What is already known about this topic?:The inclusion of meningococcal vaccines in the National Immunization Program (NIP) over several years has significantly reduced the incidence of meningococcal meningitis in China to historic lows. Worldwide, there has been a diversification of meningococcal serogroups, leading to a shift in dominant serogroups in China from serogroup A to serogroups C and B, accompanied by a rise in reports of serogroups Y and W.What is added by this report?:An outbreak of serogroup Y Neisseria meningitidis (Nm) in a secondary vocational school involved a single confirmed severe case and 24 individuals with laboratory-confirmed Nm carriage. Epidemiological investigation revealed that the outbreak was localized to the classroom of the confirmed case. Prolonged close contact within a confined space was identified as a significant risk factor for Nm transmission. The genotype sequence identified was type 1655 (ST-1655), which is categorized under clonal complex 23 (CC-23) and bears resemblance to 8 previously confirmed cases of serogroup Y meningococcal meningitis within Guangdong Province. This suggests that serogroup Y infections continue to sporadically emerge and have become prevalent strains.What are the implications for public health practice?:This outbreak underscores the critical need to enhance surveillance of meningococcal serogroups and population carrier, and advocate for vaccination with MenY-containing vaccines.

Background: Influenza vaccination is an important prevention strategy for flu illness. However, the vaccination rate is still low in Guangzhou, China. This study aimed to understand the status of knowledge, the attitude towards the vaccines’ reliability and safety, and other aspects associated with the willingness and practice of influenza vaccines in the pediatric and adult populations of Guangzhou city. Methods: This study was performed in eleven districts in Guangzhou between November 2020 and December 2020, including the Yuexiu, Liwan, Haizhu, Tianhe, Baiyun, Panyu, Huadu, Nansha, Huangpu, Zengcheng, and Conghua districts. The parents of children and teenagers under the age of eighteen in Guangzhou were surveyed using self-administered questionnaires in four domains: demographic information, the knowledge status and perception of influenza vaccination, the willingness and attitude towards influenza vaccination, and previous vaccine uptake. A multivariable logistic regression was employed to assess the possible determinants of willingness and practice to receive influenza vaccination, calculating the odds ratios (ORs) and 95% confidence interval (CI). A two-sided p-value < 0.05 was deemed statistically significant. Results: A total of 13,213 valid questionnaires were collected (validity rate 98.8%). Out of these participants, 42.62% (5631 participants) expressed a willingness to receive the influenza vaccine, while 55.40% (7320 participants) reported that their children and teenagers had been vaccinated against the flu. Furthermore, 40.44% of the respondents (5343 participants) or other family members had received the influenza vaccine. Logistic regression indicated that factors such as being female (OR = 1.395, 95% CI: 1.278–1.522), being involved in the work of COVID-19 prevention and control (1.551, 1.396–1.724), affirming the preventive effects of vaccination (2.474, 2.106–2.906), knowing about annual influenza vaccination (2.756, 2.540–2.992), and understanding prioritized influenza vaccination populations (1.464, 1.343–1.596) were all positively associated with vaccination willingness. Conversely, middle-aged persons (aged 40–49 years old) (0.726, 0.617–0.853), higher educational levels (undergraduate versus middle school) (0.858, 0.768–0.959), heightened concerns about vaccine safety (considering side effects are obvious versus considering it is safe and basically no side effects) (0.284, 0.188–0.429) and lower knowledge scores (0.813, 0.701–0.942) were adversely linked with vaccination willingness. Conclusion: These findings provide essential insights for altering the perception of influence and influenza vaccination, as well as enhancing health communication strategies to improve influenza vaccine uptake among Guangzhou residents.

