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Background: In May 2024, a chickenpox outbreak was reported at Xiasha Primary School located in Nanshan District, Shenzhen City, China, with a total of 12 cases identified. Despite thorough on-site investigations, the source of infection remained undetected. The purpose of our study was to infer the timing and duration of the infectious period of the initial case using modeling techniques, thereby deducing the identity of the source., Methods: We conducted an individual contact survey within the class affected by the epidemic and utilized an agent-based model (ABM) to estimate the key parameters related to the timing of the infectious source's emergence and the duration of its infectiousness. The point estimates derived from the ABM served as prior information for a subsequent Bayesian analysis, which in turn provided the posterior distribution for these parameters., Results: Our models suggested the infection source entered the classroom around April 24th (95% credible interval: April 22nd to April 26th), with an infectious period of approximately two days. Based on these findings, we should aim to detect students who may have been absent due to atypical chickenpox symptoms during this period and closely examine teachers who were present for two consecutive days for any indication of potential infection., Conclusion: This study demonstrates the efficacy of combining contact surveys with mathematical modeling for outbreak source tracing, offering a novel approach to supplement field epidemiological surveys., Clinical Trial Number: Not applicable., (© 2024. The Author(s).)

Background: This study aimed to analyze the relationship between health literacy and quality of life in patients with TB in Tibet and explore the mediating effects of self-efficacy and self-management in the relationship between health literacy and quality of life., Methods: We used a convenience sampling method to select 271 cases of patients with TB in Tibet to conduct a survey of their general information, health literacy, self-management, self-efficacy and quality of life, and to construct structural equation models., Results: The total health literacy score of patients with TB in Tibet was 84.28±18.57, while the lowest score was for information acquisition ability (55.99±25.66). Scores for quality of life were generally lower than the norm (patients with chronic diseases from other cities in China) (p<0.01). Moreover, self-efficacy and self-management mediated the relationship between health literacy and quality of life (p<0.05)., Conclusions: In Tibet, patients with TB have a low level of health literacy and an average level of quality of life. Emphasis should be placed on improving information access literacy, role-physicals and role-emotional to improve overall quality of life. The mediating roles of self-efficacy and self-management between health literacy and quality of life may provide a basis for further interventions., (© The Author(s) 2023. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene.)

Toxoplasma gondii is a protozoan with worldwide distribution that infects birds and mammals, including humans. The consumption of free-range chicken meat is a common practice in many parts of the world. However, little information is available concerning the molecular prevalence and genotypes of T. gondii infection in free-range chickens intended for human consumption in China. In this study, a total of 1360 serum samples were collected from food markets in Hunan province of China for detecting T. gondii antibodies by indirect hemagglutination assay. In addition, 650 brain tissues were also collected to investigate T. gondii DNA by amplification of B1 gene with a seminested polymerase chain reaction (PCR), and the positive DNA samples were typed at 10 genetic markers using multilocus PCR-restriction fragment length polymorphism. Antibodies to T. gondii were detected in 457 of the examined serum samples (33.6%; 95% confidence interval [CI]: 31.1-36.1), and 72 DNA samples (11.1%; 95% CI: 8.6-13.4) were positive for the T. gondii B1 gene. In this study, region and age of free-range chickens were shown to be risk factors for T. gondii infection ( p  < 0.01). Two genotypes (ToxoDB#9 and ToxoDB#52) were identified from two samples with complete genotyping results. Our study revealed a high prevalence of T. gondii infection in free-range chickens intended for human consumption in Hunan province, suggesting that recommendations to consumers should be made, especially in some regions of China where consumption of undercooked chicken meat is common. This is the first genetic characterization of T. gondii in free-range chickens intended for human consumption in Hunan province, China, and also the first report of genotype ToxoDB#52 in China.

Neospora caninum is a protozoan parasite which can infect many mammals and birds with a worldwide distribution. However, no molecular data are available about the occurrence of N. caninum in pigs. In this study, the serological and molecular prevalence of N. caninum infection in farmed pigs were investigated in Hunan province, China, between January 2017 and December 2018. A total of 1,500 serum samples collected from 10 herds in Hunan province were evaluated using a competitive-inhibition enzyme-linked immunoassay assay (cELISA). The overall seroprevalence of N. caninum in the examined pigs was 1.9%. The seroprevalence of N. caninum ranged from 0.3% to 4.6% among different regions in Hunan province of China (p < .05). DNA was extracted from brain samples, and the Nc-5 gene and ITS-1 region were amplified and then sequenced. Three (0.5%) of the examined 600 brain tissues were found to contain N. caninum DNA. Our phylogenetic analyses indicated that N. caninum samples were classified into two distinct groups. Although the prevalence is low within the pig groups investigated, our results revealed the emergence of N. caninum infection in pigs in China. The finding of the present study provides molecular evidence that the pigs are the natural intermediate host of N. caninum and may have major epidemiological importance., (© 2019 Blackwell Verlag GmbH.)

