The incidence of cholera and malaria in South Africa is likely to increase dramatically during the next 50 years because of the effects of global warming. This is a warning from Professor Roland Schulze, of the University of KwaZulu-Natal's School of Bioresources, Engineering in Pietermaritzburg. People should begin preparing now to deal with global warming, Schulze warned, because there were already indications that climate change was affecting the country.