Anti-HBV type ad, ay Surface Antigen Polyclonal antibody

The Western Pacific Region (WPR) established a goal to decrease chronic hepatitis B virus (HBV) infection among children to <1% and to achieve >= 95% hepatitis B vaccine birth dose (HepB-BD) and >= 95% three-dose (HepB3) coverage by 2017. In 2016, we conducted a national serosurvey in the Solomon Islands among 6-7-year-old school children to assess progress towards the control goal and immunity to measles, rubella, tetanus and diphtheria. Eighty schools were selected systematically proportional to their 6-7-year-old population; all 6-7-year-olds were enrolled. We collected basic demographic information and vaccination history. Children were tested for HBV surface antigen (HBsAg) using a rapid test, and for immunity to measles, rubella, tetanus, and diphtheria using a multiplex bead assay. In total, 1,249 out of 1,492 children (84%) were enrolled, among whom 1,169 (94%) underwent HBsAg testing and 1,156 (93%) provided dried blood spots. Almost 80% (n = 982) of enrolled children had vaccination cards, among whom 59% (n = 584) received a timely HepB-BD (within 24 hours of birth), 95% (n = 932) received HepB3, and >90% received vaccines for diphtheria, tetanus, and measles (rubella vaccine was not available at the time). HBsAg prevalence was 3.1% (95% confidence interval (CI): 2.0%-4.9%), with 55% of identified cases from one province. Among 982 children with vaccination cards, HBsAg prevalence was higher among children who had not received a timely HepB-BD and at least two HepB doses compared to those who had (4% vs. 2%). Of 1,156 tested children, immunoprotection estimates were 99% (95% CI: 98%-99%) for measles, 99% (95% CI: 97%-100%) for rubella, 85% (95% CI: 83%-87%) for tetanus, and 51% (95% CI: 47%-55%) for diphtheria. Improving timely HepB-BD coverage and maintaining high HepB3 coverage could help Solomon Islands reach the regional HBV control goal. Low immunity to tetanus and diphtheria suggests the need to introduce booster doses to ensure long-term protection. Published by Elsevier Ltd.

Herein, a novel sandwich-type electrochemical immunosensor was fabricated based on Fe3O4 nanoflowers (Fe3O4 NFs) and heterogeneous chain reaction (HCR) signal amplification strategy for the sensitive detection of hepatitis B surface antigen (HBsAg). The aldehyde-functionalized Fe3O4 NFs are used as a supporting matrix to immobilize the hepatitis B surface antibody 1 (HBsAb1). The biotin-modified single-strand DNA (biotin-SO) was connected onto the biotin-HBsAb2 via linkage of streptavidin (SA), followed by addition of methylene blue (MB) modified single strand DNA1 (MB-S1) and DNA2 (MB-S2) for HCR signal amplification. The designed immunosensor exhibited a detection linear range of 0.5 pg mL(-1)-0.25 ng mL(-1) and a low detection limit of 0.16 pg mL(-1), with excellent stability, selectivity and reproducibility. Furthermore, HBsAg is detected in the serum samples with a stable and fast response, indicating that the proposed immunosensor has a promising potential application in clinical analysis.