Detection of selected vector-borne pathogens in domestic animals, ectoparasites, and their owners in a rural community in Southwest Guatemala

Abstract

Vector-borne pathogens, which are transmitted by blood-feeding arthropods to animals and people, are common in tropical regions where, combined with economic factors, can cause significant public health burden. A community-level study was undertaken in southwestern Guatemala to assess the presence of vector-borne pathogens in blood samples from humans (n = 98), their animals (n = 90), and ectoparasites (n = 83) over a period of 2 weeks. Human capillary blood was collected from participant's index finger, and animal venous blood (chickens, pigs, dogs, and cats) was collected from the jugular or cephalic veins at the enrollment period of a concurrent study. Ectoparasites (fleas, ticks, and lice) were collected from dogs at the time of the blood collection. Total DNA was extracted from the human blood, animal blood, and ectoparasites and assayed using published PCR assays for Anaplasma spp., Bartonella spp., and Ehrlichia spp. Ectoparasites were also tested for the presence of Rickettsia spp. DNA by PCR. Anaplasma spp. DNA was amplified from 1 of 39 (2.6 %) chickens and 1 of 6 (16.6 %) turkeys. All human and dog blood samples were negative for Bartonella spp. in the same community. Ehrlichia spp. DNA was amplified from 12 (60 %) of 20 dogs and sequencing documented Ehrlichia spp. in 2 dogs and the ticks and fleas collected from these dogs. All the Ehrlichia spp.-positive sequences showed 100 % homology to E. canis sequences and other uncultured Ehrlichia spp. strains isolated from animals. Rickettsia spp. DNA was not amplified from any of the ectoparasites assessed. Our findings suggest that Ehrlichia spp. are common in dogs and Anaplasma spp. are circulating in poultry in a rural community in southwest Guatemala. We expect these results to be used in awareness campaigns and public health interventions to reduce vector borne pathogens in the region.