On September 15, the U.S. Food and Drug Administration (FDA) announced its approval of four vaccines against the H1N1, or “swine” flu, virus. According to federal officials, roughly six to seven million doses of vaccine will be available starting the first week in October, with millions more doses to be shipped in the following weeks.
The Centers for Disease Control and Prevention (CDC) reports that the rate of doctor visits for flu-like symptoms is higher than typically expected at this time of year. The vaccines currently available for three seasonal flu strains do not protect against the H1N1 virus.
Based on early data, the new H1N1 vaccines, which are available as both nasal sprays and injections, elicit an immune response in healthy adults roughly 8 to 10 days after administration. (Studies are still under way to determine the best dose for children.) For the injectable vaccine, the most common side effects include soreness at the injection site, mild fever, body aches, and fatigue for a couple of days after receiving the injection. The most common side effects of the nasal spray are runny nose, nasal congestion, sore throats in adults, and fever in children two to six years old.
Although there will eventually be enough vaccine for everyone in the United States, healthy adults are encouraged to hold off on being vaccinated so that people who are most at risk from the flu can receive the vaccine first. Those in the at-risk groups include pregnant women, people who live with or care for children under 6 months old, health-care and emergency service workers, people from 6 months to 24 years old, and those from 25 to 64 years old who have a chronic health disorder such as diabetes or a compromised immune system. Children under age two and pregnant women should not receive the nasal spray vaccine, which is made from a weakened version of the live flu virus. (The flu injection is made from inactive virus.) Additionally, the FDA notes that people who have a known allergy to chicken eggs or other substances in the vaccine should probably not be vaccinated.
Since the flu is spread primarily by the coughing and sneezing of infected people, those who have the H1N1 flu — or think they might — are advised to stay home and limit their contact with other people to prevent the spread of infection.
To learn more about the vaccines and how you can protect yourself from the flu, read “FDA Approves 4 Vaccines for 2009 H1N1 Influenza,” by Kristina Rebelo, on Medscape or see the H1N1 Web site of the CDC.