Pune, July 6: In a significant finding, scientists at the Pune-based National AIDS Research Institute (NARI) have, for the first time, found a novel 'recombinant' strain of the HIV virus in the North East region of the country. Not only does it resemble the strain from Thailand, but scientists have expressed caution that surveillance measures need to be taken for checking the emerging strains across the country.

Presently the sub type C strain of the HIV virus is prevalent in the country. The HIV epidemic in the country has been primarily driven by sexual transmission and this finding now complicates the attempts towards defining intervention strategies, particularly in developing anti-AIDS vaccines.

Scientists at NARI have documented in the journal AIDS Research and Human Retroviruses, published in the January and February 2008 issues, novel instances of B/C recombination in HIV-1 circulating in India where the origin of two subtypes, clade C and clade B differed and resembled a form that had established a foothold in Thailand.

When contacted, Dr Ramesh Paranjape, Director of NARI, said that the emergence of the new strains could be due to cross-border migration and tourism. Further research will help us understand how effective this new combination of the B-C strain can be in transmitting the HIV virus from one individual to another, Paranjape told The Indian Express.

Due to drug trafficking in the North-Eastern region which also has a high number of injecting drug users (IDUs), there is a strong possibility of the area being susceptible to emerging strains across the border, scientists point out.

Dr Shrikant Tripathy, Deputy Director of NARI, said that if one person is infected with the Thai strain and also has the Indian strain of HIV, it is likely that that the two viruses can combine to form a recombinant or a hybrid strain. What is important now is to investigate how effective this strain can be in transmitting HIV from one individual to another, says Tripathy.

Paranjape said four blood samples taken from HIV patients in Manipur were identified with the novel HIV-1 B/C recombinant strain. If this strain is found to be widely circulating in this geographical area, then one needs to investigate as to how this virus responds to HIV treatment. These circulating recombinant forms play a major role in the global AIDS epidemic.