RESUMEN
In 2006, 2014 and 2020, the positive rates of HBsAg in 560, 384 and 402 children aged 1 to 14 years were 4.5%, 2.6% and 2.5%, respectively, with no statistically significant differences (P>0.05). The positive rate of anti-HBs was highest in 2014 (57.8%) and lowest in 2006 (34.1%) (P<0.05). The positive rate of anti-HBc was highest in 2006 (15.7%), and decreased in 2014 (7.8%) and 2020 (5.7%) (P<0.001). The timely rate of the first dose of hepatitis B vaccine for children in Lhasa in 2006, 2014 and 2020 was 7.7% (43/560), 50.3% (193/384) and 94.8% (381/402), respectively. The overall vaccination rates were 15.4% (86/560), 35.2% (135/384) and 96.0% (386/402), respectively, showing a trend of gradual increases (χtrend values were 718.63 and 589.59, both P values<0.001).