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.