time: early to mid 1980s
research: I've read the "Timeline of HIV/AIDS" wikipedia page, as well as a few pages of cases of people who died in the early years of the epidemic. I've read the available information on transmission, modern testing and symptoms of the disease on the website of the San Francisco AIDS Foundation. I've watched a few AIDS-themed movies from the '90s and the play "Angels in America" to get a feel for the time (though I can't find anything taking place in the UK). Still, there are a couple of medical details I can't google, because they're unfortunally still sci-fi.
The story is as follows:
I have a male character whose partner died in 1987 or 1986, of AIDS-related infections. He started this relationship sometime in the early '80s and they didn't use protection. What I want is there to be a certain possibility (but not certainty) that the partner's infection with HIV was my main character's fault. The thing is though, said main character is a time traveller and realistically, he should be vaccinated against anything the 20th century could throw at him, including HIV.
So my first un-google-able question is: Could someone who is immune against HIV still transmit the virus, for example if he wasn't exclusive with his partner for a while? I.e. he had sex with some casual hook-up who was infected, and then with his new partner, within a few days. They didn't decide they wanted a proper relationship until months later. (I'm under the impression that up till the early '80s, nobody was really using protection as a general rule amongst the gay community. Or was that different in the UK? Would it make a difference if the partner is a doctor?) The closest real-world scenario I could find was people being quite likely to transmit the virus while still in the test window period and coming up negative in tests themselves. My instinct is that the body would still need a few days to kill the virus even if he'd been vaccinated... but my last virology class was years ago and I was never much good at it. (I'm more of a bacteria expert.)
Secondly: I've found various incubation times mentioned, anywhere from 10 months to 12 years. Most of the earliest cases in the timeline have speculations attached that their infection happened about 10 years before their death. On the other hand, some people in the '80s seem to have died within a year after being diagnosed - or does that just mean that people were diagnosed only at the outbreak of AIDS back then? On the SFAF website it says that you can be free of symptoms for 10 years and more - but surely that's only with modern retroviral drugs, right? Does anyone remember what it was like before there was treatment? (The timeline said the first drug came out in 1987.) The first known case in the UK was in 1981, and I want to avoid the implication that my HIV patient (an Afro-Brit who came to the UK to study) brought the disease into the country himself. So I'd prefer if the implication wasn't automatically that he got infected around 1977 if he died in 1987. Though I could age him up and move the start of the relationship with my main character back that far if I really have to.
Third: My main character is a universal blood donor and decides to give his partner blood while continually exposing himself to the virus, in the hopes that the antibodies his body produces will help his partner survive. First of all, is this a sensible idea that a doctor (not an infectious disease secialist) and a character trained in basic field surgery and with experience with deadly flu outbreaks would come up with? I don't want this to work too well, though. (Nobody may know that my character is from the future and carries the cure for the building pandemic in his blood.) It doesn't have to work at all, I just think it would be something reasonable to try and I don't want my character to look callous by not even trying. However, if it would actually cure the partner suffering from AIDS, I'd have to ditch the whole vaccination aspect.