Abstract: Influenza-like illness (ILI) outbreaks mainly occurred in schools. And annually reformulated composition of influenza vaccines makes it necessary to estimate the effectiveness of the seasonal influenza vaccine. We aimed to estimate the effectiveness of the seasonal influenza vaccine against influenza outbreaks in schools. Methods This was a matched case-control study estimating the effectiveness of the influenza vaccine in preventing school influenza outbreaks. The laboratory-confirmed cases of influenza in school children were paired by the random sample of asymptomatic classmates by sex and age during the 2019–2020 influenza season. Influenza vaccine effectiveness was estimated using a conditional logistic regression model. Results During the 2019–2020 influenza season, 503 paired samples of laboratory-confirmed influenza cases and asymptomatic controls were enrolled. The influenza vaccination rates for cases and controls were 0.40% and 1.59%, respectively. The vaccine effectiveness against influenza outbreaks in schools was 74.35% (95% CI: 5.39–122.00) during the 2019–2020 season. Conclusions No significant vaccine effectiveness was observed during influenza outbreaks in schools during the 2019–2020 influenza season because of the low vaccination rate. Efforts should be made to increase vaccination coverage among students.

Background: As measles vaccination coverage has increased, measles infection has shifted to the population of infants. We conducted a follow-up seroepidemiological study among mothers and their infants to evaluate measles seroprevalence and the persistence of maternal measles antibody in Shufu, Kashgar from 2018 to 2020.Methods: Maternal venous blood and cord blood was obtained among mothers and their infants at 0, 3, 5, 8, 9, and 12 months of age. An enzyme-linked immunosorbent assay was used for quantitative measurement of measles antibodies. We analyzed the correlation between maternal and neonatal measles antibodies, and antibodies persistence after infants were born.Results: The overall neonatal maternal ratio was 2.38 (95%CI: 2.05-2.71). The measles antibodies for mothers and newborns were 438.93 IU/mL (95%CI: 409.47-470.51 IU/mL) and 440.10 IU/mL (95%CI: 410.82-471.48 IU/mL), respectively. Neonatal measles antibodies were dropping after birth and then beginning to increase starting at 8 months of age.Conclusions: Infant measles antibody levels progressively declined after birth regardless of maternal measles antibody levels. Efforts should be carried out to eliminate measles.

Background We conducted a matched case–control study in China during the 2013/14–2015/16 influenza seasons to estimate influenza vaccine effectiveness (VE) by dose among children aged 6 months to 8 years. Methods Cases were laboratory-confirmed influenza infections identified through the influenza-like illness sentinel surveillance network in Guangzhou. Age- and sex-matched community controls were randomly selected through the expanded immunization program database. We defined priming as receipt of ≥1 dose of influenza vaccine during the immediate prior season. Results In total, 4,185 case–control pairs were analyzed. Among children 6–35 months, VE for current season dose(s) across the three seasons during 2013/14–2015/16 were 59% (95% Confidence Interval: 44–71%), 12% (−11%,30%), 54% (32–69%); among unprimed children 6–35 months, VE for 1 vs 2 current season doses were 45% (8–67%) vs 65% (46–78%), −2% (−53%,32%) vs 19% (−11%,40%), and 37% (−24%,68%) vs 61% (32–78%). Among children aged 3–8 years, VE for current season dose(s) across study seasons were 62% (36–78%), 43% (22–58%), 32% (1–53%). VE for unprimed children receiving 1 dose only in current season was insignificant or lower than among all children. Conclusion Findings support utility of providing second dose (“booster dose”) of seasonal influenza vaccine to unprimed children aged 6–35 months, and the need to study further dose effect of a booster dose among unprimed children aged 3–8 years in China.

Maternal antibodies transported across the placenta can provide vital immunity against infectious pathogens for infants. We here examine maternal antibody (MA) levels and their association with neonatal antibody levels. Pregnant women of gestational age ≥35 weeks were enrolled at a Guangzhou China hospital and mother-infant paired sera were collected. Measles IgG antibody was detected using ELISA assay, neutralizing antibodies titers against coxsackievirus A16 (CA16), enterovirus 71 (EV71), PV I-III and HIV-1 were performed. 711 mother-infant pairs were enrolled and positive relationships for paired serums were found (r: 0.683–0.918). 81.6%, 87.0%, and 82.3% of mothers, and 87.3%, 72.7%, and 72.2% of newborns were positive for measles, CA16 and EV71 antibodies respectively. The highest Neonatal: maternal ratio (NMR) was found in measles (1.042) and the ratios for the other pathogens ranged from 0.84 to 1.00. Linear regressions showed that log(NMR) decreased by a factor of 0.04–15.43 as log(MA) levels increased. A second analysis restricted to maternal positive measles sera revealed that MA measles of was still inversely associated with NMR. Low NMR was found in high MA HIV + serums among 22 paired sera. MA levels appear to play a role determining transplacental antibody transfer; further study is needed to reveal the mechanism.

