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Ticks are obligate blood-feeding ectoparasites notorious for their role as vectors for various pathogens, posing health risks to pets, livestock, wildlife, and humans. Wildlife also notably serves as reservoir hosts for tick-borne pathogens and plays a pivotal role in the maintenance and dissemination of these pathogenic agents within ecosystems. This study investigated the diversity of ticks and pathogens in wildlife and their habitat by examining ticks collected at Khao Kheow Open Zoo, Chonburi Province, Thailand. Tick samples were collected for 1 year from March 2021 to March 2022 by vegetation dragging and direct sampling from wildlife. A total of 10,436 ticks or 449 tick pools (1-50 ticks per pool) underwent screening for pathogen presence through conventional PCR and DNA sequencing. Out of the 298 samples (66.37%) where bacteria and protozoa were detected, encompassing 8,144 ticks at all stages, 114 positive samples from the PCR screenings were specifically chosen for detailed nucleotide sequencing and comprehensive analysis. Four species of ticks were conclusively identified through the application of PCR, namely, Rhipicephalus microplus, Dermacentor auratus, Haemaphysalis lagrangei, and Haemaphysalis wellingtoni. The highest infection rate recorded was for Anaplasma spp. at 55.23% (248/449), followed by Babesia spp. and Theileria spp. at 29.62% (133/449) and 16.26% (73/449), respectively. Among bacteria identified, three Anaplasma genotypes were closely related to an unidentified Anaplasma spp., A. phagocytophilum, and A. bovis. Among protozoa, only an unidentified Babesia spp. was found, whereas two Theileria genotypes found were closely related to unidentified Theileria spp. and T. equi. Significantly, our findings revealed coinfection with Anaplasma spp., Theileria spp., and Babesia spp. While blood samples from wildlife were not specifically collected to assess infection in this study, the data on the presence of various pathogens in ticks observed can serve as valuable indicators to assess the health status of wildlife populations and to monitor disease dynamics. The findings could be valuable in developing programs for the treatment, prevention, and control of tick-borne illnesses in this area. However, additional research is required to determine the ticks' ability to transmit these pathogens and enhance the current understanding of the relationship among pathogens, ticks, and hosts. [ABSTRACT FROM AUTHOR]

Duck Tembusu virus (DTMUV) is an important flavivirus that can be transmitted to poultry via Aedes albopictus bites. Furthermore, humans residing in the DTMUV epidemic area display activated antiviral immune responses to local DTMUV isolates during the pathogenic invasion, thereby raising the primary concern that this flavivirus may be transmitted to humans via mosquito bites. Therefore, we identified the gene AALF004421, which is a homolog of the 34-kDa salivary protein (34 kDa) of Ae. albopictus and studied the salivary protein-mediated enhancement of DTMUV infection in Ae. albopictus salivary glands. We observed that double-stranded RNA-mediated silencing of the 34 kDa in mosquito salivary glands demonstrated that the silenced 34 kDa impaired DTMUV infectivity, similar to inhibition through serine protease. This impairment occurred as a consequence of triggering the innate immune response function of a macroglobulin complement-related factor (MCR). 34-kDa in the salivary gland which had similar activity as a serine protease, results in the abrogation of antimicrobial peptides production and strong enhance DTMUV replication and transmission. Although the function of the 34 kDa in Ae. albopictus is currently unknown; in the present study, we showed that it may have a major role in DTMUV infection in mosquito salivary glands through the suppression of the antiviral immune response in the earliest stages of infection. This finding provides the first identification of a prominently expressed 34 kDa protein in Ae. albopictus saliva that could serve as a target for controlling DTMUV replication in mosquito vectors. [ABSTRACT FROM AUTHOR]

The study of bacterial zoonoses has been under‐pursued despite the fact that bacteria cause the majority of zoonotic diseases, of which 70% have a wildlife origin. More Bartonella species are being identified as the cause of human diseases, and several of them have been linked to domestic and wild animals. Bats are outstanding reservoirs for Bartonella species because of their wide distribution, mobility, roosting behaviour, and long life span. Here, we carried out a PCR‐based survey on bats that were collected from 19 sampling sites in eight provinces of Thailand from February 2018 to April 2021. Bartonella infection was investigated in a total of 459 bats that belong to 24 different bat species (21 species of which had never been previously studied in Thailand). PCR diagnostics revealed that 115 out of 459 (25.5%) blood samples tested positive for Bartonella. The nucleotide identities of the Bartonella 16S rRNA sequences in this study were between 95.78‐99.66% identical to those of known zoonotic species (Bartonella ancashensis, Bartonella henselae, Bartonella bacilliformis and Bartonella australis) as well as to an unidentified Bartonella spp. In addition, the citrate synthase (gltA) and RNA polymerase‐beta subunit (rpoB) genes of Bartonella were sequenced and analyzed in positive samples. The gltA and rpoB gene sequences from Hipposideros gentilis and Rhinolophus coelophyllus bat samples showed low nucleotide identity (<95%) compared to those of the currently deposited sequences in the GenBank database, indicating the possibility of new Bartonella species. The phylogenetic inference and genetic diversity were generated and indicated a close relationship with other Bartonella species previously discovered in Asian bats. Overall, the current study demonstrates the primary evidence pointing to a potential novel Bartonella species in bats. This discovery also contributes to our current understanding of the geographical distribution, genetic diversity, and host ranges of bat‐related Bartonella. [ABSTRACT FROM AUTHOR]