Key Takeaways:
- Abbott Laboratories identified HIV-1 subtype L, the first new strain in 19 years, part of the pandemic-causing M group.
- Existing diagnostic tests recognize subtype L, and antiretroviral therapies (ART) remain effective against it.
- Found in three samples from the Democratic Republic of Congo (1983, 1990, 2001), it’s likely still circulating regionally but remains rare.
- Genetic tracking ensures diagnostic accuracy and prepares for potential future mutations.
- Abbott released the subtype’s genetic sequence to aid global surveillance and research
Abbott Laboratories announced that it has identified a new subtype of the AIDS virus in three people, which the current tests can already detect. This type of classification helps scientists keep their therapeutic arsenal up to date. The purpose of genetic classification is to ensure that diagnostic tests recognize all HIV strains.
HIV Blood Test
The human immunodeficiency virus (HIV) mutates like all viruses. There are two different types of HIV viruses: HIV-1, which is responsible for almost all infections worldwide, and HIV-2.
A subtype of HIV-1
HIV-1 is genetically divided into four groups (M, N, O, and P). Within the M group, which is responsible for the pandemic, there are nine subtypes represented by letters from A to K. The subtypes are divided into four groups (M, N, O, and P). Abbott announced on Wednesday in a press release that they have identified a tenth subtype, “L”, in three people. Current antiretroviral treatments should work so far.
“As the L subtype is part of the core HIV group M, current treatments are expected to be effective against it,” explains Mary Rodgers, head of Abbott’s global virus surveillance program.
A strain that has been identified three times
This new mutation was identified in two blood samples taken in 1983 and 1990 in what is now the Democratic Republic of Congo. However, to include a subtype in the official nomenclature, an independent third case was required under the rules established in 2000.
This case was finally discovered in a third suspect sample taken in 2001. Sequencing was not possible at the time because the amount of virus was too small, Abbott explained. But thanks to new technologies, scientists have recently been able to isolate the virus and confirm that it corresponds to the 1983 and 1990 strains.
Probably still circulating in the Democratic Republic of Congo
This subtype is therefore not new. According to the researchers, it is probably still circulating in the Democratic Republic of Congo and perhaps elsewhere.
But until proven otherwise, the strain is rare and has been identified only three times. Abbott says that sequencing is available to researchers who want to find other cases.
Identifying all the strains is imperative
The purpose of genetic classification is to ensure that diagnostic tests recognize all strains. This is the case with this L subtype, confirmed by Mary Rodgers to AFP.
“This discovery underscores that to end the HIV epidemic, we must be ahead of the virus and use the latest technologies and all available means to understand its reach,” says the researcher, co-author of the study published in the Journal “Acquired Immune Deficiency Syndromes”.
FAQs:
Does this new HIV subtype require updated treatments?
No. Subtype L responds to current antiretroviral therapies (ART), as it belongs to the same M group as most global HIV strains.
How was subtype L discovered after decades?
Advanced sequencing tech enabled analysis of a 2001 sample previously deemed too low in viral load, confirming it matched older DRC cases.
Why is tracking HIV subtypes important?
Ensures diagnostic tests detect all strains and monitors mutations that could impact treatment efficacy or spread patterns.
Is subtype L a global threat?
Currently rare and localized to the DRC. Ongoing surveillance will track its prevalence and spread.
Can existing HIV tests detect subtype L?
Yes. Abbott confirms current tests identify it, critical for early diagnosis and containment.
References
Weintraub, K. (2019, November 6). First new HIV strain in 19 years identified. Scientific American. https://www.scientificamerican.com/article/first-new-hiv-strain-in-19-years-identified/
Yamaguchi, J. B., Vallari, A., McArthur, C., Sthreshley, L., Cloherty, G. A., Berg, M. G., & Rodgers, M. A. (2020). Brief report: Complete genome sequence of CG-0018a-01 establishes HIV-1 subtype L. JAIDS Journal of Acquired Immune Deficiency Syndromes, 83(3), 319–322. https://doi.org/10.1097/QAI.0000000000002246
