Two-dose varicella vaccine effectiveness in China: a meta-analysis and evidence quality assessment.

BACKGROUND: The objectives of this review were to evaluate the vaccine effectiveness (VE) of the two-dose varicella vaccine for healthy children in China and explore the application of the approach of Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) in observational studies on VE. METHODS: We searched for observational studies on two-dose varicella VE for children in China aged 1-12 years that were published from 1997 to 2019, and assessed the quality of each study using the Newcastle Ottawa Scale (NOS). We used meta-analysis models to obtain the pooled two-dose VE, and the studies were divided into subgroups and analysed according to whether or not it was an outbreak investigation and its NOS score. The quality of evidence of VEs were rated by approach of the GRADE system. RESULTS: A total of 12 studies and 87,196 individuals were included. The pooled two-dose VE was 90% (95% confidence interval [CI]: 69-97%). The VE of outbreak studies (87% [95% CI: 76-93%]) was lower than non-outbreak studies (99% [95% CI: 98-99%]). There was no significant difference in VEs by different NOS quality. The quality of the evidence assessment of pooled two-dose VE was "low", which was rated down by one category in limitations and publication bias respectively and rated up by two category in large effect. The quality of evidence assessment in subgroup of NOS score ≥ 7 was "moderate". CONCLUSIONS: The VE of two-dose varicella vaccine is relatively high in preventing varicella, and is recommended for countries which need further control for varicella. However, higher quality evidence is needed as a supplement for stronger recommendations. The approach of GRADE could be applied for rating the quality of evidence in observational study.

[Analysis of antibodies of poliviruses in persistent populations in Beijing, 2012].

OBJECTIVE: To analyze the polio immunity level of persistent population in Beijing, 2012. METHODS: A total of 1 676 subjects residing more than 6 months in Beijing were selected by stratified random cluster sampling design in 2012. Demographic characteristics, history of oral poliovirus vaccine (OPV) immunization were investigated by questionnaire. All 5 ml blood sample were collected for testing of polio neutralizing antibody using the method of microcell neutralization. The positive rate and the geometric mean titer (GMT) of polio neutralizing antibody type I, II and III were analyzed in different groups. RESULTS: The positive rate of type I, II and III were 98.2% (1 645/1 676), 98.1% (1 644/1 676), 97.6% (1 635/1 676); The GMT were 1:130.2, 1: 113.4 and 1: 79.7. Three types of positive rates in<15 years group (99.7% (664/666), 99.8% (665/666), 99.5% (663/666)) were higher than those of ≥ 15 years group (97.1% (981/1 010), 96.9% (979/1 010), 96.2% (972/1 010)), the differences were significant (all the values of P < 0.01); The GMT in<15 years group (1:325.9, 1:250.5, 1:190.7) were higher than that of ≥ 15 years group (1: 71.1, 1: 67.2, 1: 44.8), the difference was significant (all the values of P < 0.01). The positive rate (99.0%-100%) and GMT (1: 128.8-1: 300.7) in vaccination information confirmed population were higher. The highest positive rate (all were 100%) and GMT(1: 409.7-1: 636.7) were observed in children who vaccinated three times. CONCLUSION: The polio antibody of healthy population was at a high level in Beijing in 2012; Especially the age groups of < 15 years which were covered by vaccines.Immunization barrier had been formed firmly to interrupt the transmission of wild poliovirus and vaccine-derived poliovirus.

[Analysis of measles immunity level in persistent populations in Beijing, 2012].

