what is h1n1 vaccine

The H1N1 vaccine is a vaccine used to prevent infection caused by the influenza A (H1N1) 2009 virus. It works by causing the body to produce its own protection (antibodies) against the disease. The vaccine was first made available in early October 2009, and both the injected vaccine (flu shot) and nasal spray forms of the vaccine were produced and licensed by the Food and Drug Administration. The vaccine was recommended for people at highest risk for complications from the virus, or those caring for high-risk individuals who cannot receive vaccination, to receive the vaccine first. Children younger than 10 years old were recommended to receive two doses of the vaccine, as studies showed that after one dose, infants and young children do not make as many antibodies compared with older children and adults who get one dose. The vaccine underwent the usual testing and lot release procedures that are in place for seasonal influenza vaccines.