01
Analysis of Human Papillomavirus Vaccination Coverage Among Females Aged 9–45 Years in Shanghai, 2017–2024
This study, published in the Chinese Journal of Epidemiology, aimed to assess HPV vaccination uptake among women aged 9–45 years in Shanghai from 2017 to 2024, providing evidence to support the optimization of local immunization strategies. Using data extracted from the Shanghai Vaccination Integrated Management and Immunization Information System, the study collected monthly reports of administered HPV vaccine doses from all vaccination providers across the city. It estimated first-dose coverage and completion rates and further analyzed vaccination patterns across age groups, districts, and vaccine types.
The findings showed that a total of 5.8194 million HPV vaccine doses were administered to women in Shanghai between 2017 and 2024, of which 3.5854 million (61.61%) were 9-valent vaccines. Overall vaccination volume increased steadily over time, with a slight decline observed in 2024. By age group, women aged 20–24 years received the largest proportion of doses (22.05%). The 9–14, 15–19, 20–24, and 40–45 age groups showed a clear preference for the 9-valent vaccine, while women aged 25–39 years more frequently chose the 4-valent vaccine. The proportion of 9-valent vaccine use rose markedly across all age groups in 2023 and 2024.
Among all women aged 9–45 years in the city, the estimated first-dose coverage was 36.96%, and the overall series-completion rate reached 93.58%. The 9–14 age group had the lowest estimated first-dose coverage (14.10%) and the lowest completion rate (85.77%). Women aged 20–24 years had the highest estimated first-dose coverage (88.64%), while those aged 25–29 years had the highest completion rate (94.15%). Coverage also varied geographically: women living in urban districts had higher estimated first-dose coverage and completion rates (57.39% and 94.11%, respectively) than those in suburban areas.
The study highlights that, despite Shanghai’s HPV vaccination coverage exceeding the national average, it still lags behind levels observed in high-income countries, with notable gaps among females under 20 years of age.
DOI: 10.3760/cma.j.cn112338-20250319-00176
02
Immunogenicity comparison of an Escherichia coli-produced 9-valent human papillomavirus vaccine and Gardasil 9 in Chinese women aged 18–26 years: three-year follow-up data from a randomised clinical trial
This study, published in The Lancet Regional Health – Western Pacific, aimed to compare the plateau-phase antibody levels three years after the first dose between the domestically produced Escherichia coli–expressed 9-valent HPV vaccine (Cecolin®9) and the imported 9-valent vaccine (Gardasil®9) among Chinese women aged 18–26 years.
Previous research (NCT04782895) has demonstrated that, at month 7 (one month after completing the three-dose schedule), the type-specific immune responses induced by Cecolin9 were non-inferior to those induced by Gardasil 9 among Chinese women aged 18–26 years. The present study is a prospective extension of that randomized, single-blind clinical trial conducted in China (NCT06197802), inviting all participants from the primary study to return for follow-up.
Blood samples were collected three years after the first vaccination (median follow-up: 34 months). Type-specific serum neutralizing antibodies were measured using a tricolor pseudovirus-based neutralization assay. The primary endpoint was geometric mean concentration (GMC), evaluated in participants who completed all three doses, had no major protocol deviations, were seronegative for the corresponding HPV types at baseline, and provided valid serum samples at year three. Non-inferiority was defined as the lower bound of the two-sided 95% confidence interval (CI) of the GMC ratio (Cecolin 9 / Gardasil 9) exceeding 0.5.
Of the 487 participants enrolled in the primary study, 403 (82.8%) completed the three-year follow-up. The mean age at first vaccination was 22.2 years in the Cecolin9 group (n=200) and 22.1 years in the Gardasil 9 group (n=203). Across all nine HPV types, GMC ratios ranged from 0.78 (95% CI: 0.64–0.95) to 1.91 (95% CI: 1.54–2.37), with all lower bounds of the 95% CIs (0.64 to 1.54) exceeding the predefined non-inferiority margin of 0.5. Both vaccines also showed sustained and comparable seropositivity rates: 84.7%–100.0% for Cecolin9 and 86.2%–100.0% for Gardasil 9. Notably, the two groups exhibited consistent antibody waning patterns throughout the follow-up period.
The study concludes that the plateau-phase HPV type-specific antibody responses induced by Cecolin 9 at three years post-vaccination are non-inferior to those induced by Gardasil 9 among Chinese women aged 18–26 years, indicating comparable potential for long-term immune protection.
https://doi.org/10.1016/j.lanwpc.2025.101671
03
Efficacy, immunogenicity, and safety of pneumococcal conjugate vaccine in children: a systematic review and meta-analysis
This article, published in Frontiers in Pediatrics, aimed to evaluate the effects of pneumococcal conjugate vaccines (PCVs) on pneumonia incidence, immunogenicity, and safety among children aged 0–2 years. The review included randomized controlled trials published up to June 19, 2024, in which the intervention group received a PCV and the control group received a placebo. Eligible studies focused on children aged 0–2 years and reported outcomes including pneumonia incidence, serotype-specific immune responses, and adverse events.
A total of 11 studies involving 147,247 participants were included. Meta-analysis showed that children who received PCVs had a significantly lower risk of pneumonia compared with controls (RR = 0.78, 95% CI: 0.70–0.87, P < 0.001). Regarding immunogenicity, IgG geometric mean ratios (GMRs) for serotypes 6B, 9V, 14, 18C, 19F, and 23F increased significantly after vaccination, with GMRs of 22.16 (95% CI: 3.73–131.47; P < 0.001), 15.18 (95% CI: 1.48–155.27; P = 0.02), 12.50 (95% CI: 1.76–88.98; P = 0.01), 20.20 (95% CI: 1.47–276.72; P = 0.04), 15.43 (95% CI: 1.14–209.15; P = 0.04), and 13.74 (95% CI: 2.42–78.01; P = 0.003), respectively. No statistically significant increases were observed for serotypes 1, 4, or 5.
