Could the dissemination of H1N1 vaccine have been more efficient?

If you consider sex a more pertinent variable--possibly--suggests a recent study. Lead author Dr. Sabra Klein and crew sifted through dozens of past clinical trials in search of sex differences in immune responses to yellow fever, influenza, measles, mumps and rubella, hepatitis and herpes vaccination.

Guess what? They found em.

According to the Eurekalert press release:

"Sex can affect the frequency and severity of adverse effects of vaccination, including fever, pain and inflammation," said Sabra Klein. "This is likely due to the fact that women typically mount stronger immune responses to vaccinations compared to men. In some cases, women need substantially less of a vaccine to mount the same response as men."

Most clinical studies did not discuss sex as an important differentiation, though the data clearly showed it.

So...does this mean that we women are repeatedly over-drugged flu season after flu season?

What kind of sex differences could be contributing to our over-eager immune responses?

Maybe it's hormonal. Klein has been working with hantaviruses and influenza viruses for years, looking at how hormone differences in men and women influence their innate, humoral, and cell-mediated responses to viral vaccines. She finds males and females differentially susceptible in these studies as well.

As to exactly how hormones might affect immune response, I am unclear. (Would welcome explanations from the immunology community.)

But, I can't help but be excited by how restructuring of vaccine distribution might create more efficiency in the future.

"An understanding and appreciation of the effect of sex and pregnancy on immune responses might change the strategies used by public health officials
to start efficient vaccination programs,optimizing the timing and dose of vaccines so that the maximum number of people are immunized." added Klein.