Genetic variations in the HIV strains in Africa make it more difficult for the anti AIDS drugs to act on them according to researchers. This however does not mean that these drugs will be powerless against the virus but these drugs find it difficult to latch on to the protease, which is an enzyme useful in the replication of the virus inside the body.
If the drug attaches itself to the protease, then it is easier for the drug to deactivate the virus. This is difficult in two African strains called A and C subtypes of HIV, the researchers say.Dr. Ernesto Freire of Johns Hopkins University in Baltimore, Maryland headed the team of researchers.
The commonest strain of HIV in the U.S. and other Western countries is HIV-B. But the majority of people infected with HIV live in sub-Saharan Africa. HIV-A is the dominant strain in the northern region of sub-Saharan Africa, and HIV-C is more common in southern parts of Africa.
Protease inhibitors, the drugs used in combination therapy to fight HIV infection, were all designed to treat HIV-B. These findings find a place in a report in the May 22nd issue of the journal - Proceedings of the National Academy of Sciences. Comparing the protease inhibitor to a key and the protease to a lock, Dr. Freire said when there are new strains of the virus, the key will not fit the lock and hence it will be difficult to control the burgeoning AIDS situation in Africa. But he hopes that by adapting to the changes in the protease, a drug can be developed that would be effective against various subtypes of HIV as well as varieties that have become resistant to drug therapy.
