RESUMEN
Objective: To evaluate the effectiveness of hepatitis B prevention and control in Tibet Autonomous Region by comparative analysis of the results of seroepidemiological surveys of hepatitis B in 2014 and 2020. Methods: The required sample size was calculated based on the estimated HBsAg positivity rates of permanent residents aged 1-4, 5-14, 15-29, and 30-69 years. A total of 7 163 people and 4 802 people were required in 2014 and 2020, respectively. The subjects were selected by stratified multistage cluster random sampling method, using questionnaires to obtain basic information, and 5 ml of venous blood was collected from each subject to detect HBsAg, anti-HBs, and anti-HBc, and rechecked the HBsAg positive samples. SPSS 22.0 software was used to analyze the survey results, calculate the positive rate and 95% confidence interval. Results: A total of 7 069 people were investigated in 2014 and 4 913 people in 2020. In 2020, the positive rate of HBsAg, anti-HBs, and anti-HBc was 9.20% (452/4 913), 37.11% (1 823/4 913), and 32.75% (1 609/4 913), respectively, and decreased by 22.95%, 15.54%, and 1.92% as compared with the rate in 2014. The positive rate of HBsAg of people aged 1-, 5-, 15- and 30-69 years in 2020 was 2.23% (8/358), 2.85% (20/701), 6.86% (69/1 006) and 12.46%(355/2 848), respectively, decreased by 61.82%, 62.75%, 54.81% and 24.21% as compared with the rate in 2014. The positive rate of anti-HBs of people aged 1-4 years was 52.79% (189/358), 10.30% increased compared with 2014; for people aged 5-, 15-, and 30-69 years was 32.67% (229/701), 37.67% (379/1 006) and 36.03%(1 026/2 848), respectively, decreased by 20.84%, 14.13% and 16.52% as compared with the rate in 2014. The positive rate of anti-HBc of people aged 1-, 5-, 15-, 30-69 years was 4.19% (15/358), 6.42%(45/701), 21.07% (212/1 006), and 46.95% (1 337/2 848), respectively, decreased by 59.63%, 58.93%, 50.49%, and 12.10% as compared with the rate in 2014. Conclusions: The prevention and control of hepatitis B in Tibet have made partial achievements. The prevalence of HBsAg among people aged 1-69 years in 2020 had declined compared with 2014, but it is still at a high epidemic level. People have a high risk of HBV infection for a low level of anti-HBs. It is necessary to strengthen the vaccination of hepatitis B further and effectively implement the strategy of blocking mothers and children of the hepatitis B virus.