2. Current or Former Sexual Partner of Affected Individual

Must not donate 

1. If it is more than three months since last sexual contact and a validated test for anti-HTLV antibodies is to be undertaken on the donated component(s), accept
2. If it is more than three months since last sexual contact, the donor has been previously tested for anti-HTLV antibodies by the blood service and this test was performed at least three months after the last sexual contact, accept
 

Blood Safety Entry

HTLV infection can be spread through sexual activity. It may however not be transmitted for a long time into a relationship. This could be because the infection becomes more active in the infected partner, the uninfected partner acquires another infection or an injury to a mucous membrane, or there is a change in the use of, or failure of, barrier contraceptives (condoms etc.). In the early stages of infection the testing used by the Blood Services may not detect the virus allowing it to be passed on by transfusion.
Waiting three months from the last sexual contact will ensure that any infection is picked up by the tests used by the Blood Services.
Blood services in the UK are not required to test all donations for anti-HTLV antibodies. Blood services will need to identify at risk donors at health screening and consider options for discretionary HTLV testing. Otherwise, donors who report sexual contact with an affected individual must be deferred.
 

This is a requirement of the Blood Safety and Quality Regulations 2005.

See below