Monday, June 21, 2010

Inferior Blood

If it's OK to reject blood from gay men, what about blacks?

From 1977 to the present, have you had sexual contact with another male, even once? You'll have to answer that question, word for word, on a donor form if you want to give blood in this country. The form, authorized by the Food and Drug Administration and reaffirmed 10 days ago by an FDA advisory panel, offers three possible answers: "yes," "no," or "I am female." If you check "yes," you're done. You're forbidden to donate blood.

Why? Because, as the FDA explains, men who have had sex with men—known in the blood world as MSM—"are, as a group, at increased risk for HIV, hepatitis B and certain other infections." To protect blood recipients from this risk, your blood must be excluded.

Maybe you fooled around with a guy 30 years ago and have spent the rest of your life as a celibate priest. Maybe you've been in a faithful same-sex marriage for 40 years. Maybe you've passed an HIV test. It doesn't matter. You can't give blood, because you're in the wrong "group." On the other hand, if you're in the right group—heterosexuals—you can give blood despite dangerous behavior. If you had sex with a prostitute, an IV drug user, and an HIV-positive opposite-sex partner 13 months ago, you're good to go.
This kind of group-based screening is a long-standing practice in blood regulation. Over the years, we've prohibited donors on the basis of nationality as well as sexuality. There's nothing wrong with such categorical exclusions, according to the FDA, as long as they make the blood supply safer. But if that's true, why not screen donors by race?

The FDA bases its MSM policy on simple math. "Men who have had sex with men since 1977 have an HIV prevalence … 60 times higher than the general population," the agency observes. "Even taking into account that 75% of HIV infected men who have sex with men already know they are HIV positive and would be unlikely to donate blood," that leaves a population of MSM blood-donor applicants whose HIV prevalence is "over 15 fold higher than the general population."

So a 15-fold difference is good enough to warrant group exclusion. How about a nine-fold difference? According to the Centers for Disease Control, HIV prevalence is eight to nine times higher among blacks than among whites, and HIV incidence (the rate of new infections in a given year) is seven times higher. For black women, HIV prevalence is 18 times higher than for white women.

And these numbers understate the likely difference in risk to the blood supply. A recent CDC analysis of MSM in five cities found that while only 18 percent of the HIV-infected white men were unaware of their infections, 67 percent of the infected black men were unaware. If the awareness gap between blacks and whites overall is even half as great as it was among the men in this study—i.e., if blacks are twice as likely as whites to be unaware that they're infected, and therefore more likely to try to donate infected blood—then theoretically, black donors are just as risky as MSM donors.

Under FDA doctrine, even slight differences in average risk are sufficient to warrant group exclusions. The agency says its job is to "maximally protect" blood recipients. "Several scientific models show there would be a small but definite increased risk to people who receive blood transfusions if FDA's MSM policy were changed," it notes. Accordingly, "to err on the side of safety," MSM are excluded. A similar calculation, applied to blacks, would yield a similar result.

Is race a less legitimate basis for exclusion than sexual orientation is? Race is immutable, but plenty of evidence suggests that homosexuality is immutable, too. Technically, the MSM exclusion isn't a gay exclusion: You can be gay as long as you don't have sex with other men. A parallel policy, applied to race, would be that you can be black as long as you don't have sex with other blacks. After all, the No. 1 reason you're more likely to get infected by a gay man than by a straight one is the already high prevalence of HIV among gay men. The same is true of the higher infection risk among blacks.
Sounds crazy, right? But we already exclude blood on the basis of African origin. In 1983, the FDA ruled out donations from anyone who had lived in Haiti after 1977. Then it extended this prohibition to sub-Saharan Africa. Today, the Red Cross informs prospective donors that under FDA rules, "Persons who were born in or lived in Cameroon, Central African Republic, Chad, Congo, Equatorial Guinea, Gabon, Niger and Nigeria since 1977 cannot be blood donors."

This isn't racial animus. It's just blunt math, based on the increased risk of a particular HIV type in these populations. The FDA has a similarly coarse rule against blood from anyone who has spent half a year in the United Kingdom, based on the threat of mad-cow disease. The problem isn't racism; it's the crudity of treating individuals according to group membership. Where does it end? When the FDA barred Haitian blood, Haitian groups asked why black Americans, whose HIV rate was higher than that of Haitians, weren't similarly excluded. It was a good question, and it was never answered.

We don't have to keep going down this road. Instead of rejecting people based on group membership, we can assess them as individuals. It's fine to ask them about factors known to affect the risk of infection: travel, promiscuity, condom use, drug abuse, piercings, tattoos, whatever. But the evaluation of these factors has to be more nuanced than a categorical exclusion. And the surest measure of each individual's risk is a blood test. Even the FDA concedes that "today's highly sensitive tests fail to detect less than one in a million HIV-infected donors."

In its latest recommendations, posted Friday, the FDA's advisory committee on blood suggests further research and acknowledges that current screening policy is "suboptimal in permitting some potentially high risk donations while preventing some potentially low risk donations." But since it's unclear which "alternative policy" would be better, the panel recommends that the "indefinite deferral for men who have had sex with another man even one time since 1977 not be changed at the present time."

So the gay blood ban will continue. And that's OK, according to the American Plasma Users Coalition, whose testimony strongly influenced the FDA committee. "By their very nature, blood donor screening and deferral criteria are discriminatory; however, they are justifiable when they provide increased protection to public health," the coalition argues. "Criteria for donor deferrals must put safety of the recipient first and be based on scientific and epidemiological evidence about large groups of people."

That kind of group judgment was popular in the 19th century. It may have been necessary in the worst epidemics of the 20th. But in the 21st, we can do better.

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