WASHINGTON – The Food and Drug Administration approved a vaccine for the prevention of H5N1 avian influenza.

Influenza A (H5N1) Virus Monovalent Vaccine, Adjuvanted, is for use in people 18 years of age and older who are at high risk of exposure to the H5N1 virus. The vaccine will be added to the National Stockpile for distribution by public health officials if needed. It is not intended for commercial use, FDA said. The US Department of Health and Human Services bought the vaccine from ID Biomedical Corporation of Quebec. The company is a subsidiary of GlaxoSmithKline Biologicals.

“This vaccine could be used in the event that the H5N1 avian influenza virus develops the capability to spread efficiently from human to human, resulting in the rapid spread of disease across the globe,” said Karen Midthun, MD, director of the FDA’s Center for Biologics Evaluation and Research. “Vaccines are critical to protecting public health by helping to counter the transmission of influenza disease during a pandemic.”

FDA said most influenza A viruses don't infect people. But the H5N1 virus has made caused illness and death in people outside the United States. The World Health Organization states that 60 percent of those infected with H5N1 virus die. The virus has the potential to become a pandemic because it continues to infect wild birds which has led to occasional outbreaks of H5N1 in poultry populations. Humans have no immunity to the virus.