Willingness to receive future COVID-19 vaccines following the COVID-19 epidemic in Shanghai, China.

BACKGROUND: There are no pharmacological interventions currently available to prevent the transmission of SARS-CoV-2 or to treat COVID-19. The development of vaccines against COVID-19 is essential to contain the pandemic. we conducted a cross-sectional survey of Shanghai residents to understand residents' willingness to be vaccinated with any future COVID-19 vaccines and take measures to further improve vaccination coverage. METHODS: We conducted a cross-sectional survey using self-administered anonymous questionnaires from 1 July to 8 September 2020. The main outcome was willingness of participants, and any children or older individuals living with them, to receive future COVID-19 vaccines. Logistic regression analyses were used to explore potential factors associated with vaccination willingness. RESULTS: A total of 1071 participants were asked about their willingness to receive future COVID-19 vaccines, for themselves and at least 747 children and 375 older individuals (≥60 years old) living with them. The highest proportion of expected willingness to vaccinate was among participants (88.6%), followed by children (85.3%) and older individuals (84.0%). The main reasons for reluctance to vaccinate among 119 participants were doubts regarding vaccine safety (60.0%) and efficacy (28.8%). Participants with a self-reported history of influenza vaccination were more likely to accept COVID-19 vaccines for themselves [adjusted odds ratio (OR) = 1.83; 95% confidence interval (CI): 1.19-2.82], their children (adjusted OR = 2.08; 95%CI: 1.30-3.33), and older individuals in their household (adjusted OR = 2.12; 95%CI: 1.14-3.99). Participants with older individuals in their families were less willing to vaccinate themselves (adjusted OR = 0.59; 95%CI: 0.40-0.87) and their children (adjusted OR = 0.58; 95%CI: 0.38-0.89). CONCLUSIONS: Participants were more reluctant to accept COVID-19 vaccines for older individuals living with them. The presence of older individuals in the home also affected willingness of participants and their children to be vaccinated.

Characteristics of within-household varicella transmission events associated with school outbreaks in Shanghai, China, 2009-2018.

Transmission of varicella occurs frequently in schools and households. We investigated the characteristics of varicella cases derived from within-household transmission and the modes of varicella transmission between school and household settings in Shanghai, China, from 2009 to 2018. Within-household transmission occurred in 278 households, of which 134 transmission events were between children. Sixty-one household varicella transmission events may be attributed to isolation procedures for infected students during school outbreaks, and 7.6% of school outbreaks were caused by schoolchildren cases derived from within-household transmission. The frequency of 'school-household-school' transmission adds an additional layer of complexity to the control of school varicella outbreaks. Administration of varicella vaccine as post-exposure prophylaxis after exposure is considered to be an effective measure to control varicella spread within households and schools.

Norovirus shedding among symptomatic and asymptomatic employees in outbreak settings in Shanghai, China.

BACKGROUND: Norovirus (NoV) is recognized as a leading cause of acute gastroenteritis (AGE) outbreaks in settings globally. Studies have shown that employees played an important role in the transmission mode during some NoV outbreaks. This study aimed to investigate the prevalence of NoV infection and duration of NoV shedding among employees during NoV outbreaks, as well as factors affecting shedding duration. METHODS: Specimens and epidemiological data were collected from employees who were suspected of being involved in the transmission or with AGE symptoms during NoV outbreaks in Xuhui District, Shanghai, from 2015 to 2017. Specimens were detected using real-time RT-PCR to determine whether or not employees had become infected with NoV. Specimens were collected every 3-7 days from NoV-infected employees until specimens became negative for NoV. RESULTS: A total of 421 employees were sampled from 49 NoV outbreaks, and nearly 90% of them (377/421) were asymptomatic. Symptomatic employees showed significantly higher prevalence of NoV infection than asymptomatic ones (70.5% vs. 17.0%, P < 0.01). The average duration of NoV shedding was 6.9 days (95% confidence interval: 6.1-7.7 days) among 88 NoV-infected individuals, and was significantly longer in symptomatic individuals than in asymptomatic ones (9.8 days vs. 5.6 days, P < 0.01). In Cox proportional-hazards model, after adjusting age and gender, symptoms was the only factor associated with duration of NoV shedding. CONCLUSIONS: Compared with asymptomatic employees, symptomatic employees had higher prevalence of NoV infection and longer durations of NoV shedding. Since NoV shedding duration among NoV-infected employees tends to be longer than their isolation time during outbreaks, reinforcement of hygiene practices among these employees is especially necessary to reduce the risk of virus secondary transmissions after their return to work.

