Background Enterovirus 71 (EV71) infection contributes to hand, foot, and mouth disease (HFMD) with severe neurogenic complications, leading to higher morbidity. In addition to their typical roles in coagulation, platelets could serve as essential immune regulatory cells to play a key role in the pathogenesis of this viral infection. Methods Platelet parameters were measured using an automatic hematology analyzer. T-helper type 1 (Th1) and Th2 cells were analyzed by flow cytometry. The levels of cytokines and key transcription factors were determined. Results The levels of platelet count and plateletcrit were positively associated with the severity of HFMD. Th1 and Th2 cells as well as their corresponding cytokines were increased in the severe group compared to the healthy volunteers. Moreover, the levels of platelets were negatively correlated with the level of interferon-γ (IFN-γ), but positively correlated with the frequency of Th1 cells. Coculture of platelets and naive CD4⁺ T cells showed that platelets from mild patients promote Th1 cell differentiation and IFN-γ secretion. Conclusions Our study has shown for the first time that the distinct roles of platelets are responsible for the regulation of pathogenic CD4⁺ T cell differentiation and function in the pathogenesis of HFMD caused by EV71. Impact Our study has shown for the first time that the distinct roles of platelets are responsible for the regulation of pathogenic CD4⁺ T cell differentiation and function in the pathogenesis of HFMD caused by EV71. For the first time, we have discovered the role of platelets in children’s HFMD caused by EV71 infection, which may provide a better treatment for HFMD in the future. This article describes new discoveries in platelet immunity.

Background: Information on the intention of parents of children with special diseases to vaccinate their children against coronavirus disease 2019 (COVID-19) is scarce.Methods: In this survey, all participants (n = 914) were enrolled from a tertiary children's hospital between September 2020 and April 2021. A face-to-face questionnaire interview was conducted to collect information on the special diseases of children and parental attitudes about the COVID-19 vaccine. We compared the demographic and disease factors between the group of parents who were willing to vaccinate their children against COVID-19 and the group who were unwilling to vaccinate.Results: Among 941 children, 58.1% (n = 547) were boys. The Mean age was 1.4 (SD 1.9) years. If the COVID-19 vaccine becomes available for the child, 470 (49.9%) of parents were willing to provide vaccination for their children. The less the education levels of the father or mother, the more likely they were to vaccinate their children (P = 0.003, P = 0.007). However, more intentions to vaccinate were provided in parents of children with COVID-19 prevention and control education (P < 0.001).Conclusion: Our findings provided evidence that some parents are willing to vaccinate their children with special diseases against COVID-19. Professional knowledge about COVID-19 prevention and control may contribute to increased parental intention.

Lyme disease, caused by Borrelia burgdorferi and transmitted by blacklegged ticks (Ixodes species), is the most common vector-borne disease in the United States. Its spatiotemporal dynamics are influenced by environmental and socioeconomic factors, yet the impacts of the COVID-19 pandemic on Lyme disease remain unclear. We analyzed county-level Lyme disease surveillance data (2001−2022) alongside environmental, socioeconomic, and tick vector data. Using machine learning models (Random Forest, Boosted Regression Trees, and XGBoost) and Shapley Additive Explanations (SHAP), we evaluated the influence of key predictors on Lyme disease risk. Predicted cases for 2020–2022 were compared with actual reports to assess the pandemic's effects. Lyme disease cases rose from 16,862 in 2001 to 61,802 in 2022, with geographic expansion into southeastern regions. Population density, ecological niche of I. scapularis, and maximum temperature were presented as the key predictors of disease risk. The COVID-19 pandemic severely disrupted reporting dynamics, with 2020 and 2021 cases falling 43.9 % (95 % CI: 41.2–46.7 %) and 22.0 % (95 % CI: 19.5–24.5 %) below predictions, respectively—a decline most pronounced in the Northeast and linked to reduced healthcare access and outdoor activity during lockdowns. Our findings highlight the complex interactions of environmental, socioeconomic, and behavioral factors in Lyme disease dynamics, including the significant impact of the COVID-19 pandemic on disease reporting. These insights underscore the need for integrated, data-driven public health strategies to mitigate Lyme disease risk in the United States.