OBJECTIVE: To analyze the measles immunity level of persistent population in Beijing. METHODS: A total of 2125 objects from 10 age groups, who had been living in Beijing for over 6 months, were selected from urban and rural areas in Beijing in 2012. Demographic characteristics, history of measles and vaccine immunization were investigated by questionnaire. 5 ml blood sample of each subject was collected, and the Measles IgG antibody was measured by ELISA assay. RESULTS: Positive rate of measles antibody was 84.71% (1800/2125) and standardized positive rate was 88.07% . Median of antibody was 960.46 IU/L. Positive rate and median of measles antibody were significantly different between population from different age groups (χ(2) = 341.60, P < 0.01; H = 216.27, P < 0.01). Antibody positive rate and median were lowest in the <1 year age group, which were separately 43.06% (90/209) and 185.80 IU/L; and highest in the 1-4 (97.31% (181/186) and 2448.81 IU/L) and 5-9 years age group (96.46% (218/226) and 1910.72 IU/L). The range of antibody positive rate and median in adults of ≥ 15 years were 81.98%-90.14% and 744.38-1474.84 IU/L. Antibody positive rate and median in persistent population, which were separately 82.45% (883/1071) and 899.82 IU/L, were lower than those in migrant population, which were 87.00% (917/1054) and 166.19 IU/L, respectively (χ(2) = 8.51, P < 0.01;U = 538 704.00, P < 0.01). Antibody positive rate and median in population with vaccination history, which were separately 91.95% (891/969) and 1443.11 IU/L, were higher than those population without vaccination history and people whose history unknown (32.95% (57/173) , 127.33 IU/L; 86.67% (852/983) , 923.73 IU/L). The difference showed statistical significance (χ(2) = 399.92, P < 0.01; H = 202.11, P < 0.01). CONCLUSION: Among the persistent population in China, measles antibody level among the children aging 1-9 years old was high enough to prevent outbreak and epidemic of measles. However, we should try our best to strengthen the measles antibody level among the babies younger than 1 year old and the migrant population aging between 15 and 40 years old.

The incidence of herpes zoster in China: A meta-analysis and evidence quality assessment.

This review aimed to estimate the disease burden of herpes zoster (HZ) in China and explore the application of the Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) approach in studies of disease burden. We searched for the literature of observational studies analyzing HZ incidence in populations of all ages in China. Meta-analysis models were constructed to calculate the pooled incidence of HZ and pooled risks of postherpetic neuralgia (PHN), HZ recurrence, and hospitalization. Subgroup analysis was performed according to gender, age, and quality assessment score. The quality of evidence for incidence was rated using the GRADE system. Twelve studies with a total of 25,928,408 participants were included in this review. The pooled incidence for all ages was 4.28/1000 person years (95% CI 1.22-7.35). It increased with the increasing in age especially for individuals aged ≥60 y, which was 11.69/1000 person years (95% CI 6.56-16.81). The pooled risks of PHN, recurrence, and hospitalization were 12.6% (95% CI 10.1-15.1), 9.7% (95% CI 3.2-16.2), and 6.0/100,000 population (95% CI 2.3-14.2), respectively. The quality of the evidence assessment of the pooled incidence by the GRADE for all ages was 'low'; however, it was 'moderate' for the ≥60 yold subgroup. HZ is a serious public health problem in China and is more significant in individuals older than 60 y. Therefore, an immunization strategy for the zoster vaccine should be considered. The evidence quality assessment by the GRADE approach indicated that we had more confidence in the estimation of aged population.

Impact of herpes zoster and post-herpetic neuralgia on health-related quality of life in Miyun District of Beijing, China: An EQ-5D survey.

Background: Herpes zoster (HZ) and post-herpetic neuralgia (PHN) cause considerable morbidity, especially in elderly adults, but the burden is under-recognized in mainland China. Methods: We conducted a case registry and follow-up study of HZ in Miyun District, Beijing from January 1, 2017 through December 31, 2018. Registered HZ cases were followed-up for pain to 365 days. The first 50 patients with HZ in each age group (≤14, 15-29, 30-39, 40-49, 50-59, 60- 69, 70-79, ≥80 years) and all those with PHN completed the EuroQoL five dimensions questionnaire (EQ-5D) to evaluate health-related quality of life (HRQoL) in patients with HZ and PHN. Ratings using the EQ-5D dimensions, visual analogue scale (VAS), health utility score (HUS) and quality-adjusted life years (QALYs) lost were compared among age groups. Results: In total, 2008 patients with HZ were followed for a median 22 days (interquartile range[IQR] = 20-90), with an estimated incidence of 4.39 per 1000 person-years. We identified 122 (6.08 %) PHN cases. The median age of patients with PHN (65 years, IQR = 55-71) was older than that of patients with HZ (54 years, IQR = 43-64) (P < 0.001). The median duration of pain was 170 days (IQR = 144-355.5) for PHN and 15 days (IQR = 9-25) for HZ. All 95 patients with PHN and 319 sampled patients with HZ completed the EQ-5D survey. The median QALY loss of HZ increased from 0.004 (IQR = 0.001-0.02) in patients 50-59 years old to 0.02 (IQR = 0.01-0.06) in those ≥ 80 years old (P < 0.01). After weighting for age, the mean QALY loss per HZ case was estimated at 0.02 (standard deviation [SD] 0.04). The mean QALY loss per PHN case was 0.13 years (SD 0.12). Conclusions: HZ and PHN caused a substantial burden, especially among adults aged ≥ 50 years in Miyun District, Beijing, China. Vaccination should be considered to alleviate the burden of this painful disease.

