By: Valerie Miller, Ph.D.
Federal Regulatory Policy
To keep the blood supply safe, screening blood is more important than banning donors
With the recent mass shooting at Pulse, a gay night club in Orlando, many members of the LGBT community were outraged that gay men were unable to donate blood to help victims of the massacre. The federal ban on blood donations from men who have sex with men, instituted by the Food and Drug Administration (FDA), has been in place since 1983, after scientists understood the HIV disease and how it was spreading. This rule was recently scaled back in December 2015, when the FDA determined that men who have sex with men can donate, but not if they have had sexual contact with other men in the past year. The FDA continues to support a ban on men who have sex with men, because this demographic has the highest incidence of HIV infection.
Receiving a blood transfusion is extremely safe. Statistically, the risk of contracting HIV from a blood transfusion is 1 in 2 million, according to the National Institutes of Health. However, the actual incidence is much lower. Each year, more than 15 million donated pints of blood are transfused into patients. The last time anyone was known to have contracted HIV from a blood transfusion was 2008. However, experts believe this this success has little to do with donor bans, and is instead a result of advances in blood screening technology. All blood donated in the United States is federally regulated, and has been tested for HIV since 1985. Currently, donated blood is subjected to two tests for HIV, both of which are highly accurate. In a typical year, there are a few hundred cases in which donated blood tests positive for HIV.
Researchers at the FDA recently published a paper concluding that relying solely on blood testing would result in an additional 31 pints of HIV infected blood to get past the screening process, because there is a window following HIV infection and when it becomes detectible by today’s technologies, which is currently nine days. However, the FDA model is based on a complete lack of a ban, and doesn’t take into account the fact that donors themselves who participate in risky behaviors may practice self-selection. Instead, evidence suggests that it may be possible to ban donors based on risky behaviors such as unprotected sex with multiple partners, instead of focusing on the gender of sexual partners. From 2010-2013, researchers conducted a pilot study that collected information about every donor who tested positive for HIV, and found that 76% of HIV-positive donors were male, and 52.4% of those men had had sex with another man in the past year. This study indicated that men who have sex with men are already donating blood, and that half of the men whose blood tested positive had not had sex with another man in the past year. In the study, men who had sex with women were found to have a higher number of lifetime partners than men who had sex with men. At this point, no questions are asked about heterosexual partnerships during the blood donation process. A possible solution would be to make donor bans based on risky sexual behavior that apply to everyone. However, the Canadian Blood Services performed a survey of sexual behaviors on potential donors and found that many would be excluded, leading to potential blood shortages, indicating that careful consideration must be given to any potential new bans. In the meantime, the FDA recently approved the Intercept Blood System, which can reduce viruses, bacteria and pathogens that contaminate platelets, making the blood supply even safer. (Maggie Koerth-Baker, FiveThirtyEight)
Now we know what happens to teens when you make pot legal
The Colorado Department of Public Health and Environment has published the results of a new survey showing that following legalization in 2012, the rate of marijuana use among Colorado teens has remained unchanged. This survey, based on a random sample of 17,000 middle and high school students, showed that in 2015, 21% of Colorado students used marijuana in the past 30 days, which is lower than the national average, and is a slight decrease from the 25% of Colorado students who reported using marijuana in the past 30 days in 2009.
The results of these surveys are being monitored closely by policymakers on both sides of the legalization debate. Opponents of legalization have feared that more kids would smoke pot following legalization, due to increased availability. However, the data from Colorado, which includes two full years following the legalization of marijuana, indicates that adolescent use has not increased in this state. One explanation for why legalization is not increasing pot smoking among teenagers is that adolescents report that marijuana is widely available. Nationally, nearly 80% of high-school seniors report that pot is easy to obtain, indicating that those who want to smoke marijuana probably already are, which would change little following legalization. (Christopher Ingraham, The Washington Post)
Jupiter, meet Juno: NASA spacecraft settles in to begin its mission
Juno, NASA’s planetary probe sent to investigate Jupiter, has safely entered Jupiter’s orbit. NASA received confirmation of the successful orbit entry in the form of three tones, at 11:53 pm EDT on the 4th of July, following a 35-minute engine burn to slow the speed of the probe. Now that Juno has arrived at Jupiter after a 5-year journey from Earth, it will investigate the planet at 4000 kilometers above its outer veil of clouds, more closely than any spacecraft before. Juno’s mission will be to attempt to shed light on the origin and evolution of Jupiter by investigating questions such as: what structures are present below the surface clouds? Does Jupiter have a solid core? And how far do the surface stripes and storms extend into the center of the planet? Juno will begin observations in August after a 53-day orbit, and will then will orbit Jupiter 33 times over the next year and a half. At the end the mission, Juno will crash into Jupiter and disintegrate, in order to prevent accidental collision with one of Jupiter’s potentially habitable moons, which could cause contamination with microbes from Earth. (Daniel Clery, Science Magazine)
Have an interesting science policy link? Share it in the comments!