Natural Plasmodium infection in neotropical primates in the island of São Luís, state of Maranhão, Brazil

Abstract

The states that make up the Legal Amazon Region, which include the state of Maranhão, account for 99% of registered cases of human malaria in Brazil. It is also believed that transmission of malaria from nonhuman primates (NHP) to humans occurs in this region, because of current reports of seroepidemiological results from samples from humans and NHP coexisting in the same areas. This study aimed to make morphological, serological and molecular diagnoses of Plasmodium spp. in neotropical primates on the island of São Luís, state of Maranhão, Brazil. The diagnostic techniques used were optical microscopy, the polymerase chain reaction (PCR) and the indirect immunofluorescence assay (IFA). From June 2009 to April 2010, 70 NHP were sampled: 50 at the Wild Animal Screening Center (CETAS), located in the municipality of São Luís and 20 free-living individuals that were caught in a private reserve located in the municipality of São Jose de Ribamar, state of Maranhão. Under an optical microscope, 140 slides (two from each animal) were evaluated and five animals (7.1%) were found to be positive. IFA did not detect anti-Plasmodium spp. From PCR on the 70 animals sampled, amplified Plasmodium spp. products were observed in 13 samples, of which eight (61.5%) were from free-living animals and five (38.5%) were from animals at CETAS.

Molecular identification of Plasmodium spp. and blood meal sources of anophelines in environmental reserves on São Luís Island, state of Maranhão, Brazil

“…evansae and An. shannoni were only found in low numbers in the present study, these species are important because they have already been identified in areas of occurrence of simian malaria [38, 39, 43–45]. These mosquitoes are more commonly found in treetops [46], but specimens were caught at ground level and using human bait in the present study, thus showing the versatility or opportunism of these vectors according to the offer of hosts.…”

“…The used anti-sera probably did not differentiate blood meals originating from humans and monkeys, and additional studies, more specific for the blood source, should be developed for this mosquito [37]. Therefore, because of the presence of Neotropical primates positive for Plasmodium [38], a PCR with specific primers for Neotropical primates was recommended. In the pools of An.…”

Serological and molecular techniques applied for identification of Plasmodium spp. in blood samples from nonhuman primates

“…For diagnosing simian malaria, diagnostic techniques for human malaria are often adapted to the particularities of this type of sample, so as to deal with the low levels of antibodies and the low degrees of parasitemia that are observed in natural infections due to Plasmodium spp. in New World primates In addition, these primates present chronic infections with low degrees of parasitemia (AMERI, 2010), independently of the primate species or of the biome that they inhabit (CHINCHILLA et al, 2006;FIGUEIREDO et al, 2015). Detection of Plasmodium spp.…”

“…The sensitivity of this technique under field conditions is up to 100 parasites per microliter of blood (MYJAK et al, 2002). However, reading the slides to accurately identify mixed infections is a laborious and often difficult process (RUBIO et al, 2002), especially with the ring stage trophozoite (AMERI, 2010;FIGUEIREDO et al, 2015).…”

Plasmodium vivax and Plasmodium falciparum infection in Neotropical primates in the western Amazon, Brazil

“…The aetiological agents of human malaria also infect NHP and these mammals can act as reservoirs in different Brazilian biomes, which may have implications for public health (Araújo et al, ; Duarte et al, ; Costa et al, ; Figueiredo, Di Santini, Figueiredo, & Machado, ; Yamasaki et al,). Aetiological agents of simian malaria, such as P. brasilianum and P. simium , have also been diagnosed in Neotropical primates in Brazil (Alvarenga et al, , ; Arruda, ; Deane, ).…”