目的 评价季节性流行性感冒疫苗(流感疫苗)对儿童新甲型H1N1流感保护效果.方法 选择2013年2～6月期间6～59月龄的实验室确诊流感病例为病例组,在儿童预防接种信息系统中随机选择健康儿童为对照组,进行1∶1匹配的病例对照研究,采用条件Logistic回归计算保护效果.结果 本研究共纳入1 250对研究对象.2013年2～6月流感疫苗对6～59月龄儿童的保护效果为57.7％ (95 ％CI:46.6％～66.4％),对36～59月龄儿童的保护效果优于6～35月龄儿童,完全免疫的保护效果优于部分免疫,仅研究年度免疫与两个年度均免疫的儿童的保护效果差异无统计学意义.结论 流感疫苗对儿童新甲型H1N1流感具有中等的保护效果,建议儿童每年及时进行全程免疫.

Background: Since the National Expanded Program on Immunization was implemented in China, considerable progress has been made in reducing the incidence of measles. However, the incidence of measles increased again in 2004. Few post-marketing studies on measles vaccine effectiveness were reported in China. In this study, we aimed to describe the measles epidemic and to evaluate the effectiveness of the measles vaccine in Guangzhou, southern China.Methods: Based on the surveillance data for measles, we investigated the epidemiology during different periods between 1951 and 2012. We analyzed the clinical characteristics of laboratory-confirmed cases of measles between 2009 and 2012 and conducted a case-control study using test-negative cases as controls. We determined the protective effect of measles vaccine.Results: The highest annual incidence in Guangzhou was 2187.15/100000 in 1964, and the lowest was 0.32/100000 in 2011. The average incidence of measles from 1951 to 2012 was 306.27/100000. There was a significant tendency of decline in recent years. From 2009 to 2012, there are 700 laboratory-confirmed cases reported with an average onset age of 2.5 (median) years. The non-vaccinated target population (age <8 months and >= 15 years) accounted for 56.7% of the cases. The transient (non-resident) population accounted for 51.3% of the cases. Fewer cases were observed in the population targeted for measles vaccine (aged 8 months to 14 years). The effectiveness of a single dose of the measles vaccine was 89.1% (95% confidence interval (CI), 44.5-97.9), and the effectiveness of >= 2 doses of the measles vaccine was 97.8% (95% CI, 88.3-99.6) in children aged 8 months to 14 years old.Conclusions: There is a significant overall decline in the incidence of measles (including clinical and laboratory confirmed cases) in the measles vaccine targeted population in Guangzhou. Two doses of measles vaccine are more effective than one dose in preventing measles in China. In order to accelerate the elimination of measles, vaccination should also be given to the transient and the non-vaccine targeted population.

ObjectiveWe aimed to estimate the Lanzhou lamb rotavirus (LLR) vaccination coverage (VC) and timeliness among children aged 2 to 59 months in Guangzhou, China. MethodsAn electronic system-based VC survey was conducted using stratified cluster random sampling. ResultsWe reported an overall Lanzhou lamb rotavirus vaccine coverage of 25.3% among children aged 2-59 months (2-8 months, 2.6%) in Guangzhou, China. ConclusionGreat efforts should be taken to increase LLR VC in eligible children in Guangzhou, China.

