Dr. Andrew Redd
said there are HIV infections and then there are superinfections.
"A superinfection occurs when an individual is initially infected with a strain or strains of HIV.
And then at some point later on - after that person has developed an initial immune response to their first infecting strain - at that later time point they come into contact through risky behavior with a second viral strain and then are superinfected with that second strain," he
is the lead author of the study and a scientist at the National Institute of Allergy and Infectious Diseases
said prior to the research done in Uganda it was thought that superinfections were rare, occurring in intravenous drug users or men who have sex with men.
"What we found in our study was that when we looked at a general population of heterosexual individuals in Uganda we found that it actually isn't as rare as what we thought.
And that it is occurring at a significant rate even in the general population," he
And in Uganda, we have subtype A and subtype D," said Redd
says, though, that standard antiretroviral treatment should be effective against superinfections.
"We have no evidence so far and we don't think that HIV superinfection affects the response to treatment.
From what we can tell, individuals who get superinfected respond to treatment just fine and it lowers their viral load and they get healthier.
One of the things that we're worried about, though, if the possibility that an individual could get superinfected with a viral strain that is already resistant to the antiretroviral drugs and that would be a major problem.
But to date that doesn't seem to be a huge risk so far," said Redd
added that current HIV vaccine strategies that try to "recreate the natural immune response may be insufficient to protect an individual from infection."