WASHINGTON: The discovery of a highly virulent strain of HIV in the Netherlands has been elusive for decades, but because of the effectiveness of modern treatments, Oxford researchers announced on Thursday that "there is no cause for alarm."
Their analysis, published Thursday in the journal "Science," showed that patients with what they call the "VB variant" had levels of the virus in their blood 3.5 to 5.5 times higher than those infected with other types, as well as 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 rates as individuals with other HIV forms.
"There is no cause for alarm with this new viral variant," said Oxford epidemiologist Chris Wymant, lead author on the paper in an interview with AFP.
According to the researchers, the incidence in the Netherlands most likely occurred in the late 1980s and early 1990s, but began to decline around 2010.
Since modern interventions still seem to be working on the variant, the research team believes that widespread HIV treatment in the Netherlands has not contributed to the development of the virus, and that early detection and treatment are paramount.
Co-author Christoph Fraser, an Oxford researcher, said in a press release: "Our findings emphasize the importance of the World Health Organization's guidance that individuals at risk of acquiring HIV have access to routine testing to allow early diagnosis. There is access, followed by immediate treatment." declaration of findings.
The work also supports the theory that viruses may have evolved to become more virulent, a widely hypothesized idea for which few real-world examples have been found.
The delta version of the novel coronavirus was another recent example.
"The discovery of the HIV variant should therefore be a warning that we should never be overconfident about saying that the virus will only evolve to become mild," Wymant told AFP.
In all, the team found 109 people infected with the VB variant, of whom only four lived outside the Netherlands, but still in Western Europe.
- 500 mutations -
The HIV virus is constantly evolving, so much so that each person infected has a slightly different version.
However, more than 500 mutations were found in the VB variant.
"Finding a new variant is normal, but finding a new variant with unusual properties is not -- especially one with increased virulence," Wyman explained.
The research team first identified the VB variant in 17 HIV-positive individuals, parsing a comprehensive data set from the BeeHive project, a data collection and analysis initiative in Europe and Uganda.
Because 15 of the 17 were from the Netherlands, they studied data from 6,700 HIV-positive Dutch individuals, identifying a further 92.
The earliest presence of the VB variant in their data was found in someone diagnosed in 1992 who had the early version of the variant, and most recently in 2014.
Other researchers have since found other individuals with the variant diagnosed after 2014.
Doctors usually measure the decline in the immune system of HIV by monitoring the decline of CD4 T-cells, which are targeted by the HIV virus and are important for the body's defense against infection.
In patients infected with the VB variant, CD4 decline occurred twice as fast as in other types, "putting them more rapidly at risk of developing AIDS," the researchers said.
In addition to its increasing effect on the immune system, the team also found that the VB variant is more permeable.
They came to this conclusion after comparing different versions of VB variants taken from infected patients.
The fact that they were so similar made the virus rapidly pass on to someone else before accumulating many mutations.
-For 'critical' diagnosis and prompt treatment -
"Since the VB variant causes a more rapid decline in immune system strength, it becomes important that individuals are diagnosed early and that treatment is started as soon as possible," the press statement said. .
"This limits the amount of time that HIV can damage a person's immune system and put their health at risk," Fraser said.
Fraser is also the principal investigator of the BEEHIVE project, which was launched in 2014 to gather data on how mutations in the HIV virus can cause varying degrees of severity in patients.
Those differences are previously thought to be related to the strength of most individuals' own immune systems.
The researchers said they could not identify which genetic mutation in the VB variant caused its virulence, but they hope that future studies will enable it.