OXFORD, United Kingdom — A more aggressive HIV strain that could cause patients to develop AIDS twice as fast has been discovered in the Netherlands. Despite its strength, experts aren’t sounding the alarm, saying there is no health crisis to worry about.
The new variant is highly virulent and potentially lethal without early detection, according to researchers from the University of Oxford. Individuals with an HIV infection need quick treatment, before the virus can ravage their immune system. Scientists call this variant “VB” (virulent subtype B) and add that it may also have implications for COVID-19, since continuous mutations keep fueling the ongoing pandemic.
For many years, there have been concerns this could arise in HIV and the new study appears to confirm this possibility. The AIDS-causing virus affects 38 million people worldwide and has claimed 33 million lives.
“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,” says lead author Dr. Chris Wymant in a media release.
What makes VB so much more dangerous?
Patients with VB had a viral load – the virus level in the blood – between 3.5 and 5.5 times higher than the typical HIV strain. They were also more likely to transmit the virus to others.
Moreover, the rate of decline in T cells – the hallmark of immune system damage – occurs twice as fast in patients with VB. Also known as CD4 cells, T cells are special cells in the immune system that fight off infections. By the time of a patient’s diagnosis with the new variant, they were vulnerable to full-blown AIDS within two to three years.
“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,” says senior author Professor Christophe Fraser.
Scientists first identified VB in 17 HIV-positive individuals from the BEEHIVE project that collects samples from across Europe and Uganda. Since 15 of those cases come from the Netherlands, the researchers analyzed data from a cohort of over 6,700 Dutch HIV patients.
This identified an additional 92 cases from around the country, bringing the total to 109. An analysis of genetic patterns suggests VB developed during the late 1980s or 1990s in the Netherlands. It spread more quickly than other variants during the 2000s, but cases have been declining since around 2010.
HIV researchers divide the virus into two main types – HIV-1 and HIV-2. The former is more virulent and responsible for most cases. VB belongs to a subgroup of this strain.
New HIV strain is ‘not a public health crisis’
All of these variants pass from person to person in the same ways, such as unprotected sex and sharing needles. However, researchers say some are easier to pass on than others. Study authors believe VB emerged in spite of widespread treatment and awareness campaign regarding HIV – not because of it. Effective drugs can suppress transmission.
Patients showed typical characteristics for people living with HIV in the Netherlands including age, sex, and suspected mode of transmission. This indicates the increased transmissibility is due to a property of the virus itself – rather than any differing behaviors of the people with the virus.
Reassuringly, after starting treatment, immune system recovery and survival rates were similar to those involving other strains. However, the researchers stress that VB causes a more rapid decline in immune system strength. This makes it critical individuals receive early diagnosis and treatment after an infection. Further research to understand the mechanisms could reveal new targets for next-generation antiretroviral drugs.
The study also notes VB displays many mutations throughout its genome. A single genetic cause for this is not clear at this stage.
Dr. Joel Wertheim, an HIV expert at the University of California-San Diego, who did not take part in the study, says sexually active individuals should not panic.
“Observing the emergence of more virulent and transmissible HIV is not a public health crisis,” Dr. Wertheim tells South West News Service in a statement. “Let us not forget the overreaction of the claim of ‘Super AIDS’ in 2005. Alarm was raised over a rapidly progressing, multidrug-resistant HIV infection found in New York that was ultimately restricted to a single individual.”
The findings appear in the journal Science.
South West News Service writer Mark Waghorn contributed to this report.