Molecular Detection of Zoonotic and Non-Zoonotic Pathogens from Wild Boars and Their Ticks in the Corsican Wetlands

Real-Time Microfluidic PCRs: A High-Throughput Method to Detect 48 or 96 Tick-borne Pathogens in 48 or 96 Samples

Tick-borne pathogens (TBPs) are often detected through classical molecular tools (PCR, nested PCR, real-time PCR), but these are limited in terms of the number of targeted pathogens due to the volume of DNA available for analysis. To solve this problem, in 2014 we developed a new high-throughput method based on real-time microfluidic PCRs that can detect 48 or 96 pathogens in 48 or 96 samples in a single run, such as ten species from the Borrelia burgdorferi sensu lato group. We then used this technique for large-scale epidemiological studies of TBPs in tick and animal samples on an international scale through numerous collaborative projects.

Molecular detection of vector-borne agents in wild boars (Sus scrofa) and associated ticks from Brazil, with evidence of putative new genotypes of Ehrlichia, Anaplasma and hemoplasmas

The present study aimed to investigate, by molecular techniques, the occurrence of Anaplasmataceae, Bartonellaceae, Rickettsiaceae, Mycoplasmataceae, Coxiellaceae e Babesiidae/Theileriidae agents in blood samples of free-living wild boars (Sus scrofa) and associated ticks in southeastern Brazil. For this purpose, 67 blood samples and 265 ticks (264 Amblyomma sculptum and one A. ovale) were analyzed. In the screening for Anaplasmataceae agents by a PCR assay based on the 16S rRNA gene, 5.97% blood samples and 50.54% ticks were positive. In the PCR assay for Ehrlichia spp. based on the dsb gene, 9.24% of ticks were positive. Despite the low occurrence, a possible new 16S rRNA genotype of Anaplasma sp. was detected in a wild boar's blood sample. According to phylogenetic analyses based on the groEL, gltA, sodB genes and ITS (23S-5S rRNA) intergenic region, it was found that A. sculptum and A. ovale ticks collected from wild boars carry Ehrlichia genotypes phylogenetically associated with E. ewingii, E. ruminantium, and new Ehrlichia genotypes previously detected in horses, peccaries, and ticks collected from jaguars. In the screening for hemoplasmas by a qPCR based on the 16S rRNA gene, 88.06% of blood samples and 8.69% of ticks were positive. Mycoplasma suis, M. parvum and a possible new hemoplasma genotype were detected in wild boars in southeastern Brazil. In the screening for Bartonella spp. using a nuoG-based qPCR assay, 3.8% of tick samples were positive. Phylogenetic inferences positioned four nuoG and one r gltA Bartonella sequences into the same clade as Bartonella machadoae. No blood or tick samples from wild boars showed to be positive in the qPCR for Coxiella burnetii based on the IS1111 gene. On the other hand, only 1.6% of ticks was positive in the nested PCR assay for piroplasmids based on the 18S rRNA gene. A 18S rRNA sequence detected in a pool of A. sculptum nymphs was phylogenetically close to Cytauxzoon felis sequences previously detected in cats from the United States. Rickettsia sp. closely related to R. bellii was detected in a pool of A. sculptum nymphs. This is the first report of hemoplasmas, B. machadoae and Cytauxzoon spp. in A. sculptum. Wild boars and associated ticks do not seem to participate in the epidemiological cycle of C. burnetii in the region studied. This invasive mammal species may act as a potential disperser of ticks infected with Ehrlichia spp., Bartonella spp., hemotropic mycoplasmas, and Cytauxzoon, and may bring important epidemiological implications in the transmission of bartonelosis, ehrlichiosis, hemoplasmosis, and cytauxzoonosis to humans and animals, more specifically to horses, rodents, pigs, and cats. This article is protected by copyright. All rights reserved.