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There's a review article on the effect of Papaya extracts in the treatment of Dengue fever, the main issue being thrombocytopaenia. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4071726/
The best data quoted from that paper says:
A study conducted in Malaysia had a more systematic approach in evaluating the use of papaya leaf juice in the treatment of ...
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Mosquitos transmit the pathogens that cause malaria, filariasis, dengue, yellow fever, West Nile fever, Rift Valley fever, and dozens of other infectious diseases of humans, domestic animals, and wildlife
Ross, Macdonald, and a Theory for the Dynamics and Control of Mosquito-Transmitted Pathogens
You already mentioned malaria and West Nile. The others ...
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