A new HIV strain—known as HIV-1, group P—has been discovered in an African woman, Bloomberg reports. Originally from Cameroon, the 62-year-old woman currently resides in Paris. She has no AIDS-related symptoms.

According to the article, the discovery was published in the journal Nature by researchers at the University of Rouen in France. Researchers believe that this strain was first transmitted to humans from gorillas, not chimpanzees. Previous cases of HIV-1 are believed to have originated in chimpanzees and spread to humans when people slaughtered and ate the animals.

The new HIV strain is closely related to the simian immunodeficiency virus-gorilla, or SIVgor. However, the woman most likely contracted the virus from a human. She reported no contact with gorillas, including bush meat. Also, the virus, which can’t be detected by conventional HIV tests, showed signs of adapting to human cells.