Key HIV strain 'came from Haiti'

The strain of the HIV virus which predominates in the United States and Europe has been traced back to Haiti by an international team of scientists.

The strain passed from Haiti to the US in about 1969 before spreading further, says the team in the Proceedings of the US National Academy of Sciences.

They hope knowing this could help find a cure for HIV, which can lead to Aids.

"HIV-1 group M subtype B" predominates in the US, Europe, large parts of South America, Australia and Japan.

Now scientists say they know where it came from.