Keeping our blood supply safe


Decisions on whether to ease restrictions on blood donation must be based on science and the protection of public health, not political considerations. As obvious as that sounds, the rules of blood donation have become the topic of a social and emotional debate more than one of scientific policy. Gay men want the federal government to loosen the virtual ban on their participation, saying it stigmatizes homosexuality. Hemophiliacs, whose bleeding disorder makes them frequent recipients of blood transfusions, are pushing back.

The current policy, stemming from the early years of the AIDS epidemic, bans donations from men who have had sexual relations with another man at any time since 1977. As the gay and lesbian community gains a toehold on expanded civil rights, such as same-sex marriage, it sees this restriction as a discriminatory barrier to future progress. The nation’s blood banks, hoping for a new source of donations, are lobbying to exclude only gay men who have been sexually active in the last year. But hemophiliacs remember the agonizing period in the late 1970s and 1980s during which 10,000 people with the disorder developed AIDS because of an inadequately protected blood supply. The possibility of any liberalization of the donor rules frightens and angers many of them.

The job of the Food and Drug Administration, which has agreed to review the guidelines, is to ignore both sides -- and the pressure from senators advocating looser rules -- and to look solely at whether protection from transfusion-related illnesses would be weakened by a change. We deplore discrimination against gays and lesbians and support both same-sex marriage and an end to the military’s “don’t ask, don’t tell” policy. That’s different from having legitimate health concerns about the higher prevalence of HIV infection in sexually active gay men.


Donated blood is put through testing for various diseases, but although these tests are extremely effective and detect HIV and other diseases within a month of the donor being infected, they’re not perfect. If a certain percentage of tests give a false negative result -- or a unit of blood is accidentally released before being tested -- there is, at least theoretically, a higher danger of tainted blood entering the supply when high-risk populations are allowed to donate.

At the same time, the understandable worries of hemophiliacs should not prevent a change of rules if there is no reason to expect new dangers in the blood supply.

But the science itself is complicated and depends largely on statistical modeling to calculate theoretical probabilities. Beyond the theories, the reality is that there were only four known cases of transfusion-related HIV infection from 1999 to 2007, out of more than 112 million units of blood. In all four cases, the donors had denied having any risk factors. In addition to sexually active gay men, the high-risk groups banned from donating include anyone who was ever an intravenous drug user, people with a history or family history of certain illnesses and anyone who has ever accepted payment for sex. Other groups cannot donate for up to a year -- people who have had acupuncture or body piercings, for instance, or heterosexuals who have engaged in high-risk sexual practices.

In other words, even today’s extensiverules didn’t prevent at least a few people with HIV from giving blood or keep that blood from getting to patients. The donors might not have understood the guidelines that were reviewed with them; they might have been too embarrassed to divulge that they were in one of the risk groups; or they might have been in none of the groups but nonetheless were exposed to the virus that causes AIDS. There is no such thing as absolute, 100% safety.

That doesn’t mean the exclusions are ineffective. Studies have found that higher-risk donors generally decide against donating during the routine screening when they are told about the rules. They have no vested interest in lying; payment for blood is prohibited.

Then what would happen if the restrictions were lifted or loosened?

A 2008 report by the American Medical Assn., which reviewed a host of pertinent studies, concluded that there was a very small but statistically significant increase in risk of transmission of AIDS and other diseases if men who had abstained from sex for one year were allowed to give blood. That risk, small as it might be, is nonetheless too big. The FDA should reject a shift to a one-year abstention policy.

But the agency should seriously consider allowing donations from gay men who have abstained from sexual contact for at least five years. Under that scenario, the AMA found, the risk would be indistinguishable from current levels. The figures are theoretical, of course, based on statistical probabilities. If anything, they are probably conservative. The four transfusion-related HIV cases in recent years were a tiny fraction of what the statistical models predicted. Because not all donors remember exactly how long they have abstained from sex, the FDA should consider adding a buffer of several more years. If it does ease the restrictions, it should require immediate reporting of whether a change in policy results in more donated blood testing positive for disease.

No one should be deceived about how meaningful such a change would be. Mostly, it would give a symbolic victory to the gay and lesbian community. The number of gay men who have abstained completely from sex for at least five years is considered to be quite small. Fewer yet would be interested in donating blood. The AMA report predicts that even though changes in risk would be unnoticeable, the number of blood donors would not increase appreciably.

But that’s not a valid defense for clinging to what might be outdated guidelines. The country has more effective tests and other safety measures than when these rules were devised. If there is no reason to think the country would see a rise in transfusion- related illness with a five- to 10-year rule, refusal to relax the restriction would indeed be unfairly discriminatory.