Ticks and tick-borne pathogens significantly threaten human and animal health worldwide. Haemaphysalis longicornis is one of the dominant tick species in East Asia, including China. In the present study, 646 Ha. longicornis ticks were collected from free-ranging domestic sheep in the southern region of Hebei Province, China. Tick-borne pathogens of zoonotic and veterinary importance (i.e., Rickettsia, Anaplasma, Ehrlichia, Borrelia, Theileria, and Hepatozoon spp.) were detected in the ticks using PCR assays and sequence analysis. The prevalence rates of these pathogens were 5.1% (33/646), 15.9% (103/646), 1.2% (8/646), 17.0% (110/646), 0.15% (1/646), and 0.15% (1/646), respectively. For Rickettsia spp., R. japonica (n = 13), R. raoultii (n = 6), and Candidatus R. jingxinensis (n = 14) were detected for the first time in the province, while several Anaplasma spp. were also detected in the ticks, including A. bovis (n = 52), A. ovis (n = 31), A. phagocytophilum (n = 10), and A. capra (n = 10). A putative novel Ehrlichia spp. was also found with a prevalence of 1.2% in the area. The present study provides important data for effectively controlling ticks and tick-borne diseases in the Hebei Province region of China.

The reported cases of scrub typhus (ST) have continued to escalate, with outbreaks occurring regionally in China. These pose an increasing public health threat at a time when public health has been overwhelmed. During the period from July to August 2022, in Rongjiang County, Guizhou Province, China, 13 out of 21 fever patients were diagnosed with scrub typhus, based on epidemiological investigation and blood test analysis. The major clinical symptoms of these patients showed fever, chills, headache, eschar, fatigue and pneumonia, which were accompanied by a rise in C-reactive protein, neutrophils, alanine transaminase (ALT) and aspartate aminotransferase (AST). Furthermore, nearly half of them exhibited abnormal electrocardiogram activity. Through semi-nested PCR, Sanger sequencing and phylogenetic tree construction, the Karp strain ofOrientia tsutsugamushi(O.tsutsugamushi) was confirmed as the pathogen causing ST in Rongjiang County, which shared the same evolutionary branch withO.tsutsugamushiisolated from wild mouse liver or spleen, indicating that the wild mouse plays an important role in transmitting the disease. In contrast to the sporadic cases in the past, our study is the first to disclose an epidemic and the corresponding clinical characteristics of ST in Guizhou province, which is of great significance for the prevention and treatment of regional illnesses.

Rickettsia, Anaplasma, and Ehrlichia species are emerging tick-borne pathogens that cause zoonotic diseases, including rickettsiosis, anaplasmosis, and ehrlichiosis in both human and animal populations. This study aimed to investigate the prevalence of these pathogens in cattle-associated ticks from Ganzhou City, Jiangxi Province, China. Through molecular characterization using multilocus sequence analysis (16S rRNA, gltA, groEL, and ompA genes), we analyzed 392 Rhipicephalus microplus ticks collected from March to September in 2022. The PCR results showed that eight Rickettsiales bacteria were detected, including two species of Rickettsia (51/392, 13.0%), four species of Anaplasma (52/392, 13.3%), and two species of Ehrlichia (70/392, 17.9%). Notably, the circulation of multiple pathogen species within R. microplus populations demonstrates significant microbial diversity in this region. Further consideration and investigation should be given to the possible occurrence of rickettsiosis, ehrlichiosis, and anaplasmosis in humans and domestic animals. Our study provides critical baseline data for developing targeted surveillance strategies and informing public health interventions against tick-borne diseases in southeastern China.

Rickettsia, Anaplasma, and Ehrlichia species are emerging tick-borne pathogens that cause zoonotic diseases including rickettsiosis, anaplasmosis, and ehrlichiosis in both human and animal populations. This study aimed to investigate the prevalence of these pathogens in cattle-associated ticks from Ganzhou City, Jiangxi Province, China. Through molecular characterization using multilocus sequence analysis (16S rRNA, gltA, groEL, and ompA genes), we analyzed 392 Rhipicephalus microplus ticks collected from 2022 to 2023. The PCR results showed that 8 pathogens were detected, including 2 species of Rickettsia (51/392, 13.0%), 4 species of Anaplasma (52/392, 13.3%), and 2 species of Ehrlichia (70/392, 17.9%). Notably, the circulation of multiple pathogen species within R. microplus populations demonstrates significant microbial diversity in this region. Further consideration and investigation should be given to the possible occurrence of rickettsiosis, ehrlichiosis and anaplasmosis in humans and domestic animals. Our study provides critical baseline data for developing targeted surveillance strategies and informs public health interventions against tick-borne diseases in southeastern China.

Rickettsia conorii Indian tick typhus strain (R. conorii subsp. indica, ITTR) was detected in both a human patient and an attached Rhipicephalus turanicus tick that was removed from the patient in Yanqi County, Xinjiang Uygur Autonomous Region (XUAR), China. The molecular identification of the pathogen, along with previous reports, suggests it may be distributed across the area. A 55-year-old female farmer presented with fever, headache, eschar, and a maculopapular rash following a tick bite. Laboratory findings indicated thrombocytopenia, liver enzyme elevation, and proteinuria, which, combined with clinical symptoms, strongly suggested a rickettsial infection. PCR and sequencing of multiple rickettsial genes confirmed the presence of ITTR in both the patient and the tick. Furthermore, the genetic identity between these sequences provided evidence that R. turanicus can act as a vector of ITTR. This case provides valuable insights into the clinical manifestation, diagnosis, and treatment of ITTR infections. These findings highlight the need for improved surveillance and awareness of tick-borne rickettsial diseases in regions with high tick exposure.

Chlamydia pecorum is a widespread zoonotic pathogen infecting livestock and wildlife, with recent reports of severe human infection. To assess its epidemiological threat, we investigated its prevalence, genetic diversity, and evolutionary dynamics in livestock from western China. Rectal swabs (n = 1322) were collected from cattle and sheep across four provinces in western China in 2024–2025. Samples were screened by Nested PCR, and positives were characterized by ompA genotyping and multilocus sequence typing (MLST). Overall, 18.9% of samples tested positive for C. pecorum. ompA analysis defined 33 sequence similarity-based clades (17 unique to the region), while MLST revealed 114 sequence types (111 novel). Discordance between ompA and MLST trees highlighted recombination and complex evolutionary trajectories. These findings demonstrate both a high prevalence and marked genetic heterogeneity of C. pecorum in western Chinese livestock, with numerous unique local clades and sequence types highlighting its ongoing evolution and zoonotic potential. Therefore, this study provides a foundational genetic database and has prompted the creation of a One Health surveillance network, which are essential for precise source-tracing and early detection to mitigate zoonotic spillover risk.