Molecular surveillance of rubella virus in Beijing, China during 2010-2021: Progress and challenges in rubella elimination.

Rubella is listed by the World Health Organization (WHO) as a disease that needs to be eliminated worldwide. The aim of this study was to understand the progress and challenges towards rubella elimination in Beijing, China, by analyzing molecular surveillance data combined with immunization and surveillance strategies as well as epidemiological data. With high immunization coverage under the 3-dose policy (8 months, 18 months, and 6 years) and supplementary immunization activities for the floating population, rubella incidence showed a downward trend since 2010, despite two epidemics that occurred in 2014-2015 and 2019. The reported rubella cases were generally concentrated in the age group of 15-34 years. Although citywide surveillance for congenital rubella syndrome (CRS) has been carried out since 2016, only one case has been confirmed by laboratory testing. Furthermore, molecular surveillance data showed that rubella viruses (RVs) circulating in Beijing during 2010-2020 were evidently heterogeneous; the domestic lineage 1E-L1 and multiple imported lineages, including 2B-L1, 1E-L2, and 2B-L2c, were identified in the last decade. Meanwhile, two lineage-related switches were determined, including the displacement of lineage 1E-L1 with lineage 2B-L1 around 2014 and the transition between lineage 2B-L1 and lineage 1E-L2 and 2B-L2c in 2018-2019. This RV transmission pattern was similar to that observed across the country, whereas lineages 1E-L1 and 2B-L2c were prevalent in Beijing for a shorter period. Overall, these results indicate the need to maintain routine immunization with rubella-containing vaccines, promote regular supplementaryimmunizationactivities, and enhance rubella and CRS surveillance even in order to accelerate rubella elimination in Beijing. Further, the existing immunization strategies must be optimized to further close the immunity gap.

Factors associated with utilization of a free HIV VCT clinic by female sex workers in Jinan City, Northern China.

Based on our previous qualitative exploration, this research presents the second phase in our study of factors associated with utilization of a free HIV VCT clinic in Jinan City, Northern China, by female sex workers (FSWs). A total of 970 FSWs from entertainment venues were interviewed and prospectively followed to determine who ultimately sought and received VCT at the clinic, compared to those who did not. Simple and multiple logistic regressions were performed on factors drawn from the Ecological Perspective, hypothesized to be associated with utilization of testing at the VCT clinic. Despite 69% of FSWs expressing willingness to attend the VCT clinic, only 11% were actually tested. The multiple logistic regression model that provided best goodness of fit included the covariates of willingness to attend the VCT clinic (Adjusted OR 3.13, 95% CI: 1.62-6.59), low perceived HIV infection risk (Adjusted OR 0.64, 95% CI: 0.35-1.11), low fear of FSWs status disclosure in the clinic (Adjusted OR 0.55, 95% CI: 0.31-0.94) and influence of acquaintances (Adjusted OR 0.52, 95% CI: 0.29-0.89) and peers (Adjusted OR 2.45, 95% CI: 1.40-4.50). This is the first study in China to follow FSWs longitudinally to measure factors related to VCT utilization. The low utilization of VCT services by participants in our study is similar to prior reports throughout China. FSWs' access to VCT service is associated with intrapersonal, institutional, and particularly, interpersonal factors. Based on these findings, we recommend emphasis on confidentiality of services, VCT education for influential peers, and introduction of HIV rapid testing on site.

