This review examines the global distribution and population at risk of malaria from 1900 to 2002, using geographic information systems and historical maps. Despite human activities reducing the land area supporting malaria by half, demographic changes led to a 2 billion increase in the total population exposed to malaria risk. The study highlights that nearly 1 billion people are exposed to hypoendemic and mesoendemic malaria in southeast Asia. It also suggests that different methods used to calculate malaria burden in Africa may distort regional estimates. Population projections indicate that while population growth will not significantly change the regional distribution of people at malaria risk, around 400 million births will occur within the current distribution of malaria by 2010. The Roll Back Malaria initiative aims to halve the world's malaria burden by 2010, but the increasing difficulty of controlling malaria in high-transmission areas poses a significant challenge. The review emphasizes the need for updated global maps of malaria endemicity to better understand and address the global malaria burden.This review examines the global distribution and population at risk of malaria from 1900 to 2002, using geographic information systems and historical maps. Despite human activities reducing the land area supporting malaria by half, demographic changes led to a 2 billion increase in the total population exposed to malaria risk. The study highlights that nearly 1 billion people are exposed to hypoendemic and mesoendemic malaria in southeast Asia. It also suggests that different methods used to calculate malaria burden in Africa may distort regional estimates. Population projections indicate that while population growth will not significantly change the regional distribution of people at malaria risk, around 400 million births will occur within the current distribution of malaria by 2010. The Roll Back Malaria initiative aims to halve the world's malaria burden by 2010, but the increasing difficulty of controlling malaria in high-transmission areas poses a significant challenge. The review emphasizes the need for updated global maps of malaria endemicity to better understand and address the global malaria burden.