title: The epidemiology and risk factors for breakthrough varicella in Beijing Fengtai district.
abstract: Using data from the Immunization Information System (IIS) and the Infectious Disease Reporting System (IDRS), we have described the epidemiology and analyzed the risk factors for breakthrough varicella in the Fengtai district of Beijing, China. From 2008 to 2011 the breakthrough varicella infection rate (BVR) was 0.65%, 0.85%, 1.08% and 1.56% respectively, thus demonstrating a distinct increasing tendency (P<0.001). We also compared the incidence of varicella-related illnesses between the breakthrough varicella cases and unvaccinated cases, and found that the severity of illness in the breakthrough cases was milder than that of unvaccinated cases. Moderate-to-severe cases (P=0.008, OR=0.676, 95% CI=0.505-0.904) were differently distributed in the breakthrough varicella cases and unvaccinated cases. In this study, we demonstrated that floating status (P=0.031, OR=1.96, 95% CI=1.06-3.62), contact history (P<0.001, OR=2.67, 95% CI=1.59-4.69), time since vaccination (P=0.006, OR=1.59, 95% CI=1.14-2.21), age at vaccination (P=0.010, OR=0.59, 95% CI=0.39-0.88) and combined vaccination (P=0.026, OR=3.99, 95% CI=1.18-13.54) were associated with the occurrence of breakthrough varicella, and among these, floating status is a novel risk factor. This study should provide useful information for the evaluation of the performance of varicella vaccination and prevention in PR China.
authors.affiliation: Department of Epidemiology and Biostatistics, School of Public Health and Family Medicine, Capital Medical University, Beijing 100069, PR China.
authors.forename: Xue
authors.initials: X
authors.lastname: Zhang
authors.forename: Yuxiang
authors.initials: Y
authors.lastname: Yan
authors.forename: Fen
authors.initials: F
authors.lastname: Liu
authors.forename: Yanxia
authors.initials: Y
authors.lastname: Luo
authors.forename: Jie
authors.initials: J
authors.lastname: Zhang
authors.forename: Xiaoxia
authors.initials: X
authors.lastname: Peng
authors.forename: Yuxiang
authors.initials: Y
authors.lastname: Zhang
authors.forename: Shujing
authors.initials: S
authors.lastname: Han
authors.forename: Jianzhong
authors.initials: J
authors.lastname: Zhao
authors.forename: Yan
authors.initials: Y
authors.lastname: He
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D002644:Chickenpox / Q000453:epidemiology*; D019433:Chickenpox Vaccine; D002648:Child; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D018563:Disease Notification; D054242:Emigrants and Immigrants; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D008297:Male; D012307:Risk Factors; D012720:Severity of Illness Index; D017678:Sex Distribution; D014611:Vaccination / Q000706:statistics & numerical data*; D055815:Young Adult
chemical_list: D019433:Chickenpox Vaccine