HENOCH-SCHÖNLEIN PURPURA NEPHRITIS FOLLOWING INFLUENZA VACCINATION: A CASE REPORT AND REVIEW OF THE LITERATURE

We reported a 16-year-old boy who developed Henoch-Schönlein purpura (HSP) 15 days after receiving a seasonal influenza vaccine. His symptoms improved temporally with treatment but he developed HSP nephritis (HSPN) that relapsed multiple times over the following three years. This case of Henoch-Schönlein purpura may have been due to the seasonal influenza vaccine. The mechanism for this association is unclear. Practitioners should be aware of this possible complication.

Characteristics and factors of repeated influenza vaccination among elderly individuals in Shanghai, China from 2020 to 2022.

Elderly individuals face a high risk of hospitalization and death related to influenza, thus prioritizing them for influenza vaccination. Due to variations in the influenza virus and waning protective antibodies, annual influenza vaccination is recommended. However, research on repeated influenza vaccination among elderly individuals in China is limited. From 2020 to 2022, the average influenza vaccination coverage among registered elderly individuals in Shanghai was 4.1%, showing a declining trend over time. In 2020, the rate of repeated influenza vaccination among elderly individuals was 28.35%, which rose to almost two-thirds both in 2021 and 2022. No increased risk of adverse events following immunization was observed after repeated influenza vaccination during this period. Our study also found that elderly individuals with Shanghai household registration, managed by community clinics, and older age tended to receive more doses of repeated influenza vaccination throughout the period from 2020 to 2022. Increasing influenza vaccine coverage among elderly individuals in Shanghai is both urgent and challenging. Health authorities should intensify educational and promotional campaigns to encourage uptake of annual repeated influenza vaccination among elderly individuals.

Epidemiological characteristics and trends of Bacillus Calmette-Guérin lymphadenitis in Shanghai, China from 2010 to 2019.

Although the administration of the Bacillus Calmette-Guérin (BCG) vaccine is generally safe, lymphadenitis, the most common complication of BCG vaccination, can occur. Here, we describe the epidemiological characteristics and incidence trends of BCG lymphadenitis in Shanghai, China, among a population with a high burden of tuberculosis. A total of 56 cases of adverse events following immunization (AEFI) after BCG vaccination were reported in Shanghai, including 51 cases of BCG lymphadenitis (91.07%), from 2010 to 2019. The general incidence of BCG lymphadenitis was 173 per 1,000,000 doses in Shanghai from 2010 to 2019. A nonsignificant increase of 58.81% per year was observed between 2010 and 2012 (t = 0.93; p = .40), followed by a significant decline of 28.00% per year from 2012 to 2019 (t = -4.27; p < .01). Seven batches of BCG vaccines triggered three or more BCG lymphadenitis cases, for 27 (52.94%) cases in total. We identified two patients with immunodeficiency of chronic granulomatous disease, one of whom died four years later after BCG vaccination and another of whom was still being treated after two transplants. The average total care cost of the 47 recovered cases was 11,336 RMB (range: 2,637-33,861 RMB). Due to the high burden of BCG lymphadenitis, especially in children with immunodeficiency, it is suggested that government departments should strengthen healthcare provider training, assign specific nurses to perform BCG vaccination, monitor vaccinated individuals actively and timely detect abnormal signals so as to reduce the incidence of BCG lymphadenitis.

Effectiveness of varicella vaccine as post-exposure prophylaxis: a meta-analysis.

