Malaria: Past, present and future

: Malaria has always exerted a heavy toll on mankind. At the turn of the 20th century millions died each year in India alone. No other infectious disease has had more impact on the human genome, particularly in tropical regions. In the past 150 years malaria has been first controlled and then eliminated in Europe, North America and Russia. This was achieved mainly by a dual attack on the malaria vector –the anopheline mosquito, and the malaria parasite in the human host. The successes in temperate regions led to a global eradication effort endorsed by the World Health Assembly in 1955. The campaign was armed with an effective insecticide, DDT, and an excellent new antimalarial drug, chloroquine. However by 1969 it was acknowledged that the ambitious goal of global eradication could not be achieved. Over the next three decades many of the successes of the eradication effort were reversed and malaria resurged across the tropical world. The resurgence was associated with resistance to the available insecticides and to the available antimalarial drugs. The tide has turned again over the past 15 years with substantial increases in international support for malaria control activities, widescale deployment of insecticide treated mosquito nets, and the belated introduction of highly effective artemisinin combination treatments for uncomplicated malaria and artesunate for severe malaria. Global malaria mortality and morbidity have fallen substantially. Malaria eradication is now back on the agenda. The challenges now are how to maintain the political and financial support for malaria control and elimination as case numbers fall, to reach those areas where control activities are still weak, to address seriously control of P. vivax, and to overcome two looming familiar threats; insecticide and drug resistance. Resistance to pyrethroids is increasing and resistance to artemisinin in P. falciparum has emerged in South-East Asia, and now extends to the border of India. Artemisinin resistance has not been contained, and combination partner drug resistance has predictably followed. Spread of resistance to Africa would be disastrous. A moderately effective vaccine has been developed and new drugs are in the pipeline, but they will not generally available for years. The future is uncertain.