Experts calculate that the new rules, which permit gay men who say they have been celibate for at least ten years to donate blood, will only increase the risk that HIV enters the blood supply by 2.5 percent:

The changes were instigated by Sabto, the advisory committee on the safety of blood, tissues and organs, which had concluded that if the ban were replaced by a new rule preventing gay men from giving blood for five years after having sex with another man, the risk of HIV reaching the blood supply would go up by less than 5%.

It is estimated that this figure would halve if the “deferral” period were increased to 10 years, so ministers backed this option. (UK Telegraph)