THE emergence of the H1N1 swine flu has added urgency to what has become an annual ritual for millions of Americans: getting a flu shot. The good news is that scientists have developed a vaccine against the H1N1 virus. But it is taking much longer than expected to produce the hundreds of millions of doses the government had planned to distribute. And it is still too soon to know how effective the vaccine will be in preventing swine flu.
In all likelihood, we'd have a better H1N1 vaccine — and more of it — if in our preparations we had accounted for the biological differences between men and women.
Under the current guidelines, men and women are to get equal-sized doses of the H1N1 vaccine. Yet women's bodies generate a stronger antibody response than men's do, research shows, so less vaccine may be needed to immunize them. If we could give women a smaller dose, there would be more vaccine to go around. And we might also spare them the mild side effects that vaccines can cause, like injection site pain, inflammation and fever. All of these are more common in women than in men.
To be clear, it is essential that women get their flu shots, even if the current dose is more than they need. Pregnant women in particular should make sure they are protected, since those who get the swine flu are at least four times as likely as others with the virus to be hospitalized. (We don't know whether pregnant women are more susceptible to the H1N1 virus, but it's clear that once they are infected, they have a higher-than-average risk of complications.)
But ultimately we should do everything we can to vaccinate as many people as possible.