Article

Malaria Vectors in the Municipality of Serra do Navio, State of Amapá, Amazon Region, Brazil

Seção de Parasitologia, Instituto Evandro Chagas, Funasa, Belém, PA, 66090-000, Brasil.
Memórias do Instituto Oswaldo Cruz (Impact Factor: 1.59). 03/2001; 96(2):179-84. DOI: 10.1590/S0074-02762001000200008
Source: PubMed

ABSTRACT

We conducted a survey to determine the vectors of malaria in six localities of Serra do Navio municipality, State of Amapá, from 1990 to 1991. Malaria infection rates of 29.3%, 6.2% and 20.4% were detected by human blood smears in Colônia Agua Branca, Porto Terezinha and Arrependido, respectively. There was no malaria infection detected in Serra do Navio. Fifteen species were identified among 3,053 anopheline mosquitoes collected by human bait and 64.4% were identified as Anopheles albitarsis s.l., 16.7% An. braziliensis, 9.5% An. nuneztovari and 5.8% An. triannulatus. An. darlingi, the main vector of malaria in the Amazon region of Brazil, was scare. Using enzyme-linked immunosorbent assay (ELISA), a total positive rate of 0.8% (23/2876) was found for six species: fifteen An. albitarsis s.l., four An. nuneztovari, and one of each: An. braziliensis, An. triannulatus, An. oswaldoi and An. rangeli. Nine of 23 positive mosquitoes were infected with Plasmodium malariae, eight with P. vivax VK210, three with P. vivax VK247 and three with P. falciparum. Since An. albitarsis s.l. was collected feeding on humans, was present in the highest density and was positive by ELISA for malaria sporozoites, it probably plays an important role in malaria transmission in this area.

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Available from: David Charles Warhurst, Jul 03, 2014
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    • "The remaining factors are environmental alterations caused by anthropic activities, like in Venezuela (Moreno et al. 2007), or exogenous factors (Forattini 1987). The factors cited are temperature in the warm months of southern and southeastern Brazil (Forattini 1987), rainy season (Tadei et al. 1998;Tadei and Dutary-Thatcher 2000) and dry season or transition period (Póvoa et al. 2001;Moreno et al. 2007), which favor the high density of mosquitoes, variation in the cycle of hematophagous activity and productivity of breeding sites of immature forms. Notably among the determinant factors of local adaptation of mosquito species in heterogeneous conditions due to spatiotemporal environmental changes, are polymorphisms of chromosomal inversions, fusions and translocations , because these cytogenetic aspects favor selection due to their role in the promotion of adaptation and speciation of various organisms (Dobzhansky 1944;Coluzzi et al. 1979;Hoffmann et al. 2004). "
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