39.TB Makes a Scary Comeback
An outbreak in South Africa of an extremely drug-resistant strain of the tuberculosis bacterium is raising international alarm. While the incidence of highly drug-resistant tuberculosis in the United States is still negligible, the disease is gaining ground in countries where large numbers of people have immune systems weakened by HIV. In healthy individuals, the TB bacterium can hide in white blood cells and remain dormant for years, but among those with a suppressed immune system, the bacillus can take off. In 2006 the virulent strain killed a cluster of 120 rural HIV-infected South Africans.
