AIDS
Scientists have discovered a new strain of HIV (human immunodeficiency virus) that takes comparatively lesser time to develop into AIDS than the other strains associated with the deadly disease.Jayel Aheram/Flickr

Scientists have discovered a new strain of HIV (human immunodeficiency virus) that takes comparatively lesser time to develop into AIDS, than the other strains associated with the deadly disease.

The aggressive type of HIV strain, discovered in West Africa, needs less than five years from infection to develop into AIDS (acquired immunodeficiency syndrome), which is the shortest time ever recorded among HIV-1 types across the whole globe.

Till date, more than 60 strains of HIV-1 have been identified. The new strain known as A3/02 is a recombination of two common forms of HIV in West Africa, known as 02AG and A3.  

New strains of HIV are created when a person gets infected with two different types of strains, eventually leading the strains to fuse together.

The new strain of HIV is more aggressive than its parental strains. The A3/02 strain takes only five years to develop into AIDS, ultimately claiming lives by the eight year, compared to the development into AIDS and AIDS-related deaths in 02AG (6.2 and 9.0 years )and A3 strains ( 7.2 and 11.3 years).

"Infection with A3/02 was associated with a close to 3-fold increased risk of AIDS and AIDS-related death compared to A3," the authors, wrote.

Findings are based on the initiative taken by a team of Swedish researchers from the Lund University and Joakim Esbjörnsson from the University of Oxford.  For the study, the researchers included HIV-infected people in Guinea-Bissau, West Africa and followed them for many years.

Though, the strain is discovered only in West Africa, researchers warned that they can spread to other parts of the world.

"HIV is an extremely dynamic and variable virus. New subtypes and recombinant forms of HIV-1 have been introduced to our part of the world, and it is highly likely that there are a large number of circulating recombinants of which we know little or nothing," Patrik Medstrand, Professor of Clinical Virology at Lund University, said in a statement. "We therefore need to be aware of how the HIV-1 epidemic changes over time."

The study has been published in the Journal of Infectious Diseases.

The findings come at a time when the world is observing 1 December as World AIDS Day. According to the World Health Organization (WHO), nearly 34 million people were diagnosed with HIV (human immunodeficiency virus) in 2011 and 1.7 million died of AIDS.