For safety outcomes, reporting across studies was inconsistent. Most trials documented local reactions and transient systemic symptoms as the most common adverse events. A few studies reported potential serious adverse events such as asthma; however, the overall evidence did not identify any widespread serious safety concerns.
The findings indicate that PCVs effectively reduce the risk of pneumonia and elicit strong serotype-specific immune responses for several key serotypes among young children. The current evidence supports incorporating PCVs into routine childhood immunization schedules. The authors suggest that future research should extend follow-up duration, include more diverse populations, adopt standardized adverse event reporting, and continue monitoring serotype replacement and antimicrobial resistance trends.
https://doi.org/10.3389/fped.2025.1652946
04
Vaccinations in preterm infants: Which and when?
This article, published in Seminars in Fetal and Neonatal Medicine, provides a comprehensive review of the safety, effectiveness, and timing of vaccinations for preterm infants. By integrating recommendations from Germany, the United States, and the World Health Organization (WHO), the study aims to establish an evidence-based immunization strategy tailored for this immunologically vulnerable population.
The review finds that rotavirus vaccines demonstrate good safety profiles in preterm infants and effectively prevent severe gastroenteritis. However, clinical audits show that the in-hospital vaccination rate is only about 30%, highlighting the need for more systematic management of inpatient vaccination procedures. For multivalent combination vaccines—such as the hexavalent diphtheria–tetanus–pertussis–polio–Haemophilus influenzae type b–hepatitis B vaccine—a “3+1” schedule is recommended, and extremely preterm infants should undergo at least 48 hours of vital-sign monitoring following the first dose. Pneumococcal conjugate vaccines can induce immune protection comparable to term infants once the full series is completed, and both meningococcal B and C vaccines show good tolerability. For live attenuated vaccines—such as the measles–mumps–rubella vaccine and the varicella vaccine—administration is recommended after 9 months of age. Influenza vaccines are advised from 6 months of age, while COVID-19 vaccines are reserved for preterm infants with underlying chronic conditions.
The study notes several immunological characteristics unique to preterm infants: reduced placental transfer of maternal antibodies, limited T-cell function (such as decreased interferon-γ production), reduced B-cell antibody diversity, and delayed gut microbiome development. These factors can all contribute to weaker vaccine responses compared with term infants. Future research is expected to focus on novel adjuvant development, optimization of maternal immunization strategies, application of mRNA vaccine platforms, and microbiome-targeted modulation to enhance vaccine responsiveness.
Current evidence underscores that preterm infants should be vaccinated strictly according to chronological age. Health systems should strengthen vaccination procedures, improve follow-up mechanisms, and enhance family health education to build an effective immunization shield for this high-risk population.
https://doi.org/10.1016/j.siny.2025.101670
05
Birth order and influenza vaccination: a comparative study of behaviors and intentions between first-time and second-time Chinese parents
This article, published in Expert Review of Vaccines, examines how birth order influences influenza vaccination behaviors and intentions among Chinese parents of children aged 0–6 years. The study aims to identify key factors contributing to vaccination disparities and provide evidence for targeted strategies that can reduce health inequities.
A nationwide cross-sectional survey was conducted in China between July and August 2024 using a stratified sampling approach. A total of 3,569 parents of children aged 0–6 years completed a questionnaire designed based on the World Health Organization’s Determinants of Vaccine Hesitancy Matrix (WHO-DVH Matrix). The study applied logistic regression to analyze the association between parental age and vaccine hesitancy/vaccination uptake, used a random forest algorithm to identify major predictors, and employed one-way ANOVA to test influencing factors.
The results show that 66.9% of participants were first-time parents, while 33.1% were parents with multiple children. Among children under 40 months of age, firstborns had significantly lower vaccination rates compared with later-born children (64.9% vs. 71.7%, p = 0.022). Before 49 months of age, first-time parents exhibited higher levels of vaccine hesitancy than experienced parents (58.6% vs. 49.9%, p < 0.001). However, these differences diminished gradually once children reached three years of age. The study further reveals that “influence of historical events” is the strongest predictor of vaccination intent among first-time parents, whereas “vaccination as a social norm” shows the highest predictive power for parents with multiple children. Other important predictors for first-time parents include trust in the health system and personal experience, social norms, and perceived reliability of vaccine supply. For parents with multiple children, the image of pharmaceutical companies and the reliability of vaccine supply also play important roles. Notably, “vaccination as a social norm” and “reliability of vaccine supply” are key shared predictors across both parent groups. In addition, parents with more than one child are more likely to perceive vaccination as part of a healthy lifestyle, whereas some first-time parents believe that “vaccination is not their responsibility.”
The study concludes that first-time parents tend to have lower vaccination rates and higher levels of hesitancy for their children’s influenza vaccines—particularly before the age of three—and these patterns are strongly shaped by social norms and vaccine confidence. The authors recommend adopting birth-order–specific strategies to promote immunization, thereby improving equity and coverage in pediatric influenza vaccination.
https://doi.org/10.1080/14760584.2025.2576235
Content Editor: Tianyi Deng
Page Editor: Ruitong Li
