2. 7 Reinfection with HIV
Reinfection decribes when someone who is already HIV positive becomes infected with a new strain of HIV. Sometimes this is referred to as HIV superinfection.
There have been many reports of cases of HIV reinfection.
This was controversial because for many years it was assumed that once you had been infected with HIV, reinfection was not a risk.
It is not clear how often reinfection occurs, or what the risk factors for reinfection are.
Most studies suggest that the risk of reinfection are likely to be similar to the original risk of infection. Viral load is probably the most important risk factor for reinfection, with very high viral loads having the highest risk.
Although reinfection was first reported in early infection, cases have also been reported in chronic infection.
They included examples where someone on treatment has been reinfected by someone with drug resistant HIV, and where the treatment then stopped working.
Drug resistance is the major risk from reinfection.
Two people with the same non-resistant virus, or with the same resistant virus would not risk the same difficulties from reinfection, as someone who is reinfected with drug resistant virus.
If two HIV positive people have the same virus and the same resistance, then reinfection is unlikely to directly affect either their health or the effectiveness of treatment.
If one of the partners develops drug resistance on treatment, this risk would change.
Last updated: 1 January 2016.