Strains from Group M are the most common in humans and are responsible for the global AIDS pandemic. M strains have infected about 90% of the 37.9 million people that the World Health Organization estimated were living with HIV last year. Group O, N and P infections are rare but can also affect humans.
Wednesday’s Abbott Labs findings have established a 10th group M strain. The three people who are known to carry it live in what is now the Democratic Republic of Congo, where the first HIV infection surfaced in a human in the mid-1900s. Decades later, the virus spread rapidly around the globe....