Malaria control in an agro-industrial settlement of Rondonia (Western Amazon Region, Brazil)

A malaria control pilot project was developed in the Urupa agro-industrial farm that is situated in the State of Rondonia (Western Amazon Region, Braz il). Around 180 inhabitants had been surveyed for the past five years. The control measures were based on (1) training a community agent to perform on the spot microscopical diagnosis of malaria and to treat the uncomplicated cases of malaria; (2) limiting the use of insecticides to a short period b efore the high transmission season. This resulted in a significant reductio n in the time between the onset of clinical symptoms and specific chemother apy which fell from 3.5 to 1.3 days. In relation to the previous three refe rence years the total number of malaria cases was reduced to 50% in the fir st year and to 25% in the second year. The introduction of these measures c oincided with pronounced reduction in the frequency of Plasmodium falciparu m infections but this was less marked for P. vivax infections. In the secon d year of the pilot experiment there was no P. falciparum transmission on t he farm. During the last decade there was a general decrease in the endemic ity of malaria in the State of Rondonia. The linear regression coefficient values indicate that the decline was more pronounced in Urupa than in the g eneral municipality and that the falciparum malaria API in Urupa farm is si gnificantly lower than in the general municipality of Candeias were the far m is situated.