Eight hunting dogs were visited by a state veterinarian on the island of Tobago, Trinidad and Tobago, West Indies, as owners reported anorexia and paralysis in five of their dogs. The veterinarian observed a combination of clinical signs consistent with tick-borne illness, including fever, anorexia, anaemia, lethargy and paralysis. Blood and ticks were collected from each dog and submitted to a diagnostic laboratory for analysis. Microscopic analysis revealed a mixed infection of intracytoplasmic organisms consistent with Babesia spp. (erythrocyte) and Ehrlichia spp. (monocyte), respectively, from one dog, while a complete blood count indicated a regenerative anaemia (n = 1; 12.5%), non-regenerative anaemia (n = 4; 50%), neutrophilia (n = 3; 37.5%), lymphocytosis (n = 2; 25%), thrombocytopaenia (n = 3; 37.5%) and pancytopaenia (n = 1; 12.5%). DNA isolated from the eight blood samples and 20 ticks (16 Rhipicephalus sanguineus and 4 Amblyomma ovale) were subjected to conventional PCR and next-generation sequencing of the 16S rRNA and 18S rRNA gene for Anaplasma/Ehrlichia and Babesia/Theileria/Hepatozoon, respectively. The DNA of Ehrlichia spp., closely related to Ehrlichia canis, was detected in the blood of three dogs (37.5%), Anaplasma spp., closely related to Anaplasma marginale, in two (25%), Babesia vogeli in one dog (12.5%) and seven ticks (35%) and Hepatozoon canis and Anaplasma spp., in one tick (5%), respectively. These findings highlight the need to test both the vector and host for the presence of tick-borne pathogens when undertaking diagnostic investigations. Further studies are also warranted to elucidate the susceptibility of canids to Anaplasma marginale.

Background: Ticks are important vectors of many pathogens that have contributed to the morbidity and mortality of humans and domestic animals worldwide. Wildlife species have also been implicated as reservoir hosts of a variety of tick-borne pathogens. The objective of this study was to determine which tick-transmitted pathogens were present in the animals harvested from the forest in Trinidad for human consumption. Methods: Thin blood smears from 43 neotropical animals were examined microscopically for tick-borne pathogens. Additionally, DNA extraction and PCR amplification of the 16S rRNA gene were used for amplification of Anaplasma and Ehrlichia while the gltA gene was used for Bartonella, and Rickettsia spp. and the 18S rRNA gene for Babesia, Hepatozoon and Theileria species. Results: Pathogen DNA was amplified from four samples (a deer, collared peccary and two agoutis). Sequencing of the amplified products from the deer and collared peccary revealed 99.8% homology to Anaplasma bovis and 98.8% homology to Ehrlichia canis, respectively. Sequences from two agoutis revealed 90.4% homology to Theileria spp. DNA of Hepatozoon spp., Bartonella spp. Babesia spp. and Rickettsia spp. was not detected in any of the screened samples. An incidental finding in this study was the presence of bacteria in the blood of animals. Conclusions: The results indicate that the DNA of tick-transmitted pathogens is present at a frequency of about 10% in the study population and suggests that neotropical mammals may serve as a source for the potential transmission of tick-borne pathogens to domestic animals and humans. In addition, physicians and hunters should be aware of the symptoms associated with zoonotic tick-borne pathogens so that these infections can be recognised, diagnosed and treated promptly. Bacteria present in carcasses can pose a food safety hazard and hunters should be trained in proper harvesting and handling of carcasses. Graphical