Molecular-phylogenetic analyses of Babesia and Theileria species from small mammals and their ticks in northern China suggest new reservoirs of bovine and equine piroplasms.

Babesia and Theileria species (Apicomplexa: Piroplasmida) are tick-borne protozoan parasites that can cause mild to severe infection in humans, wildlife, livestock and companion animals. To date, reports on the molecular study of piroplasms from wild living small mammals and their ticks are still limited, especially in Asia. This study encompassed an extensive survey involving 907 liver samples and 145 ixodid ticks from 16 different species of small mammals (Rodentia, Lagomorpha, Eulipotyphla). These were collected in 13 cities and counties in northern China. DNA extracts from these samples were screened for the presence of piroplasm 18S rRNA gene. Samples that tested positive were further evaluated for other genetic markers of piroplasms, including the cox1 gene and the ITS1-5.8S rDNA-ITS2 region. Several piroplasm species were identified, including Babesia sp. tavsan2, Babesia occultans, Theileria sp. Xinjiang, Theileria equi, and Theileria sp. Kalecik. Among these, Theileria sp. Xinjiang was shown to be the most prevalent. Importantly, Babesia sp. tavsan2 was identified in the tick Rhipicephalus sanguineus from the Yarkand hare and Theileria sp. Kalecik in Hyalomma asiaticum from the long-eared hedgehog, in line with the detection of these pathogens in tissue samples of the relevant hosts. This study further disclosed the presence of DNA from B. occultans and T. equi, typically found in cattle and horses respectively, with an additional discovery in small mammals. Moreover, Theileria sp. Kalecik, which was first detected in small-sized mammals, and Babesia sp. tavsan2, were both reported for the first time in China.

First Molecular Evidence of Babesia caballi and Theileria equi in Imported Donkeys from Kyrgyzstan.

Equine piroplasmosis (EP) is an important tick-borne disease of equids, caused by Theileria equi, Theileria haneyi, and Babesia caballi. Nonetheless, there has been a scarcity of systematic reports on EP parasites in donkeys in Kyrgyzstan, Central Asia. In this study, piroplasms were screened in 1900 blood samples from imported donkeys from the Osh Oblast (southwestern Kyrgyzstan) by targeting partial 18S ribosomal RNA using the polymerase chain reaction (PCR). Through molecular and phylogenetic analyses, all positive samples were sequenced to identify the species and genotypes. The results indicated the presence of both B. caballi and T. equi, with prevalence rates of 8.4% (160/1900) and 12.2% (232/1900), respectively. By amplifying part of the Erythrocyte Merozoite Antigen 1 (EMA-1) and Rhoptry-Associated Protein (RAP-1) genes, B. caballi genotype B and T. equi genotype A were identified. To the best of our knowledge, this is the first report on piroplasm infection among donkeys from Kyrgyzstan.

Clinical and historical infection of Tacheng tick virus 2: A retrospective investigation.

BACKGROUND: Tacheng tick virus 2 (TcTV-2) is an emerging tick-borne virus belonging to the genus Uukuvirus in the family Phenuiviridae. Initially isolated in 2019 from a patient in Xinjiang Uygur Autonomous Region (XUAR), northwestern China, who developed fever and headache after a tick bite, TcTV-2 was concurrently molecularly detected in hard ticks across various countries, including China, Kazakhstan, Romania, and Turkey. This study conducted a retrospective epidemiological investigation of TcTV-2 infection. METHODOLOGY: In this retrospective cohort study, we collected samples from 47 tick-bitten patients, 984 herdsmen, 7 Asian badgers, 13 red foxes, and 168 Hyalomma asiaticum tick egg batches. Patients' samples were primarily analyzed by using high-throughput sequencing, targeting the V3-V4 region of the bacterial 16S rRNA gene and viral cDNA libraries. Typical tick-borne pathogens were further confirmed using RT-PCR and detected in Asian badgers, red foxes and Hy. asiaticum tick egg batches. We also conducted enzyme-linked immunosorbent assay (ELISA) to detected specific IgM and IgG antibodies against TcTV-2 in herdsmen. Phylogenetic analysis was performed to genetically characterize TcTV-2 detected in this study. PRINCIPAL FINDINGS: TcTV-2 was detected in various samples, including blood, urine, and throat swabs from 12.77% (6/47) tick-bitten patients. It was found in blood samples of 14.29% (1/7) of wild badgers, 7.69% (1/13) of red foxes, and 13.69% (23/168) of Hy. asiaticum egg batches. Furthermore, ELISA results revealed that 9.55% (94/984) of the serum samples (34 from males and 60 from females) were tested positive for TcTV-2-specific IgG, while 2.95% (29/984, 7 males and 22 females) showed positivity for TcTV-2-specific IgM. Additionally, 1.02% (10/984, 4 males and 6 females) of the sera tested positive for both TcTV-2-specific IgM and IgG. Phylogenetic analysis indicated that the TcTV-2 strains detected in this study were genetically similar, regardless of their origin and host species. CONCLUSIONS: Clinical symptoms of TcTV-2 infection in patients are nonspecific, with common symptoms including headache, fever, asthenia, vomiting, myalgia, rash, and meningitis-like signs. TcTV-2 can be detected in blood, urine, and throat swab samples of infected patients. Among local herdsmen, 9.55% tested positive for TcTV-2-specific IgG and 2.95% for TcTV-2-specific IgM. Importantly, TcTV-2 can be transovarially transmitted in Hy. asiaticum ticks, and the Asian badgers and red foxes are potential reservoirs of TcTV-2.

Detection of patients with methamphetamine dependence with cue-elicited heart rate variability in a virtual social environment.

In the present study, we developed a methamphetamine (METH)-related virtual social environment to elicit subjective craving and physiological reactivity. Sixty-one male patients who were abstinent from METH use and 45 age-matched healthy males (i.e., normal controls) were recruited. The physiological electrocardiogram (ECG) signals were recorded before (resting-state condition) and during viewing of a METH-cue video in the virtual environment (cue-induced condition). The cue-induced subjective craving was measured with a visual analogue scale (VAS) for patients with METH dependence. The results indicated that the cue-induced condition elicited significant differences in heart rate variability (HRV) between patients with METH dependence and normal controls. The changes of HRV indexes on time domain and non-linear domain from the resting-state condition to the cue-induced condition were positively correlated with the score on VAS of METH craving. Using a supervised machine learning algorithm with the features extracted from HRV changes, our results showed that the discriminant model provided a high predictive power for distinguishing patients with METH dependence from normal controls. Our findings support that immersing subjects with METH dependence in a METH-related virtual social environment can successfully induce physiological reactivity, and cue-induced physiological signal changes may have a potential implication in clinical practice.