Authorities are desperate for people to come forward and donate blood after the shooting in Orlando that killed 50 and injured 53 – but gay men are being turned away.
The rules state that any man who in the past year has had sex with another man cannot donate blood.
Based on Food and Drug Administration rules, it has left gay and bisexual men being turned away after the LGBT nightclub shooting by Omar Mateen on Sunday morning.
The rule dates back to 1985,UK Mirror reports.
It was initially introduced as a reaction to AIDS, however while the rules have since been updated – stating that only gay and bisexual men who have had sex in the past year cannot donate blood – the revision of the law is having little practical impact.
Initially there were reports from MSNBC that an Orlando blood centre had lifted the ban.
However the centre, OneBlood, denied that the law was being ignored.