BACKGROUND: To evaluate the effectiveness of varicella vaccine (VarV) as post-exposure prophylaxis (PEP) among children during varicella outbreaks. MATERIAL AND METHODS: A comprehensive literature search was performed in PubMed, Embase, Web of Science, SinoMed, Wanfang and CNKI. Relevant outcomes included the incidence of varicella. Pooled estimates were calculated using a fixed-effects or random-effects model according to the heterogeneity among studies. RESULTS: A total of 15 studies with 7,474 children that received one or two dosages of VarV as PEP and 183,827 children who received no VarV were included in the meta-analysis. In total, one-dose and two-dose VarV as PEP had 43% (95% confidence interval (CI):27%, 55%) and 60% (95%CI: 35%, 75%) efficacy, respectively. When PEP was applied within 3 days, the pooled VarV as PEP for prevention of varicella was 80% (95%CI: 68%, 88%); when PEP was administered beyond 3 days, the pooled VarV as PEP for the prevention of varicella was 50% (95%CI: 11%, 72%). If the PEP was implemented with a coverage of more than 80%, the VarV could prevent 82% of varicella cases from occurring (95%CI: 15%, 96%); if the PEP covered a maximum of 80% of the susceptible cases, the VarV could prevent 65% of varicella cases from occurring (95%CI: 50%, 76%). CONCLUSION: The two-dose VarV had better efficacy than one-dose VarV in the control of varicella outbreaks, especially if PEP was applied within 3 days of an outbreak and in conjunction with a high coverage rate ≥80%.

Impact of the coronavirus disease 2019 epidemic and a free influenza vaccine strategy on the willingness of residents to receive influenza vaccines in Shanghai, China.

The influenza vaccine is not included in China's national immunization program. Here, we assessed influenza vaccine coverage among Shanghai residents and estimated the impacts of the coronavirus disease 2019 (COVID-19) epidemic and a hypothetical free vaccine strategy on the willingness of participants to receive influenza vaccines. The coverage of influenza vaccines among Shanghai residents from 2015 to 2019 was 1.4% (range: 1%-2.4%). A total of 792 adult participants (aged 19-59 years) along with 821 children and 445 older individuals were included in the analysis. The willingness of participants to receive influenza vaccines reached 68.4% following the COVID-19 epidemic. Furthermore, if the vaccine was made available at no cost, 85.9% of participants were willing to be vaccinated. Our data indicated that influenza vaccine coverage is extremely low in Shanghai but that more than two-thirds of participants were willing to receive influenza vaccines following the COVID-19 epidemic. Making influenza vaccines available for free could further increase coverage.

Two cases of disseminated BCG disease following vaccination in the same family: case reports and review of the literature in China.

Disseminated bacillus Calmette-Guérin (BCG) disease is a rare and serious adverse event following immunization (AEFI) with BCG. Here, we reported two cases of disseminated BCG disease in the same family and reviewed the literature to identify another 35 cases in China. The average age at onset was 3.7 ± 2.1 months among the 37 cases and only 21 cases (56.8%) were laboratory confirmed. Of the 37 cases, 22 were evaluated for immunodeficiency; definite immunodeficiency was observed in 16 cases (72.7%) and could not be excluded in the other six cases (27.3%). Following treatment, 20 of the 37 cases died (54.1%), one case developed sequelae (2.7%), four cases had progressive disease (10.8%), nine cases had stable disease (24.3%), and only three cases were cured (8.1%). Vaccination of infants with BCG is cost-effective and should not be stopped because of the possibility of rare disseminated BCG disease, especially in countries with high tuberculosis burdens such as China. However, infants with a family history of immunodeficiency should be vaccinated after excluding immunodeficiency-related diseases to minimize the risk of disseminated BCG disease. Furthermore, government should strengthen proactive surveillance programs to detect and treat rare AEFIs early and improve disease outcomes.

Low vaccination coverage of pneumococcal conjugate vaccines (PCVs) in Shanghai, China: A database analysis based on birth cohorts from 2012 to 2020.