Purpose: The Chinese government has authorized the emergency use of an inactivated vaccine for COVID-19 in children and adolescents aged 3 to 17 years. This study aimed to investigate parents’ attitudes towards vaccinating their children against COVID-19 and influencing factors. Patients and Methods: Through an online questionnaire survey, we collected self-reported children’s demographic characteristics, physical conditions and parents’ attitudes towards COVID-19 vaccination for children. The parents in the unwilling group received online consultation about the benefits and risks of COVID-19 vaccine and were asked to complete the questionnaire again. Results: A total of 868 participants were recruited from July 2021 to August 2021 in Nanjing, China. Overall, 76.0% of parents were willing to accept vaccination for children. Parents’ willingness increased with children’s age (P=0.018) and height (P=0.034), but decreased if the children fell sick within previous one month (P=0.030). Most of the unwilling parents gave a higher score to the risk of vaccination (53.76 VS 40.18). Unsafety (63.8%) and unfamiliarity (24.0%) were their major concerns. After consultation with a health worker, 24% of the unwilling parents turned willing. Conclusion: Children’s age and recent physical condition are related to parents’ attitudes towards vaccination for children against COVID-19. The major concerns of parents are unsafety and unfamiliarity. Parents view health workers as a reliable source of vaccine information. A successful consultation with health workers to understand the benefits and risks of vaccination can increase parents’ willingness. This study provides insight into parents’ attitudes towards vaccination for children against COVID-19 in China and related influencing factors. Our findings could be referenced in establishing policies for vaccinating children against COVID-19 in China.

Background: The HIV-1 molecular network is an innovative tool, using gene sequences to understand transmission attributes and complementing social and sexual network studies. While previous research focused on static network characteristics, recent studies’ emphasis on dynamic features enhances our understanding of real-time changes, offering insights for targeted interventions and efficient allocation of public health resources. Objective: This study aims to identify the dynamic changes occurring in HIV-1 molecular transmission networks and analyze the primary influencing factors driving the dynamics of HIV-1 molecular networks. Methods: We analyzed and compared the dynamic changes in the molecular network over a specific time period between the baseline and observed end point. The primary factors influencing the dynamic changes in the HIV-1 molecular network were identified through univariate analysis and multivariate analysis. Results: A total of 955 HIV-1 polymerase fragments were successfully amplified from 1013 specimens; CRF01_AE and CRF07_BC were the predominant subtypes, accounting for 40.8% (n=390) and 33.6% (n=321) of the specimens, respectively. Through the analysis and comparison of the basic and terminal molecular networks, it was discovered that 144 sequences constituted static molecular networks, and 487 sequences contributed to the formation of dynamic molecular networks. The findings of the multivariate analysis indicated that the factors occupation as a student, floating population, Han ethnicity, engagement in occasional or multiple sexual partnerships, participation in anal sex, and being single were independent risk factors for the dynamic changes observed in the HIV-1 molecular network, and the odds ratio (OR; 95% CIs) values were 2.63 (1.54-4.47), 1.83 (1.17-2.84), 2.91 (1.09-7.79), 1.75 (1.06-2.90), 4.12 (2.48-6.87), 5.58 (2.43-12.80), and 2.10 (1.25-3.54), respectively. Heterosexuality and homosexuality seem to exhibit protective effects when compared to bisexuality, with OR values of 0.12 (95% CI 0.05-0.32) and 0.26 (95% CI 0.11-0.64), respectively. Additionally, the National Eight-Item score and sex education experience were also identified as protective factors against dynamic changes in the HIV-1 molecular network, with OR values of 0.12 (95% CI 0.05-0.32) and 0.26 (95% CI 0.11-0.64), respectively. Conclusions: The HIV-1 molecular network analysis showed 144 sequences in static networks and 487 in dynamic networks. Multivariate analysis revealed that occupation as a student, floating population, Han ethnicity, and risky sexual behavior were independent risk factors for dynamic changes, while heterosexuality and homosexuality were protective compared to bisexuality. A higher National Eight-Item score and sex education experience were also protective factors. The identification of HIV dynamic molecular networks has provided valuable insights into the characteristics of individuals undergoing dynamic alterations. These findings contribute to a better understanding of HIV-1 transmission dynamics and could inform targeted prevention strategies.