Sui Zhu1, Fangfang Zeng2, Lan Xia3, Hong He4, Juying Zhang5. 1. Department of Epidemiology and Biostatistics, School of Public Health, Sichuan University, Chengdu, Sichuan, China. 2. Department of Epidemiology, School of Basic Medical Sciences, Jinan University, Guangzhou, Guangdong, China; Key Laboratory of Food, Nutrition and Health, School of Public Health, Sun Yat-sen University, Guangzhou, Guangdong, China. 3. Sichuan Provincial Center for Disease Control and Prevention, Chengdu, Sichuan, China. 4. Health Care and Physical Examination Center, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China. 5. Department of Epidemiology and Biostatistics, School of Public Health, Sichuan University, Chengdu, Sichuan, China. Electronic address: juying109@163.com.
Abstract
BACKGROUND: Although extensive varicella vaccination coverage has been reported in many countries, breakthrough varicella (BV) still occurs in healthy children. We performed a meta-analysis to understand whether 2 varicella vaccine doses are needed in children and, if so, to determine the best time to vaccinate. METHODS: The BV incidence rates after 1 or 2 doses of varicella vaccine were pooled using random effects, and 95% confidence intervals (CI) were used to estimate the risk factors after vaccination. RESULTS: A total of 27 original articles were included in this meta-analysis. The pooled average BV incidence rate in children vaccinated with 1 dose was 8.5 cases per 1,000 person years (PY) (95% confidence interval [CI], 5.3-13.7; random effects model) and 2.2 cases per 1,000 PY (95% CI, 0.5-9.3; random effects model) in children vaccinated with 2 doses. The pooled trend of the annual BV incidence rate from the first to eighth year fluctuated, with a peak annual incidence rate of 35.3 cases per 1,000 population in the fourth year. The meta-regression showed that design type, type of vaccine, and their interaction accounted for approximately 71.74% of the heterogeneity in the average BV incidence rate after 1 vaccine dose. CONCLUSIONS: Two doses of varicella vaccine are more effective than a single dose, and 3-4 years between the first and second vaccinations may achieve higher efficacy.
BACKGROUND: Although extensive varicella vaccination coverage has been reported in many countries, breakthrough varicella (BV) still occurs in healthy children. We performed a meta-analysis to understand whether 2 varicella vaccine doses are needed in children and, if so, to determine the best time to vaccinate. METHODS: The BV incidence rates after 1 or 2 doses of varicella vaccine were pooled using random effects, and 95% confidence intervals (CI) were used to estimate the risk factors after vaccination. RESULTS: A total of 27 original articles were included in this meta-analysis. The pooled average BV incidence rate in children vaccinated with 1 dose was 8.5 cases per 1,000 person years (PY) (95% confidence interval [CI], 5.3-13.7; random effects model) and 2.2 cases per 1,000 PY (95% CI, 0.5-9.3; random effects model) in children vaccinated with 2 doses. The pooled trend of the annual BV incidence rate from the first to eighth year fluctuated, with a peak annual incidence rate of 35.3 cases per 1,000 population in the fourth year. The meta-regression showed that design type, type of vaccine, and their interaction accounted for approximately 71.74% of the heterogeneity in the average BV incidence rate after 1 vaccine dose. CONCLUSIONS: Two doses of varicella vaccine are more effective than a single dose, and 3-4 years between the first and second vaccinations may achieve higher efficacy.
Authors: Hua Zhu; Han Zhao; Rong Ou; Qing Zeng; Ling Hu; Hongfang Qiu; Manoj Sharma; Mengliang Ye Journal: Int J Environ Res Public Health Date: 2020-01-20 Impact factor: 3.390