Research has suggested that HIV rates for gay men in sub-Saharan Africa are ten times higher than the average rate for the general male population.
According to the Oxford University report, published in respected medical journal the Lancet, the high rates are caused by prejudice against people.
The report’s authors suggested that this led to isolation and harassment, which in turn results in risky sexual practices.
They said rates of infection were “driven by cultural, religious and political unwillingness to accept [gay men] as equal members of society”.
Lead researcher Adrian Smith cited “profound stigma and social hostility at every level of society concerning either same-sex behaviours amongst men, or homosexuality”.
He told the BBC: “This has the consequence that this group becomes extremely hard to reach.”
Mr Smith also suggested that gay men were more likely to be involved in other risky practices, such as prostitution, intravenous drug use and having multiple partners.
The United Nations Aids agency estimates that of the 33 million people in the world who are HIV-positive, two-thirds live in sub-Saharan Africa.
In May, the Lancet criticised the UK’s policy on HIV over the estimated numbers of individuals unaware they carrying the virus.
In an editorial, the journal noted that around 21,000 people are thought to be unaware they are HIV-positive and that an increase in infection rates has been seen in both gay and straight individuals.
It argued that Department of Health recommendations for a stronger public health response have been largely ignored, despite one former senior government health official warning that the problem is an “appalling statistic”, and a “serious epidemiological issue”.