Extreme TB strain threatens HIV victims worldwide

An outbreak of virulent and very drug-resistant tuberculosis in South Africans with Human immunodeficiency virus (HIV) is horrifying health professionals and prompting the usually slow-and-steady field of tuberculosis medicine into emergency action. The new strain, called extreme drug-resistant tuberculosis (XDR TB), is virtually untreatable. Neither the standard drugs nor at least three of the six classes of more toxic and less-effective backup drugs are effective. All of those infected with the strain have HIV and it is feared that the infection will spread north where HIV levels are high.