A South African woman suffering from inadequately treated HIV, and who harbored Covid-19 for nine months saw the respiratory virus develop at least 21 mutations while in her body, according to a study.

Once the 22-year-old adhered to the anti-retroviral medication used to treat HIV and her immune system strengthened she was able overcome the Covid-19 infection within six to nine weeks, the study, led by scientists from Stellenbosch and the University the University of KwaZulu-Natal showed. The research has not been peer reviewed.

The study adds to evidence that Covid-19 may mutate rapidly when harbored by immunosuppressed individuals, such as those not taking medication to treat HIV, and this may lead to the development of new variants. The beta variant, which the patient in the study was infected with, was discovered in South Africa, as was omicron.