Uzbekistan, a highly endemic country for hepatitis B virus (HBV), introduced infant vaccination with hepatitis B vaccine (HepB) in 2001. Since 2002, it had â„90% reported immunization coverage for â„3 doses of HepB (HepB3) and the birth dose (HepB-BD). However, the impact of HepB vaccination and the progress towards achieving the regional hepatitis B control and global viral hepatitis B elimination goals had not been assessed. To determine current HBsAg prevalence among children in Uzbekistan, in 2022, we conducted a nationwide serosurvey among schoolchildren (grades 1-3) using a stratified, multi-stage cluster design. Participants' basic demographics and HepB immunization information were obtained. Blood specimens were tested for HBsAg using a WHO-prequalified rapid test (Bioline HBsAg WB, Abbott Diagnostics). Samples with positive and indeterminate results were tested for HBsAg by ELISA (Murex HBsAg Version3, Diasorine). Weighted proportions and adjusted 95% confidence intervals (CI) were calculated. Of 4119 children enrolled in 148 schools, blood was collected from 3753 (91.1%) and immunization data were available for 3833 (93.3%). National HBsAg prevalence was 0.20% (adjusted 95% CI, 0.09%-0.38%). Among children with available immunization data, 97.7% (97.2%-98.1%) received â„3 HepB doses and 94.9% (94.1%-95.5%) received HepB-BD, including timely HepB-BD in 93.7% (92.9%-94.5%). The survey demonstrated that Uzbekistan has met the <0.5% European regional HBsAg seroprevalence target and has made substantial progress towards meeting the <0.1% HBsAg seroprevalence target for the elimination of HBV mother to-child transmission (MTCT). Based on these findings andâ„90% HepB-BD and HepB3 coverage, in 2023, Uzbekistan was validated as having achieved the regional hepatitis B control goal. To achieve the elimination of MTCT of HBV, additional interventions, including improving antenatal screening for HBsAg, providing antiviral treatment of eligible HBsAg-positive pregnant women and hepatitis B immunoglobulin to infants born to HBsAg-positive mothers, should be considered.
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