Infectious and parasitic diseases such as acute lower respiratory diseases, tuberculosis, diarrhoea, HIV/AIDS and malaria were responsible for at least 75 per cent of the 50 million deaths that occurred worldwide in 1997, according to the World Health Organisation. While deaths due to circulatory diseases came down from 51 per cent to 46 per cent in the developed world during the period 1985-1997, they increased from 16 per cent to 24 per cent in the developing world. Cancer deaths went up from six per cent to nine per cent in the developing world and formed a constant proportion of 21 per cent of total deaths in the developed world.