Effect of Earlier Vaccination and a Two-Dose Varicella Vaccine Schedule on Varicella Incidence - Beijing Municipality, 2007-2018.

WHAT IS ALREADY KNOWN ABOUT THIS TOPIC?: The World Health Organization (WHO) varicella vaccines position paper states that countries where varicella is an important public health burden could consider introducing varicella vaccine (VarV) in the routine childhood immunization program (1). VarV has been available for many years in China but is not included in most routine immunization programs in China. As a result, substantial heterogeneity in vaccination coverage exists across regions. WHAT IS ADDED BY THIS REPORT?: In Beijing, adding a second dose of VarV for children and increasing coverage reduced the incidence of varicella. Lowering the age of the first dose of VarV to 12 months could further reduce varicella, especially among toddlers. WHAT ARE THE IMPLICATIONS FOR PUBLIC HEALTH PRACTICE?: Governments should use economic analysis to consider inclusion of VarV into the routine children immunization program as a free vaccine and adopting a 2-dose schedule that starts at 12 months of age.

Seroepidemiology of pertussis in China: A population-based, cross-sectional study.

BACKGROUND: Despite high pertussis vaccination coverage and significant decrease of pertussis since the adoption of the Expanded Programme on Immunization (1978), increased pertussis incidence has been reported in China from 2013 to 2017. This study aimed at evaluating the immune response to pertussis among vaccinated children and beyond in China. METHODS: The study recruited 2 144 healthy subjects. Serum IgG antibodies against pertussis toxin (anti-PT IgG) were measured by ELISA. Anti-PT IgG concentration (GMC), seropositivity rate (GMC ≥ 40 IU/ml), and recent infection rate (GMC > 100 IU/ml) were calculated. Participants ≤ 2 years-old were further stratified by vaccination schedule intervals and participants ≤ 6 years-old by vaccine used (Domestic DTaP or DTaP-IPV//PRP ~ T (Pentaxim, SP)). RESULTS: Among 0-6-year-olds, the anti-PT IgG GMC was 5.99 IU/ml (95%CI 5.39-6.67). The GMC increased in accordance with the primary vaccination series (4-6 months) and the toddler booster (18-23 months), and continuously declined thereafter to its nadir at 6 years-old [3.72 IU/ml (95%CI 2.91-4.77)]. GMCs were markedly higher in those vaccinated with DTaP-IPV/PRP ~ T compared to DTaP. In individuals > 6 years-old, the GMC was 5.67 IU/ml (95%CI 5.36-6.00), the seropositivity rate was 6.7% (95%CI 5.5-7.9) and the recent infection rate was 1.2% (95%CI 0.7-1.7). The seropositivity rates increased from 6 years-old and peaked at 9 years-old (10.3% [95%CI 0.7-19.8]). CONCLUSIONS: Vaccination against pertussis increases anti-PT IgG, but wanes over time. The sero-estimated infection rates increase from school age and peak at about 9 years-old. These results support the addition of a booster of pertussis vaccine at preschool age.

Reported willingness and associated factors related to utilization of voluntary counseling and testing services by female sex workers in Shandong Province, China.

OBJECTIVE: To explore reported willingness and factors associated with utilization of voluntary counseling and testing services by female sex workers (FSWs) in China and to offer recommendations to optimize use of such services. METHODS: A questionnaire to explore willingness to use VCT was designed based on social ecological theory and formative qualitative research. A cross-sectional survey was conducted among FSWs from entertainment venues. Single and multiple logistic regression analyses were employed to examine factors associated with reported willingness to utilize VCT. RESULTS: A total of 970 FSWs provided valid questionnaires, with 69% (669) expressing willingness to utilize VCT. Factors at the interpersonal level associated with reported willingness included knowledge about VCT, desire to get help if diagnosed as HIV positive, ability to imagine life after an HIV positive diagnosis, and perceived support for VCT from peers, managers, and family members. Availability of free antiretroviral (ARV) treatment represented a factor at policy level. Other factors included intention to leave sex work in the near future, having had a previous HIV test, and lack of a suspected STD history. CONCLUSIONS: The rate of reported willingness to use VCT among FSWs was substantially higher than that of actual VCT utilization (11%). The next step is to explore the connection between reported willingness and actual use. Based on these findings, peer education, VCT knowledge dissemination, and free ARV treatment should be emphasized to increase FSWs' willingness to use VCT.

