Scientists Have Discovered the First New Strain of HIV in 19 Years

For the first time in nearly two decades, a team of scientists have discovered a new strain of HIV. However, experts say there is no cause for alarm.

According to a report published Wednesday in the Journal of Acquired Immune Deficiency Syndromes, researchers with Abbott Laboratories and the University of Missouri, Kansas City discovered a new strain of the human immunodeficiency virus related to the Group M version of HIV-1. There are two types of the virus: HIV-1 and HIV-2, the latter of which is relatively rare. Of the four strains of HIV-1 -- Groups M, N, O, and P -- the former is responsible for the vast majority of HIV cases worldwide.

In order to be classified as a new subtype of HIV, scientists have to identify three independent cases. Researchers told CNN they have done so: two samples were discovered in the Democratic Republic of Congo 1983 and 1990, while a third was located in the African nation in 2001.

Mary Rodgers, a coauthor of the study, told the network that identifying the strain as an entirely new subtype of the virus proved a "real challenge for diagnostic tests," which is why its existence is only coming to light now.

"The sample was small, and while it seemed similar to the two older samples, scientists wanted to test the whole genome to be sure," CNN reports. "At the time, there wasn't technology to determine if this was [a] new subtype. So scientists at Abbott and the University of Missouri developed new techniques to study and map the 2001 sample."

Rodgers says the nearly decades-long process of verifying the strain's existence was akin to "searching for a needle in a haystack" and then removing the needle "with a magnet" afterward.

The strain is now known as subtype L, the 10th strain of Group M. Different subtypes can also combine to form a "circulating recombinant form," also known as a CRF. According to the international HIV/AIDS nonprofit Avert, there are currently 89 known CRFs but could be more in the future as the virus continues to evolve over time.

HIV/AIDS experts caution the public not to overreact to news of the existence of subtype L, especially given how few identified cases there have been.

"There's no reason to panic or even to worry about it a little bit," Anthony Fauci, the director of the National Institute of Allergy and Infectious Diseases, told CNN. "Not a lot of people are infected with this. This is an outlier."

Not much is known about how subtype L might affect individuals differently than other strains. However, scientists are confident that with enormous advances in medical technology since the New York Times reported on a "rare cancer seen in 41 homosexuals" in July 1981, they will be able to effectively test for and treat the recently verified subtype.

"This discovery reminds us that to end the HIV pandemic, we must continue to out think this continuously changing virus and use the latest advancements in technology and resources to monitor its evolution," study co-author Dr. Carole McArthur told CNN.

According to estimates, 37.9 million people across the world are currently living with HIV, while 1.7 million individuals contracted the virus last year. HIV can be effectively monitored by taking daily medication, which reduces the presence of the virus in the bloodstream. Meanwhile, taking pre-exposure prophylaxis (PrEP) drugs minimizes the risk of contracting HIV through intercourse by 90 percent.

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