LAUSR

Objective: To evaluate the epidemiological characteristics of the children aged 1-4 years without timely birth dose of hepatitis B vaccine (HepB(1)) vaccination. Methods: Based on the data from 160 disease surveillance points in 31 provinces of China, two-stage cluster random sampling was used to select the target population aged 1-4 years. A standard questionnaire was used to collect the information about the birth date, gender, ethnic group, place of birth, HepB immunization history of the children selected. A blood sample (3 ml) was taken from each subject for HBsAg testing. SAS software (Version 9.4) was used in our study. We analyzed the age, gender, ethnic group, area specific distributions of the children aged 1-4 years without timely HepB(1) vaccination and the influencing factors, and the relationship between the HepB(1) vaccination time and HBsAg prevalence rate. Results: A total of 12 587 children aged 1-4 years were analyzed and the non-timely HepB(1) vaccination rate was 10.12%. The place of birth, ethnic group, urban/rural area, eastern/central/western area, age were the main influencing factor of the non-timely HepB(1) vaccination. The non-timely HepB(1) vaccination rate was higher in 3-4 years old children (11.13%) than in 1-2 years old children (8.97%), in rural area (12.05%) than in urban area (8.19%), in western area (13.41%) than in central area (9.27%) and eastern area (7.72%), in minority ethnic group (18.06%) than in Han ethnic group (8.77%) and in children born outside hospital (57.66%) than in children born in hospital (9.27%). The HBsAg prevalence rate among 1-4 years children was 0.31%. The HBsAg prevalence rate of the children with timely HepB(1) vaccination (0.25%) was lower than that of the children without timely HepB(1) vaccination (0.89%). Conclusions: In China, the HBsAg prevalence rate among 1-4 years children with HepB vaccination decreased to <0.5% and the timely HepB(1) vaccination rate reached to 90%. We should strengthen the timely HepB(1) vaccination for the children in minority ethnic groups, in western area, in rural area as well as those born outside hospitals.