(1) Background: Online health communities (OHCs) serve as ecosystems connecting doctors, patients, and medical resources. Studying their deep network structure and impact mechanisms on medical service quality provides a comprehensive understanding of digital healthcare ecosystems and has guiding significance for platform service optimization. (2) Methods: Using the “Good Doctor Online” platform as the data source, we employed social network analysis methods to construct network models from the professional title and disease-type dimensions, and used multiple linear regression statistical analysis to identify the influencing factors of doctor recommendation rates. (3) Results: Our analysis found that depression doctors exhibit the highest network connectivity (average degree = 17.378), and chief physicians demonstrate significantly higher internal connectivity (average degree = 9.353) compared to resident physicians (average degree = 0.804). The doctor recommendation rate is significantly correlated with post-consultation evaluation (r = 0.602, p < 0.001) and shows a 45% variance explanation (R² = 0.450) in our regression model. (4) Conclusions: Different disease types in OHCs demonstrate distinct organizational patterns, with depression networks showing significantly denser connections than diabetes networks. Professional titles strongly influence network position, with chief physicians forming highly connected hubs while resident physicians remain peripheral. Recommendation rates emerge through multi-dimensional trust processes primarily driven by post-consultation evaluation quality.

Objectives: To investigate associations between varicella vaccination and self-reported contact history with varicella or herpes zoster among clinically diagnosed varicella cases in Chaoyang District, Beijing, China. Methods: A retrospective observational study was conducted among 4441 clinically diagnosed varicella cases reported from 2017 to 2025. Multivariable logistic regression examined associations between vaccination status, number of doses, time since vaccination, and reported contact history with varicella and/or herpes zoster, adjusting for age, sex, and year of diagnosis. Results: Vaccinated cases had significantly higher odds of reporting contact with varicella or zoster compared with unvaccinated cases (OR = 1.34, 95% CI: 1.14–1.58). Both 1-dose and 2-dose recipients showed similar associations. A gradient of increasing odds was observed with longer time since vaccination, reaching OR = 3.17 (95% CI: 1.39–7.22) for 10 or more years since last dose. Associations were primarily driven by reported varicella contact rather than herpes zoster contact. Sensitivity analysis confirmed robustness of findings. Conclusions: Varicella vaccination was positively associated with reporting an identifiable exposure source. Vaccination status may influence completeness of exposure ascertainment in varicella surveillance and should be considered when interpreting contact tracing data.