Is malaria an emerging infectious disease?
Yes. Many countries have been experiencing a resurgence in cases caused by Plasmodium falciparum, the most deadly of the four human malaria parasites. Urban migration, poverty, and poor sanitation have returned malaria to cities where it once was eliminated. New roads, logging, and irrigation have drawn people into once-isolated areas where mosquitoes thrive. Refugees, migrants, and tourists have spread the disease across borders. The seriousness of the worldwide re-emergence of malaria is made worse by the spread of parasites that are resistant to anti-malaria drugs. Parasites, like bacteria and viruses, can develop resistance to the drugs used to prevent or treat infection. Malaria parasites are increasingly resistant to chloroquine, the drug most widely used for prevention and treatment. Chloroquine-resistant strains have been reported from areas in Africa, Asia, and the Americas. The potential also exists for malaria to become re-established in the United States. Currently, about 1