BACKGROUND: Pneumococcal vaccines have been developed to protect infants and young children from pneumococcal diseases. Vaccination coverage studies are important in determining a population's vaccination status and strategically adjusting national immunization programs (NIP). In this paper, we aim to describe the coverage of pneumococcal conjugate vaccines (PCVs) immunization for birth cohorts from 2012 to 2020 and discussed the factors influencing the coverage. METHODS: Vaccination data were collected via the vaccination information database in Shanghai, China, for children born from 2012 to 2020. The population data used in this study were collected from each community from 2012 to 2020. The coverage of initial immunization (1st dose), basic immunization (three doses) and full immunization (3 + 1 doses) for PCVs was calculated according to the number of doses received. As vaccination coverage was assessed each year, Annual Growth Rate (AGR) was used to describe the variation trend of vaccination coverage. Immunization time and completeness of different PCVs were also analyzed. RESULTS: The total number of births from 2012 to 2020 was 38,268 in Huangpu District, Shanghai, China. The initial immunization coverage of PCVs increased from 12.26% in 2012 to 49.65% in 2020, and the highest coverage was 50.61% in 2019. The cumulative vaccination coverage of PCVs was 19.4% for initial immunization and 16.8% for basic immunization from 2012 to 2020. And cumulative full immunization coverage of PCVs was 12.3% from 2012 to 2019. The PCVs coverage of most vaccination statuses showed an obvious upward trend from 2017 to 2020. CONCLUSIONS: Despite an upward trend in vaccination coverage of PCVs, the vaccination coverage of initial, basic and full immunization among children is still low. And given the heavy burden of Streptococcus pneumoniae (Sp) among children in China and the fact that the current vaccination coverage cannot effectively protect children, it is recommended that the government include PCVs into the NIP as soon as possible.

Changes in epidemiological features of vaccine preventable infectious diseases among three eras of national vaccination strategies from 1953 to 2018 in Shanghai, China.

BACKGROUND: Recurring outbreaks of infectious diseases highlight the importance of population vaccination strategies. We aimed to assess the impact of national vaccination strategies on vaccine-preventable infectious diseases (VPDs) in Shanghai, China and to identify vulnerable groups that may benefit from future vaccination policies. METHODS: Infectious disease data from 1953 to 2018 was obtained from Xuhui District Center for Disease Control and Prevention, Shanghai China. We used joinpoint regression to show incidence, mortality and fatality trends and to determine annual percent change in incidence of 12 VPDs among three eras of national immunization strategies: (1)1953-1977, (2)1978-2007, and(3)2008-2018. FINDINGS: Incidence, mortality, and fatality from VPDs have decreased drastically over the three eras, despite the inclusion of more diseases over time. Strikingly, the overall yearly incidence of VPDs shows an increasing trend from 2000 to 2018 in Shanghai (annual percentage changes, APC:7.7, p = 0.025). In the third era (2008-2018), the three VPDs with the highest incidence were varicella (80.2 cases/100,000), hand, foot, and mouth disease (HFMD) (73.6 cases/100,000), and hepatitis (43.5 cases/100,000). A significant upward trend was also observed in hepatitis (APC:24.9, p<0.001), varicella (APC:5.9, p = 0.006), and HFMD (APC:11.8, p = 0.003) from 2008-2018. Hepatitis and tuberculosis are the only VPDs with fatality cases in this period. INTERPRETATION: Focus is needed in controlling adult hepatitis and tuberculosis, either by introducing adult booster vaccines or by research into more effective vaccines. Varicella and HFMD are on the rise, but vaccines for these are not included in national programs. Strategies funded by government agencies or encouraged by research incentives are needed for varicella and HFMD, such as two-dose and novel multi-valent vaccines, respectively. FUNDING: Chinese Ministry of Education, Shanghai Municipal Government.

Factors Influencing the Size and Duration of School Varicella Outbreaks in Shanghai, China, in the Era of Voluntary Single-Dose Vaccination.

Varicella outbreaks continue to occur in schools. We assessed potential factors associated with the size and duration of 560 school-based outbreaks in Shanghai, China. Outbreaks occurring in primary and middle schools involved more cases and had longer durations, and conducting postexposure prophylaxis campaigns was an effective strategy for outbreak control.

Varicella outbreak trends in school settings during the voluntary single-dose vaccine era from 2006 to 2017 in Shanghai, China.

