Scientists have discovered a new, highly virulent HIV strain in the Netherlands. The variant has higher virulence and more damaging health impacts.
Scientists discovered the variant in an international collaborative study with key contributions from the Dutch HIV Monitoring Foundation and led by researchers from the University of Oxford‘s Big Data Institute.
This new HIV variant has been named the ‘VB variant’ (for virulent subtype B). It was first identified in 17 HIV-positive individuals from the BEEHIVE project, an ongoing study collecting samples from Europe and Uganda.
As most of these people came from the Netherlands, scientists analyzed data from a cohort of over 6,700 HIV-positive individuals in the Netherlands. This identified an additional 92 individuals with the variant from all regions of the Netherlands, bringing the total to 109.
Lead author Dr. Chris Wymant, from the University of Oxford’s Big Data Institute and Nuffield Department of Medicine, said: “Before this study, the genetics of HIV was 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.”
Scientists found that the people infected with the new “VB variant” showed significant differences before antiretroviral treatment compared with individuals infected with other HIV variants:
- Individuals with the VB variant had a viral load (the level of the virus in the blood) between 3.5 and 5.5 times higher.
- In addition, the rate of CD4 cell decline (the hallmark of immune system damage by HIV) occurred twice as fast in individuals with the VB variant, placing them at risk of developing AIDS much more rapidly.
- Individuals with the VB variant also showed an increased risk of transmitting the virus to others.
Senior author Professor Christophe Fraser from the University of Oxford’s Big Data Institute and Nuffield Department of Medicine added: “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. This limits the amount of time HIV can damage an individual’s immune system and jeopardize their health. It also ensures that HIV is suppressed as quickly as possible, which prevents transmission to other individuals.”
The variant first arose in the late 1980s and 1990s in the Netherlands. During the 2000s, it spread more quickly than other HIV variants, but its spread has been declining since around 2010.
Scientists believe that the VB variant arose despite widespread treatment in the Netherlands, not because of it since effective treatment can suppress transmission.