My father has been a faithful blood donor for many years, he was recently honored by the Red Cross for giving over 500 pints. He returned from vacation today and had a message on his answering machine from the Red Cross stating that they could no longer accept his blood. They said he had two false positive results for a TBH? or TVH? virus. It was hard to hear what they said on the machine. They are going to send him a letter with the details.
I did some quick web searches and found that a false positive means that a pre-screening indicates a virus is present, but a full test comes back negative. Am I correct in that understanding?
Also, I could not find anything on the TBH or TVH virus, can anyone tell me what those initials stand for or anything about the virus? Are there any other viruses close to that name that either he or the caller may have misunderstood?
He is concerned about his health, but is also disapointed that he will no longer be able to donate, something he took pride in for many years. He is going to wait for the letter and discuss it with his doctor, but asked me to find any information I could.
I just tried to find the letter I received on the same subject about seven years ago, but it’s eluding me at the moment. What probably happened is that his blood failed the initial (Western Blot?) HIV antibody test, but passed a more rigorous screening. Nevertheless, federal regulations require that anyone failing the initial screen be placed on a “may not donate” list. When I was blackballed it took two successive failures; now I believe it’s one strike and you’re out.
The letter went to great pains to reassure me that I did NOT have any form of HIV, then went on to describe all manner of behaviors that may have contributed to the false positive (mainly the sort of thing—exchanging money for sex, sharing needles, etc—that will have a potential donor rejected anyway). Since I had not engaged in any of them, the most likely culprit was an adverse reaction to a flu shot.
My sympathies to your father. His reaction is pretty much the same as mine (I hadn’t given nearly as much, but took some measure of satisfaction in that I have one of the less-common types). Hopefully, the letter will go into much greater detail.
(Oh, and IMHO leaving a message on an answering machine is a pretty shoddy way to let someone know he’s been barred from a valuable activity that he’s taken justifiable pride in.)
A false positive means that one tests positive when one doesn’t have the condition being tested for.
Why they would bar false positives is something I don’t know. Maybe back-up testing is too expensive to be practible for a large population of fals-positive recidivists.
Short version: Your Dad is fine, but the blood folks are being really, really cautious.
Somewhat longer version: The initial screening for any of a number of diseases, HIV, Hepatitis B or C, or HTLV was positive. More accurate tests were then performed and they came back negative. But * something *, probably innocuous, did trigger the false positive. Because there’s a small chance that whatever it was is a brewing infection or some other problem, the Red Cross is erring on the side of over-caution and permanently deferring the donor.