Influenza Vaccine Questions & Answers from the Centers for Disease Control and Prevention (CDC)

• Q&A: Flu Vaccine
• Q&A: Thimerosal-Containing Influenza Vaccine
• Q&A: Nasal Spray Flu Vaccine 
• Q&A: Influenza Vaccine Production, Supply & Distribution in the U.S.

2007 - 2008 Influenza Vaccine Strains

Both the inactivated and the live, attenuated influenza vaccine prepared for the 2007--08 season will include:

• A/Solomon Islands/3/2006 (H1N1)-like;
• A/Wisconsin/ 67/2005 (H3N2)-like, and;
• B/Malaysia/2506/2004-like antigens.

These viruses will be used because they are representative of influenza viruses that are anticipated to circulate in the United States during the 2007--08 influenza season and have favorable growth properties in eggs.

The inactivated influenza vaccine (the "flu shot") is FDA-approved for persons aged >6 months, including those with high-risk conditions, whereas the live, attenuated influenza vaccine (the nasal-spray flu vaccine) is FDA-approved for use only among healthy persons aged 2--49 years. All children aged 6 months through 8 years who are receiving flu vaccine for the first time should receive 2 doses of vaccine.  Children 6 months through 8 years who received flu vaccine for the first time during the previous influenza season, and got only one dose, should receive 2 doses this season.  Children who were given influenza baccine during any other prior flu season should receive only one dose, however.