Article

Malaria and Hepatocystis species in wild macaques, southern Thailand.

Department of Biology, Faculty of Science, Naresuan University, Pitsanulok Province, Thailand.
The American journal of tropical medicine and hygiene (impact factor: 2.59). 05/2008; 78(4):646-53. pp.646-53
Source: PubMed

ABSTRACT Southeast Asian macaques are natural hosts for a number of nonhuman primate malaria parasites; some of these can cause diseases in humans. We conducted a cross-sectional survey by collecting 99 blood samples from Macaca fascicularis in southern Thailand. Giemsa-stained blood films showed five (5.1%) positive samples and six (6.1%) isolates had positive test results by polymerase chain reaction. A phylogenetic tree inferred from the A-type sequences of the small subunit ribosomal RNA gene confirmed Plasmodium inui in five macaques; one of these macaques was co-infected with P. coatneyi. Hepatocystis, a hemoprotozoan parasite transmitted by Culicoides, was identified in an isolate that was confirmed by analysis of mitochondrial cytochrome b sequences. All malaria-infected monkeys lived in mangrove forests, but no infected monkeys were found in an urban area. These findings indicate regional differences in malaria distribution among these macaques, as well as differences in potential risk of disease transmission to humans.

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Keywords

99 blood samples
 
cross-sectional survey
 
Culicoides
 
Giemsa-stained blood films
 
Hepatocystis
 
macaques
 
malaria distribution
 
malaria-infected monkeys
 
mangrove forests
 
mitochondrial cytochrome b sequences
 
nonhuman primate malaria parasites
 
phylogenetic tree inferred
 
Plasmodium inui
 
polymerase chain reaction
 
small subunit ribosomal RNA gene
 
Southeast Asian macaques
 
urban area