The tropical climate of the Philippines and the high population of dogs, particularly in cities, favors the life-cycle of the brown dog tick, Rhipicephalus sanguineus (sensu lato), a vector of several canine tick-borne pathogens (TBPs) including zoonotic Rickettsia spp. Suspected cases of infections are commonly encountered in veterinary clinics, but the specific TBPs are rarely identified. Furthermore, infection with Rickettsia is not being clinically examined in dogs. In this study, the occurrence of TBPs in blood and ticks collected from household and impounded dogs in highly populated areas of the Philippines, Metro Manila, and the nearby province of Laguna, was examined. A total of 248 blood samples and 157 tick samples were subjected to PCR. First, samples were screened using primers for Anaplasma/Ehrlichia spp. and Babesia/Hepatozoon spp. Those that turned positive were further subjected to species-specific PCR. Rickettsia spp. were also detected through a nested PCR. Of the 248 blood samples, 56 (22.6%) were positive for Anaplasma/Ehrlichia spp., while 19 (7.6%) were positive for Babesia/Hepatozoon spp. Species-specific PCR revealed that 61 (23.4%) had a single TBP, with Ehrlichia canis being detected in 39 (15.7%) dogs, while 14 (5.6%) dogs were positive for different combinations of two to four TBPs. Rickettsia infection was detected in 6 (2.4%) dogs. In tick samples, 8 (3.2%) were positive for Ehrlichia/Anaplasma spp., while only 1 (0.63%) was positive for Babesia/Hepatozoon spp. As in the blood samples, E. canis was the most detected, being found in 5 (2%) samples. No tick samples tested positive for Rickettsia spp. Ehrlichia canis is the most common TBP affecting dogs in the Philippines. Co-infection with TBPs is quite common, hence testing for multiple TBPs is necessary. Through nested PCR, Rickettsia infection was detected in dogs, and to the authors’ knowledge, this study provides the first molecular evidence of Rickettsia infection in dogs in the Philippines.

We isolated two highly pathogenic avian influenza viruses (HPAIVs) of subtype H5N8 clade 2.3.4.4b from falcated duck (Anas falcata) feces and environmental water collected at an overwintering site in Japan. Our isolates were almost genetically identical to each other and showed high genetic similarity with H5N8 HPAIVs recently isolated in South Korea, a distant part of Japan, and European countries. These results suggest the potential role of falcated ducks in the dissemination of HPAIVs.

Tick-borne diseases (TBDs) indulge in severe economic losses in the livestock industry by adversely affecting the small ruminant breeding in tropical and subtropical zone countries, including Turkey. Turkey encompasses a wide land area representing diverse climatic conditions. The present study explored the presence and distribution of Babesia ovis, Theileria ovis, Theileria lestoquardi, Anaplasma ovis, Anaplasma phagocytophilum and the co-occurrence status of these pathogens. A total of 299 sheep blood samples were collected from fifteen provinces located in six different geographical regions in Turkey. PCR analyses were executed using species-specific primers based on Babesia ovis BoSSU rRNA, Theileria ovis ToSSU rRNA, Theileria lestoquardi 18S rRNA, Anaplasma ovis Major Surface Protein (AoMSP4), and Anaplasma phagocytophilum 16S rRNA genes. Overall, 219 (73.24%) sheep were found to be infected with at least one of the following protozoan and rickettsial pathogens; B. ovis, A. ovis,T. ovis, and A. phagocytophilum. Theileria lestoquardi was not detected in any blood sample. The global prevalence of B. ovis, A. ovis, T. ovis, and A. phagocytophilum was estimated to be 2.68%, 16.05%, 41.47%, and 57.19%, respectively. Besides this, dual (24.41%), triple (9.03%), and quadruple (0.67%) co-infections were detected in the study. Phylogenetic analysis revealed significant nucleotide sequence identities between the sequences obtained in this study and the sequences registered in the GenBank. This study provides relevant data regarding the predominance of ovine tick-borne protozoan and rickettsial agents in Turkey. A high molecular prevalence of tick-borne pathogens (TBPs) was identified in the study. This situation indicates that TBPs should be screened continuously, and necessary control measures should be taken to prevent diseases caused by tick-borne protozoan and rickettsial agents.

Rabies virus phosphoprotein (P protein) is a multifunctional protein that plays key roles in replication as the polymerase cofactor that binds to the complex of viral genomic RNA and the nucleoprotein (N protein), and in evading the innate immune response by binding to STAT transcription factors. These interactions are mediated by the C-terminal domain of P (P_CTD). The colocation of these binding sites in the small globular P_CTD raises the question of how these interactions underlying replication and immune evasion, central to viral infection, are coordinated and, potentially, coregulated. While direct data on the binding interface of the P_CTD for STAT1 is available, the lack of direct structural data on the sites that bind N protein limits our understanding of this interaction hub. The P_CTD was proposed to bind via two sites to a flexible loop of N protein (N_pep) that is not visible in crystal structures, but no direct analysis of this interaction has been reported. Here we use Nuclear Magnetic Resonance, and molecular modelling to show N protein residues, Leu381, Asp383, Asp384 and phosphor-Ser389, are likely to bind to a ‘positive patch’ of the P_CTD formed by Lys211, Lys214 and Arg260. Furthermore, in contrast to previous predictions we identify a single site of interaction on the P_CTD by this N_pep. Intriguingly, this site is proximal to the defined STAT1 binding site that includes Ile201 to Phe209. However, cell-based assays indicate that STAT1 and N protein do not compete for P protein. Thus, it appears that interactions critical to replication and immune evasion can occur simultaneously with the same molecules of P protein so that the binding of P protein to activated STAT1 can potentially occur without interrupting interactions involved in replication. These data suggest that replication complexes might be directly involved in STAT1 antagonism.