Outbreak of measles among persons with secondary vaccine failure, China, 2018.

Although the incidence of measles has been dramatically reduced by the highly effective measles vaccine, cases of measles and outbreaks continue to occur in vaccinated population because of immunization failure. We report on an outbreak in which two cases had previous evidence of measles immunity and then one of them transmitted measles infection to an unvaccinated contact. The cases and contacts exposed during the outbreak were investigated. Clinical information and epidemiological information were obtained. Serum samples were collected for measles-specific immunoglobulin M (IgM), immunoglobulin G (IgG) and IgG avidity. Throat swabs were obtained to test for measles virus RNA. Two measles cases (case 1 and case 2) who have received one dose of MCV in past 5 years, and both working at a hospital in Beijing, occurred in 18th and 20nd of January, respectively. Out of the 102 contacts, one additional case (case 3) who had a close, long-term co-exposure with case 1 was reported subsequently. No additional cases of measles occurred among 15 contacts of case 3. The index case was not ascertained through the outbreak review. All three cases had laboratory confirmation of measles infection. Both case 1 and case 2 had high-avidity IgG antibody characteristic of a secondary immune response and developed a modified clinical presentation. This report confirms that a vaccinated individual with documented secondary vaccine failure (SVF) could transmit measles and is the second report since a New York City outbreak (the first report in China). The outbreak represented a series of rare events, so we can conclude that the SVF individuals in the transmission chain of measles are unlikely to threaten measles elimination. The importance of the herd immunity in preventing transmission and sensitive surveillance activities in case of misdiagnosis is emphasized.

Mumps disease in Beijing in the era of two-dose vaccination policy, 2005-2016.

BACKGROUND: Since the introduction of mumps-containing vaccines (MuCV) in 1995 in Beijing, two-dose MuCV vaccination policy has been used, with the 1st and 2nd doses given at 18 months and 6 years of age, respectively. METHODS: Mumps epidemiology during 2005-2016 was described using surveillance data. Vaccine effectiveness (VE) of MuCV against disease was estimated for cases born during 2002-2009 and reported in 2016. VE against complications was estimated for all cases. MuCV coverage was estimated for children born during 1999-2015 using data from Beijing Immunization Information System. RESULTS: Overall mumps incidence decreased from 30.38/100,000 persons in 2005 to 10.26/100,000 persons in 2016. Incidence declines in children aged <15 years. No significant incidence change occurred in adults aged ≥20 years. Incidence in persons aged 15-19 years increased by 132.73% in 2012 when compared with in 2005. Rates of meningitis/encephalitis, orchitis, and other complications among cases decreased during 2005-2016. The majority (97%) of outbreaks occurred in schools. Total number of outbreaks and average outbreak size decreased during 2005-2016. Among outbreak-related cases, 69.54%, 29.67% and 0.79% had received 0 dose, 1dose and 2 doses of MuCV, respectively. Coverage of the 1st MuCV dose at 2-5 years of age increased by 42.75% during 2005-2016. Coverage of the 2nd MuCV dose at 6-14 years of age increased by 12.87% during 2013-2016. Overall VE estimates of MuCV against mumps disease were 74.51% (95% CI: 65.57-81.34%) for 1 dose and 83.16% (95% CI: 78.60-86.31%) for 2 doses. Both VE estimates increased by birth cohorts. VE estimate against complications for 2-dose MuCV was higher than for 1 dose. CONCLUSIONS: Increasing MuCV coverage achieved declining mumps incidence and complication rate. Current epidemiology supported 2-dose MuCV vaccination policy. The incidence rise in persons aged 15-19 years in 2012 and waning immunity for the 2nd MuCV dose merited close follow-up.