The optimal interval for post-vaccination serological test in infants born to mothers with positive hepatitis B surface antigen
Hongyu Huang, Xuhui Zhang, Yuqian Luo, Jie Chen, Jing Feng, Yimin Dai, Yali Hu, Yi‐Hua Zhou
Abstract
Postvaccination serologic testing (PVST) is utilized to monitor the success or failure of vaccination against hepatitis B virus (HBV) infection in infants of hepatitis B surface antigen (HBsAg) positive mothers. This secondary analysis of 1255 infants of HBsAg-positive mothers at 7–14 months age included in two prospective studies aimed to determine the optimal interval for PVST after three hepatitis B vaccine doses. HBsAg and anti-HBs were quantitatively tested with microparticle enzyme immunoassay. The average PVST interval was 3.8 ± 2.2 months. Overall, 1.7% (21/1255) infants had anti-HBs <10 mIU/mL. The non-response rates were 1.6%, 1.1%, 0.9%, 0.7%, 1.1%, 0.7%, and 5.7% when PVST was performed at an interval of 1, 2, 3, 4, 5, 6, and 7–8 months after the third vaccine dose, respectively. Compared with 1 month of PVST interval, the non-response rate in infants who underwent PVST 7–8 months was significantly higher (χ2 = 4.616, P = .032). Anti-HBs titers were significantly declined in infants with medium responses when PVST was performed with longer intervals (χ2 = 27.592, P < .001), actually declined from interval of 6, and 7–8 months (Z = −3.177, P = .001 and Z = −3.715, P < .001), respectively. These results indicate that PVST may be performed at the age of 7–12 months for infants vaccinated on 0, 1, and 6-month schedule. To identify non-responders as early as possible, we suggest that PVST is performed at 7 months age or 1 month after the final vaccine dose.