Oxford researchers identify a new highly virulent HIV strain, stating there is no need to be alarmed due to the effectiveness of modern treatments over the variant.
Oxford researchers have announced the discovery of a highly virulent strain of HIV that has been lurking in the Netherlands for decades.
Their analysis, published on Thursday in the journal "Science," found that patients infected with the "VB variant" had 3.5 to 5.5 times higher levels of the virus in their blood than those infected with other variants.
In addition, those with the new variant had a more rapidly fading immune system.
However, the study also found that after starting treatment, individuals with the VB variant had similar immune system recovery and survival to individuals with other HIV variants.
"There's no cause for alarm with this new viral variant," said Oxford epidemiologist Chris Wymant, the lead author on the paper, in an interview with the AFP news agency.
Since modern interventions still seem to work on the variant, the research team believes that widespread HIV treatment in the Netherlands did not contribute to the virus's evolution and that early detection and treatment are paramount.
In total, the team found 109 people infected with the VB variant, with only four living outside the Netherlands, but still in western Europe.
Over 500 mutations
The HIV virus is constantly evolving, so much so that each person infected has a slightly different version.
The VB variant, however, was found to have over 500 mutations.
"Finding a new variant is normal, but finding a new variant with unusual properties is not – especially one with increased virulence," Wyman explained.
The earliest appearance of the VB variant in their data was found in someone diagnosed in 1992 who had an early version of the variant, and the most recent in 2014.
Doctors usually measure HIV's deterioration of the immune system by monitoring the decline of CD4 T-cells, which are targeted by the HIV virus and pivotal for protecting the body against infections.
In patients infected with the VB variant, CD4 decline occurred twice as fast compared to other variants, "placing them at risk of developing AIDS much more rapidly," the researchers said.
In addition to its increased impact on the immune system, the team also found the VB variant to be more highly transmissible.
The work also supports the theory that viruses can evolve to become more virulent, a widely-hypothesised idea for which few real-world examples have been found.