Factors associated with timely vaccination of pertussis-containing vaccines in children born from 2019 to 2023, Shanghai

This study, led by Prof. Jing Li from Sichuan University and Prof. Dan Wu from Nanjing Medical University, was published in PLOS Medicine. Conducted in four community health centers in Chengdu, western China, this randomized controlled trial evaluated the impact of a “pay-it-forward” intervention on HPV vaccination among girls aged 15–18 years. Participants in the intervention arm received a community subsidy for their first HPV vaccine dose and were invited to donate and write encouragement postcards for future recipients, while the control arm self-paid at market price. The pay-it-forward approach increased first-dose uptake from 17.5% to 34.2%, significantly reduced vaccination delay, and enhanced vaccine confidence. Most families in the intervention arm engaged in donations and message sharing, and the cost per person vaccinated was lower than in the control group. Findings suggest that this community-engaged, reciprocity-based model is an effective and sustainable strategy to improve HPV vaccination coverage among catch-up age girls, with potential for broader implementation.

This study from Fudan University School of Public Health and the Shanghai CDC, published in Human Vaccines & Immunotherapeutics, leveraged the city’s immunization registry to conduct a retrospective cohort analysis of children born between September 1, 2018 and August 30, 2023. Children were classified by the COVID-19 phase at their expected vaccination dates (pre/post-epidemic, baseline, epidemic). Three pertussis-containing vaccines were included, namely, DTP, DTP-Hib, and DTP-IPV-Hib. Kaplan–Meier estimators and multivariable Cox models showed marked declines in timeliness when vaccination windows coincided with epidemic phases—for example, at 2 months the probability of timely vaccination was 0.89 (95% CI 0.86–0.92) during baseline vs 0.53 (95% CI:0.51–0.55) during epidemic periods; hazard ratios for timely vaccination at 3 and 5 months decreased by 12% (HR=0.88, 95% CI:0.86–0.90) and 9% (HR=0.91, 95% CI:0.87–0.94) in baseline vs pre/post, and by 49% (HR=0.51, 95% CI:0.49–0.53) and 57% (HR=0.43, 95% CI:0.40–0.46) during epidemic periods. Findings underscore the need for targeted catch-up and service-continuity measures to mitigate disruptions to routine childhood immunization.

This study from the Beijing Center for Disease Prevention and Control and the Beijing Research Center for Respiratory Infectious Diseases was published in Vaccine. In 2022, 2,333 healthy children under five from four sites in Hainan Province yielded 737 pneumococcal isolates. Grouped by individual PCV13 vaccination status and regional coverage, analyses showed significantly lower carriage of vaccine-type serotypes among vaccinated children (e.g., 6B: 7.0% vs 2.7%, P<0.01; 6A: 4.2% vs 1.2%, P<0.05; 23F: 2.2% vs 0.3%, P<0.05). Overall Spn non-susceptibility was high to erythromycin (92.3%), azithromycin (87.5%), clindamycin (81.2%), tetracycline (91.2%), penicillin (38.9%), and cefuroxime (64.7%), with 82.9% of isolates being multidrug-resistant (notably 92.4% among vaccine-type strains). Isolates from high-coverage areas exhibited lower resistance and MDR than those from low-coverage areas, indicating that expanding PCV13 coverage could reduce vaccine-type carriage and the community resistance burden.