2006, the cabinet transferred responsibility for AIDS policy from Tshabalala-Msimang to Deputy President Phumzile Mlambo-Ngcuka, who subsequently spearheaded a new draft National Strategic Plan on HIV/AIDS. Association with denialism While president, Mbeki was also criticised for his public messaging on HIV/AIDS. He was viewed as sympathetic to or influenced by the views of a small minority of scientists who challenged the scientific consensus that HIV caused AIDS and that antiretroviral drugs were the most effective means of treatment. In an April 2000 letter to UN secretary-general Kofi Annan and the heads of state of the United States, United Kingdom, Germany, and France, Mbeki pointed to differences in how the AIDS epidemic had manifested in Africa and in the West, and committed to "the search for specific and targeted responses to the specifically African incidence of HIV-AIDS." He also defended scientists who had challenged the scientific consensus on AIDS: The letter was leaked to The Washington Post and caused controversy. During the same period, Mbeki convened a panel to investigate the cause of AIDS, staffed by researchers who believed that AIDS was caused by malnutrition and parasites as well as by orthodox researchers. In July 2000, opening the 13th International AIDS Conference in Durban, he proposed that the "disturbing phenomenon of the collapse of immune systems among millions of our people" was the result of various factors, especially poverty, and that "we could not blame everything on a single virus." It was characteristic of Mbeki's stance on HIV/AIDS to draw attention to socioeconomic differences between the West and Africa, emphasising the importance of poverty in poor health outcomes in Africa, and to insist that African countries should not be asked blindly to accept Western scientific theories and policy models. Commentators speculate that his stance was motivated by suspicion of the West and was a response to what he perceived as racist stereotypes of the continent and its people. For example, in October 2001, in a speech at the University of Fort Hare, he said of the West: "Convinced that we are but natural-born, promiscuous carriers of germs, unique in the world, they proclaim that our continent is doomed to an inevitable mortal end because of our unconquerable devotion to the sin of lust." Mbeki announced in October 2000 that he would withdraw from the public debate on HIV/AIDS science, and in 2002 his cabinet staunchly affirmed that HIV causes AIDS. However,