A new flu vaccine sprayed into the nose may be just as good as a shot in the arm, according to a study in this week's Journal of the American Medical Association. Researchers say the painless nasal spray, if approved, might convince more people to get vaccinated.
The influenza virus kills 20,000 to 40,000 mostly elderly people each year in the United States, and a bad flu season can cost more than $12 billion in lost productivity, medical care, and drugs. A safe and effective vaccine containing killed virus has been around since the 1960s, but only about a quarter of Americans each year get the shot. Taking a slightly different route, Aviron, a biotech company in Mountain View, California, designed a vaccine based on a live, inactivated virus that could be squirted into the nose as a fine mist. Last year, a study showed that the spray could slash infections in young children by 93%.
To test the nasal vaccine in adults, researchers at 13 hospitals nationwide, led by Kristin Nichol of the Veterans Affairs Medical Center in Minneapolis, gave it to more than 2800 people in fall 1997; 1400 others got a placebo. Flu vaccine production is always a bit of a gamble, and, unfortunately, the strain the researchers had chosen as a target wasn't the most virulent one roaming the U.S. that year. Despite the poor match, the vaccinated group suffered 23% fewer flulike illnesses than the placebo group, lost 18% fewer days of work, and made 25% fewer hospital visits. "We're happy to see good results," says Nichol. It's impossible to say if the new vaccine is as good as the traditional one, she says, because the two have not been compared directly yet.
Experts hope that the new vaccine, which the Food and Drug Administration is reviewing for approval, could help convince millions to get vaccinated. "The big advantage is elimination of a considerable barrier--the fear of needles," says Gregory Poland, a vaccinologist at Mayo Medical School and Foundation in Rochester, Minnesota. The nasal vaccine, he notes, still must be tested in the elderly, who are at the highest risk of dying from flu.