Men who have sex with men are at least 44 times more likely to be diagnosed with HIV than other men, and 40 times more likely than women, according to an analysis released this week by the Centers for Disease Control and Prevention at the 2010 National STD Prevention Conference.

They also are more than 46 times as likely to have syphilis than other men and more than 71 times as likely than women to have that sexually transmitted disease.

Kevin Fenton, who heads up the CDC's efforts in those areas and is openly gay, said the analysis was made to show "just how stark the health disparities are between this and other populations."

"It is clear that we will not be able to stop the U.S. HIV epidemic until every affected community, along with health officials nationwide, prioritize the needs of gay and bisexual men with HIV prevention efforts," Fenton said.

"There is no single or simple solution for reducing HIV and syphilis rates among gay and bisexual men. We need intensified prevention efforts that are as diverse as the gay community itself," Fenton said in a prepared statement.

There was no new data, just a new analysis, and some assumptions behind it that some might question.

All broad, national analyses of gay and bisexual men have been hampered by the question of the denominator: just how does one define those categories and how many of them are there in the country?

The CDC's answer was to make two assumptions and computations. Under the first it assumed that MSM are 4 percent of the population and arrived at those conclusions. Under the second, it assumed that MSM are only 2 percent of the population, and the numbers doubled; the ratios were twice as bad.

But what if the assumptions are wrong and MSM are a larger part of the population? The famous Kinsey study found that about 30 percent of all men had at least one same-sex encounter at some point in their lives. If the number of MSM really is larger than 4 percent, the ratios would drop, perhaps precipitously.

The CDC had a telephone news conference on March 9, the day prior to release of this new analysis. But the focus was on herpes studies. Reporters were told ahead of time that the MSM analysis was off limits, questions would not be answered about it, even if outlets promised not to publish stories on the results until after the study was presented the next afternoon.