Influenza vaccine has to be reformulated each year due to the ever-changing antigenicity of the influenza virus. However, few post-licensure studies of influenza vaccine are available in China. We aimed to measure the effectiveness of seasonal influenza vaccine during 2 consecutive seasons. Among children in Guangzhou aged 6 to 59 mo in 2010-2012, we matched each child with clinically diagnosed influenza to 3 healthy children. Cases with clinically diagnosed influenza were identified from surveillance system. Healthy controls were randomly sampled from the Children's Expanded Programmed Immunization Administrative Computerized System. Conditional logistic regression was used to calculate vaccine effectiveness (VE). A total of 275 matched sets of subjects were included. VE levels against clinically diagnosed influenza for both seasons combined was 47.4% [95% confidence interval (CI), 8.5-69.8%] for full vaccination for children aged 6-35 mo, 33.6% (95% CI, 5.4-53.5%) for any vaccination for children aged 6-59 mo, respectively. VE by time since vaccination for any vaccination was 34.6% (95% CI, 4.7-55.2%) in 0-5 mo, and no protection was observed in 6-11 mo. Annual, full and timely vaccination should be encouraged for children.

Background The annual differences in the seasonal influenza vaccine and the circulating strains make it necessary to assess influenza vaccine effectiveness ( VE ) yearly. We assessed the effectiveness of the trivalent inactivated influenza vaccine for the 2010–2011 and 2011–2012 influenza seasons among children in Guangzhou, China. Methods We conducted a 1:2 matched case–control study based on date of birth (±7 days), gender, and area of residence. The influenza cases from surveillance sites in Guangzhou were laboratory‐confirmed during the 2010–2012 seasons. The controls were randomly selected from children aged 6–59 months in the Children's Expanded Programmed Immunization Administrative Computerized System. The influenza vaccination information for both cases and controls was retrieved from this system. Results We analyzed the vaccination information for 1255 influenza cases and 2510 matched controls in 2 influenza seasons in Guangzhou, China. We found that the VE for vaccination during the 2010–2011 and 2011–2012 seasons of virus circulation was 73·2% (95% confidence interval ( CI ), 52·2–85·0%) and 52·9% (95% CI , 42·1–61·7%), respectively. The VE decreased from 68·9% (95% CI , 57·5–77·2%) in the period between January and March to 48·4% (95% CI , 33·8–59·7%) in the period between April and June. Conclusions This post‐licensing study of VE found moderate protection against influenza for vaccinated children aged 6–59 months. Although the influenza vaccine strains for the 2010–2011 and the 2011–2012 seasons were the same, our study indicated that annual vaccination is recommended even for those who received the vaccine during the previous season.

Although mumps-containing vaccines were introduced in China in 1990s, mumps continues to be a public health concern due to the lack of decline in reported mumps cases. To assess the mumps vaccine effectiveness (VE) in Guangzhou, China, we performed a 1: 1 matched case-control study. Among children in Guangzhou aged 8 mo to 12 y during 2006 to 2012, we matched one healthy child to each child with clinically diagnosed mumps. Cases with clinically diagnosed mumps were identified from surveillance sites system and healthy controls were randomly sampled from the Children's Expanded Programmed Immunization Administrative Computerized System in Guangzhou. Conditional logistic regression was used to calculate VE. We analyzed the vaccination information for 1983 mumps case subjects and 1983 matched controls and found that the overall VE for 1 dose of mumps vaccine, irrespective of the manufacture, was 53.6% (95% confidence interval [CI], 41.0-63.5%) to children aged 8 mo to 12 y. This post-marketing mumps VE study found that immunization with one dose of the mumps vaccine confers partial protection against mumps disease. Evaluation of the VE for the current mumps vaccines, introduction of a second dose of mumps vaccine, and assessment of modifications to childhood immunization schedules is essential.

Influenza causes more morbidity than any other vaccine-preventable illness and leads to an estimated 50 to 95 outpatient visits, 6 to 27 emergency department visits, and 30 to 90 courses of antibiotics each year per 1000 children aged less than 5 y. Immunization recommended each year is the major public health measure for the prevention of influenza virus infection. The differences in match between vaccine and circulating strains make it necessary to assess influenza vaccine effectiveness (VE) each year. In this study, we assessed the effectiveness of the trivalent inactivated influenza vaccine against laboratory-confirmed influenza for the 2010–11 influenza season among children in Guangzhou, the central city in southern China.