations: an inactivated shot and a live, attenuated nasal mist.

H1N1 Influenza, sometimes called the "swine flu," is an unpleasant virus and in some cases can lead to complications, including pneumonia and death. By immunizing yourself against the disease, you are effectively minimizing your risk of getting the virus. By receiving the vaccine, you can also prevent spreading it to others in your environment who may be at greater risk of complications. There is concern that this virus may continue to be a problem during the 2009/10 flu season. (The seasonal flu, which can in large part be prevented by the regular influenza vaccine, kills over 30,000 people every year in this country, so don't forget to protect yourself against this too.) H1N1 influenza is similar to the seasonal flu with symptoms including fever, chills, aches, congestion, cough, sore throat, and possible diarrhea and vomiting. There are medications that may decrease the severity and duration of the H1N1 influenza if you do get it. Check with your physician.

People with certain chronic health conditions, children and young adults, pregnant women, asthmatics, and people with immune impairment are at greater risk. Unlike the seasonal flu, swine flu has not been as big of a problem for healthy adults over 64 years old, many of whom seem to have some immunity to this illness. Spread of the illness can be limited by the usual precautions inluding handwashing, careful hygiene, and staying home for 24 hours after the fever is gone. Of course, with severe illness, medical attention must be sought. The Centers for Disease Control and Prevention website at http://www.cdc.gov/h1n1flu/general_info.htm provides frequent updates on H1N1. Because the virus that causes H1N1 may continue to mutate and because other factors could increase spread of this disease, this information is subject to change.

For children and adults, the vaccine is a shot given in the deltoid muscle of the upper arm. Infants are usually injected in the upper outer thigh. Children 6 months to 9 years of age should receive a second dose about a month after the first dose.

There is also a nasal spray vaccine preparation. This contains a live, but weakened virus (see discussion below).

Severe reactions, including life-threatening allergic reactions or Guillain-Barré syndrome, can occur but are very rare. Milder reactions from the injectable version include soreness, swelling or tenderness at the injection site as well as headache, muscle ache, or malaise. The milder reactions to the nasal version are runny nose, nasal congestion, sore throat, or fever.

Neither the injection nor the nasal spray are recommended for people with egg allergies, allergy to any vaccine component, a history of Guillain-Barré syndrome or other severe reactions to flu vaccines. Safety has not been established, for either the injectable or nasal form, in pregnant women or nursing mothers.

The nasal spray version is not recommended for asthmatics, for children less than 2 years old, for adults >/= 50 years old, for children less than 5 years old with a history of wheezing or for children or teenagers on aspirin therapy. It should not be given to anyone with sensitivity to egg, egg proteins, gelatin, or arginine. It should not be given to anyone who has had a severe reaction, including Guillain-Barré syndrome, to other flu vaccines. Because the nasal spray contains a live virus, there may be safety issues with this vaccine in patients with weakened immune systems and chronic medical conditions.

Check with your doctor to find out what other ingredients may be in the vaccine, its container, or any diluent in case of allergies or other concerns. Immunization is usually postponed for individuals with a moderate or severe acute illness. Remember that this immunization can only protect against the flu strain covered by the vaccine, not against others strains and other respiratory illnesses. While the injectable version can be given to people with weakened immune systems, adequate immune response cannot be guaranteed.

• Pregnancy
• Age less than 25 years
• Weakened immune system and other chronic health conditions
• Anyone with increased risk for regular influenza