Background: Cryptosporidium viatorum is a minor Cryptosporidium pathogen in humans. Currently, there is limited information regarding the prevalence and genotypes of C. viatorum in animals in China., Methods: In this study, 228 faecal samples were collected from two wild rat species (Leopoldamys edwardsi and Berylmys bowersi) in Chongqing Municipality and Guangdong Province, China. These specimens were analyzed for C. viatorum and then subtyped it using PCR and sequence analysis of the small subunit ribosomal RNA (SSU rRNA) and 60-kilodalton glycoprotein (gp60) genes, respectively., Results: A total of 25 (11.0%) faecal samples were tested positive for C. viatorum by SSU rRNA assay. Of these samples, 4 (3.6%) came from L. edwardsi and 21 (18.0%) from B. bowersi. Of the 25 C. viatorum-positive samples, 17 were successfully amplified at the gp60 gene locus, which represented four subtypes belonging to two subtype families, including XVa (XVaA6, XVaA3g, XVaA3h) and XVc (XVcA2G1). Phylogenetic analysis based on the gp60 amino acid sequences indicated that all of the C. viatorum isolates grouped together, supporting the conclusion that C. viatorum from the wild rats represent two subtype families., Conclusions: These results indicate an occurrence of C. viatorum XVa subtype family from rats which is genetically identical to those found in humans. Our findings suggest that wild rats may be a potential source of human cryptosporidiosis.

Neospora caninum is an intracellular protozoan infecting many domestic and wild animals. In the present study, the brain tissues of wild birds collected in Hunan province of China were examined by N. caninum specific nested PCR, targeting the Nc-5 gene and the internal transcribed spacer 1 (ITS-1) region of the nuclear ribosomal DNA. The prevalence of N. caninum was detected in 15.5% (37/239) of wild birds, including 20.5% (9/44) of the examined olive-backed pipit Anthus hodgsoni, 18.3% (24/131) of the examined tree sparrows Passer montanus, 7.9% (3/38) of the examined chestnut bunting Emberiza rutila and 3.8% (1/26) of the examined yellow-breasted bunting E. aureola. Phylogenetic analyses showed that N. caninum from different hosts and geographical origins are genetically diverse and can be further classified into two distinct groups. Our findings indicated that wild birds are potential source of N. caninum for other animals. To our knowledge, this is the first report of N. caninum infection in wild birds in China, which provides a foundation for the prevention and control of this parasite in China and elsewhere., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Background: A tick-borne segmented RNA virus called Jingmen tick virus (JMTV) was recently identified, variants of which were detected in a non-human primate host and fatal patients with Crimean-Congo haemorrhagic fever. We investigated its infectivity and pathogenicity for humans., Methods: We obtained skin-biopsy, blood and serum samples from patients with tick bites, and used high-throughput sequencing, in situ hybridisation, and serologic testing to diagnose and ascertain the cases of JMTV infection., Findings: A JMTV strain was isolated from the tick Amblyomma javanense into an embryo-derived tick cell line. We obtained sustained passage of JMTV, and revealed that it was able to accumulate in salivary glands of experimentally infected ticks. Four JMTV-infected patients were identified by high-throughput sequencing of skin biopsies and blood samples. The virus replication in skin tissue was visualised by in situ hybridisation. The four patients all had an itchy or painful eschar at the site of tick bite, with or without lymphadenopathy. Immunohistochemical examination revealed remarkable local inflammation manifested as infiltration by neutrophils. Eight patients were identified by serological testing and showed more severe clinical manifestations. Two Ixodes persulcatus ticks detached from patients were positive for JMTV. All JMTV strains identified in this study formed a well-supported sub-lineage, distinct from those previously reported in China. Interpretation The public significance of JMTV should be highly concerning due to its potential pathogenicity for humans and efficient transmission by potential ticks. FUND: China Natural Science Foundation, State Key Research Development Programme, and United Kingdom Biotechnology and Biological Sciences Research Council., (Copyright © 2019 The Authors. Published by Elsevier B.V. All rights reserved.)