2009 H1N1 flu strain will be in next season flu vaccine

WASHINGTON —The 2009 H1N1 flu virus, which has been circulating since last spring, sickened millions and killed at least 15,000 people worldwide, will be included in the United States’ next seasonal flu vaccine when it becomes available in the fall, government health experts decided Feb. 22.

Every February, the Vaccines and Related Biological Products Advisory Committee advises the Food and Drug Administration on which flu strains to include in the next flu shot or spray.

The committee is following the recommendations of the World Health Organization, Dr. Jerry Weir, the FDA's director of the Division of Viral Products, told CNN.

"This is the same process we go through every year," Weir said. The selection is made early in the year to give flu manufacturers enough time to make enough vaccine by September or October, when health officials recommend people get vaccinated. Pharmaceutical companies need so much lead time because it's takes a long time to grow vaccines in eggs, currently the only licensed method for making flu vaccines.

"The new H1N1 strain didn't exist last February," said Weir, which is why health officials couldn't consider it for the flu vaccine for the current flu season. Once it was determined that this new type of H1N1 flu strain was circulating around the country and the world, flu manufacturers were asked to develop an additional flu vaccine to fight this virus.

The most recent estimates from the Centers for Disease Control and Prevention suggest that 41 million to 84 million people in the Unites States have been infected with 2009 H1N1 since April. The CDC also estimates that 183,000 to 378,000 people were hospitalized and between 8,330 and 17,160 people died from this flu since it emerged.

The agency says its estimate vary widely because not everyone who gets sick goes to the doctor, and not everyone who is hospitalized was tested for this flu and because health officials believe hospitalizations and deaths are under-reported.

The following three virus strains will be included in the 2010-11 seasonal flu shot. A California virus is the pandemic H1N1 virus that caused so much illness in the past 10 months. A Perth virus is an H3N2 virus?. A B Brisbane virus will be included as well.

Weir says now that the three specific strains have been selected, manufacturers can now begin producing the new batch of seasonal flu vaccine.

For those concerned about getting the flu now, the CDC continues to recommend getting the separate H1N1 vaccine, which is widely available.