Incidence of malaria drops in many African countries; CO2 blamed

BBC News - Mosquitoes 'disappearing' in some parts of Africa

Malaria-carrying mosquitoes are disappearing in some parts of Africa, but scientists are unsure as to why.
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Data from countries such as Tanzania, Eritrea, Rwanda, Kenya and Zambia all indicate that the incidence of malaria is dropping fast.
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One possibility for the reduction in numbers is climate change. Patterns of rainfall in these years were more chaotic in these regions of Tanzania and often fell outside the rainy season. The scientists say this may have disturbed the natural cycle of mosquito development.