Preliminary Parasitic Survey of the Natural Primate Reservoirs of Potential Zoonoses in Sri Lanka

M. A. Huffman, C. A. D. Nahallage, S. Ekanayake, H. Hasegawa, L. D. G. G. De Silva, I. R. K. Athauda


Given the close genetic relatedness of non-human primates and humans, it hasbeen reported that 25% of all micro- and macro-parasites known in wild primates havealso been reported in humans. The goal of our study was to investigate the diversity ofintestinal parasitic infections among Sri Lanka’s three diurnal primate species (the toquemacaque (Macaca sinica), purple-faced langur (Trachypithecus vetulus) and the graylangur (Semnopithecus priam thersites) across the country by sampling representativeforest reserves and public areas of human - monkey cohabitation in order to evaluate thepotential for zoonotic transmission.

The study was carried out during the rainy season in the months of February –March in 2007 and 2009 and in December of 2010. Ninety-three fecal samples werecollected at 44 locations from representative altitudinal / climatic zones across thecountry where toque macaques (64 samples), grey langurs (21 samples) and purple facelangurs (10 samples) are known to naturally occur. The cysts of Entamoeba coli andEntamoeba histolytica / dispar and the eggs of Trichuris sp. and hookworm wererecovered. The two most prevalent species found from all samples was Trichuris sp.(28%) and E. coli (26%), and they were most commonly found in the two langurspecies. The least commonly found parasite in all three species was hookworm (23%),being totally absent from the mostly arboreal purple face langur and highest in thelargely terrestrial toque macaque. Notably, hookworms were present in 23% of the greylangur samples and 33% of the toque macaque samples collected. Variability inprevalence levels across altitudinal/climatic zones was noted. For toque macaques,overall group prevalence values decreased with increasing altitude, with the highestvalues found in the intermediate to arid lowland zones, decreasing in the upland wetzone, with only Trichuris sp. and hookworm found in the highland / wet zone.

Key words: Human-safety, Zoonoses, Primate conservation, Parasitology

Full Text:



  • There are currently no refbacks.