Scientists have discovered a highly virulent strain of the human immunodeficiency virus (HIV), called the ‘VB variant’, in the Netherlands.
The human immunodeficiency virus (HIV) has claimed more than 35 million lives worldwide. Typically, the virus attacks a person’s immune cells and makes them prone to common infections. Since the virus poses a major public health concern, researchers have been monitoring its virulence and spread to improve HIV care across the world. The ongoing BEEHIVE (Bridging the Epidemiology and Evolution of HIV in Europe) Project in particular aims to track the mutations associated with a higher viral load. It collects samples from across Europe and Uganda. Recently, researchers at Oxford University analyzed data from the BEEHIVE project and discovered a new, highly virulent HIV strain. They published their findings in the journal Science.
According to the study authors, the new virulent subtype first originated in the Netherlands in the late 1990s. Although it initially spread quicker than other HIV variants, since 2001 its spread has declined. In the study, researchers looked at the variant’s transmissibility, evolution, response to treatment, and effect on CD4 cells.
Before this study, the genetics of the HIV virus were known to be relevant for virulence, implying that the evolution of a new variant could change its impact on health. Discovery of the VB variant demonstrated this, providing a rare example of the risk posed by viral virulence evolution.
Dr. Chris Wymant, lead author
5 Times Higher Viral Load
Initially, researchers identified the VB variant in 17 samples from the BEEHIVE Project. Due to a high majority of these cases coming from the Netherlands, the team analyzed further data from over 6,000 HIV-positive individuals in the Netherlands. This resulted in the discovery of a further 92 VB variant-infected individuals. Thus, the team discovered a total of 109 cases.
Individuals with the VB variant had a 3.5 to 5.5 times higher viral load. Their CD2 cell levels declined at a higher rate; thus, increasing their risk of developing AIDS. Moreover, these individuals showed an increased risk of transmitting the virus to other. However, despite these characteristics, antiretroviral therapy resulted in a similar immune system recovery than individuals infected with other HIV variants. Therefore, the study authors conclude that the new variant does not pose a threat to current HIV treatments.
Our findings emphasize the importance of World Health Organization guidance that individuals at risk of acquiring HIV have access to regular testing to allow early diagnosis, followed by immediate treatment
Dr. Chris Wymant, lead author
According to study authors, further studies on the variant’s mechanism can help researchers identify new targets for HIV drugs.
Reference:
Chris Wymant et al, A highly virulent variant of HIV-1 circulating in the Netherlands, Science (2022). DOI: 10.1126/science.abk1688. www.science.org/doi/10.1126/science.abk1688
