Until recently, men who had had sex with men at any point in their lives were prohibited from giving blood in the U.S., the rationale being that they were more likely to be HIV-positive. Gay men, however, weren’t all allowed to do so – a policy harking back to the height of the AIDS crisis, and one that was quickly derided as discriminatory and an insult to a community under attack. NEW YORK – In the aftermath of the shooting at a gay nightclub in Orlando that killed 49 people and injured 53, blood centers were overwhelmed with people who wanted to donate.