OBJECTIVE: To investigate varicella outbreak trends among schoolchildren during the voluntary single-dose varicella vaccine (VarV) era in Shanghai, China. METHODS: Trends in school varicella outbreaks from 2006 to 2017 were assessed using joinpoint regression models. The impacts of changes in single-dose VarV coverage among schoolchildren and implementation of post-exposure prophylaxis (PEP) strategies on outbreak trends were further analyzed. RESULTS: In total, 265 varicella outbreaks involving 3263 cases were reported in Shanghai from 2006 to 2017. The number of outbreaks showed an increasing trend from 2006 to 2017 (t=2.62, p=0.026), especially in kindergartens. The proportion of breakthrough varicella cases among all outbreak-related cases showed an increasing trend from 30.4% in 2008 to 85.7% in 2017 (t=7.45, p<0.001). Single-dose VarV coverage among schoolchildren was 88.1%, and showed a significant increase from the 1996 to the 2008 birth cohorts, followed by a non-significant decline from the 2008 to the 2014 birth cohorts. During school outbreaks in which PEP campaigns were conducted, the varicella attack rate was significantly lower than those in outbreaks without PEP campaigns (1.2% vs. 1.4%; Chi-square=23.35, p<0.001). CONCLUSIONS: Even with high coverage, single-dose VarV is insufficient to prevent school outbreaks. The administration of VarV as PEP is an appropriate intervention for varicella outbreak control prior to implementing a two-dose VarV schedule.

Effectiveness of varicella vaccine as post-exposure prophylaxis during a varicella outbreak in Shanghai, China.

OBJECTIVES: Varicella vaccine (VarV) is recommended as effective post-exposure prophylaxis (PEP) within 3-5days to control outbreaks. However, the effectiveness of PEP at >5days after exposure and the administration of a second dose to those with a history of one dose prior to exposure have not been fully examined. This study evaluated the vaccine effectiveness (VE) of PEP in preventing disease during a varicella outbreak in Shanghai, China in 2013. METHODS: Self-administered questionnaires were used to obtain the students' varicella history, vaccination status, and willingness to receive PEP. One dose of VarV was provided free of charge to eligible students. The VE of PEP was calculated as [1-relative risk (RR)]×100%. Analyses were restricted to grade 8 students, as no students from the other grades or teachers developed varicella during the outbreak. RESULTS: Twenty-seven varicella cases were identified, 16 (59%) of which were infected after the PEP campaign. Sixty-five students received one dose of VarV on day 13 or 19 after the index case. Attack rates were 28% (9/32), 16% (15/94), 0% (0/10), and 6% (3/55) among unvaccinated, one-dose Pre-PEP, first dose as PEP, and second dose as PEP recipients, respectively. Cases among second dose as PEP recipients tended to have less fever compared with unvaccinated or one-dose Pre-PEP recipients. Compared with unvaccinated students, the VE of first dose as PEP recipients was 100% and of the second dose as PEP recipients was 60% (95% confidence interval -72% to 91%). CONCLUSIONS: Post-exposure vaccination should be given as soon as possible after exposure. Nevertheless, vaccination is still recommended even at more than 5days post-exposure to control varicella outbreaks.

Analysis of the duration of Noravirus shedding among infected kindergarten children during an outbreak / 中国学校卫生

Objective@#To investigate the duration of Norovirus (NoV) shedding among infected school children during a NoV outbreak in a kindergarten,and to provide scientitic basis for epidemic prevention and control.@*Methods@#Specimens and epidemiological data were collected from suspected cases, and specimens were detected using real-time RT-PCR to determine whether or not infecting with NoV. Specimens were collected every 3-7 days from NoV-infected children until specimens became negative for NoV.@*Results@#A total of 14 suspected cases were reported, and 12 of them were infected with NoV. The average duration of NoV shedding was (26.58±17.94)d. The specimens among 9 from 12 Nov-infected cases were positive at 7 days, 8 NoV-intected cased remained positive at 14 days and 7 Non-infected cased at least 21 days.@*Conclusion@#Since NoV shedding duration among NoV-infected children tends to longer than their isolation time during outbreaks, reinforcement of hygiene practices among these school children is especially necessary to reduce the risk of virus secondary transmissions after their return to school.