Gay and bisexual men have been told they cannot donate their plasma to a trial hoping to provide a treatment for Covid-19.
Doctors at London's Guy's and St Thomas's Hospital are aiming to use the plasma from recovered coronavirus patients to treat others with the disease.
It is hoped that the possible treatment, known as convalescent plasma, will help Covid-19 patients whose bodies are not producing enough antibodies to fight the disease.
But any man who has had sex with another man within the past three months is excluded from donating their plasma, in line with the current rules for donating blood.
Those guidelines explain that "men who have sex with men are at an increased risk of acquiring certain infections through sex", which could be passed on during a transfusion.
Critical care manager Andy Roberts told ITV News that he was turned down for the plasma trial, after testing positive for Covid-19.
He says that at the end of a 20 minute phone call with an operator working on the trial he was asked about his sexuality and subsequently told that he could not donate plasma due to being in a same-sex relationship.
Mr Roberts' partner Keith Ward told ITV News: "It makes me feel very angry.
"We have been together in a monogamous relationship for more than 30 years and I previously didn’t know of this outrageous three month rule.
"It only goes to show that in the UK being gay is still thought as a form of contamination, so if you’re straight and sleep with a different person every weekend it’s safer according to [the rules]."
The guidelines around donating blood are set by the Department of Health on the recommendation of the Advisory Committee on the Safety of Blood, Tissues and Organs.
They are implemented by the NHS Blood and Transplant service, which told ITV News that in relation to the plasma trial: “We will initially be using the current donor selection guidelines although we will keep this under review."
A spokesperson added: "The guidelines are there to protect the health of the donor and the recipient.
"Under the current guidelines, men must wait three months after having oral or anal sex with another man. We appreciate this deferral can feel disappointing if you want to save lives.
"Separately to the convalescent plasma trial, we are working with LGBT+ groups to explore whether we might be able to introduce a more individualised risk assessment for blood donation.”
Laura Russell, Director of Policy at Stonewall, said: “It's really upsetting that gay and bi men who want to help in the fight against coronavirus are being prevented from doing so. The decision on whether people should be able to give blood or plasma should be based on individual risk assessments, not on people's sexual orientation.”
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