Scientists announced Wednesday that they had discovered a new strain of HIV, the virus that causes AIDS, for the first time in nearly 20 years.

A study published in the Journal of Acquired Immune Deficiency Syndromes and first reported by CNN found that the new subtype, dubbed HIV-1 subtype L, is the first new strain of the virus to be identified since 2000.

"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 with the University of Missouri, Kansas City told CNN.

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Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, cautioned that the official recognition of the new strain was not a cause for alarm.

"There's no reason to panic or even to worry about it a little bit," he told CNN. "Not a lot of people are infected with this. This is an outlier."

Guidelines for identifying new strains of the HIV virus require three cases to be identified: two previous cases of HIV, in 1983 and 1990, have now been identified as resulting from the HIV-1 subtype L strain.

It's not currently known if the new subtype affects patients with the disease any differently, and it is thought that the strain responds to existing HIV treatments that can drive the virus to undetectable levels in the body.