{'fraction_non_alphanumeric': 0.0397170837867247, 'fraction_numerical': 0.017954298150163223, 'mean_word_length': 4.990228013029316, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Hepatitis B infection, seroprotection, and anamnestic response among children vaccinated during infancy in Beni-Suef, Egypt

ObjectivesThe aims of this study were to evaluate the long-term seroprotection after hepatitis B virus (HBV) vaccination and to assess the need for a booster dose among children vaccinated during infancy. Patients and methodsA cross-sectional study was carried out in two areas in the Beni-Suef governorate (El-Wasta city and Blevia village) using a multistage random sampling. Face-to-face interviews of 362 children and their parents were carried out. Blood samples were collected to assess hepatitis B surface antigen (HBsAg), total hepatitis B core antibody (anti-HBc), and antibodies to hepatitis B surface antigen (anti-HBs) using ELISA. Positive samples for HBsAg/anti-HBc were subjected to quantitative HBV-DNA detection by a real-time PCR. Children with HBV non-sero-protection received a booster dose of the HBV vaccine to assess their anamnestic response 4 weeks later. ResultsFour (1.1%) of the participants had evidence of breakthrough HBV infection and the seroprotection rate was 57%. On multivariate analysis, the risk of non-sero-protection was significantly higher among children aged 5to less than 10 years, 10 to less than 15, and at least 15 years compared with younger children [adjusted odds ratio (AOR)=5.2, 18.6, and 19.7, respectively] and those living in rural compared with urban areas (AOR=2.1). Out of 117 children with non-sero-protective levels, 86.3% developed an anamnestic response after a booster dose. ConclusionLong-term HBV immunity exists among children vaccinated during infancy even in case of reduced or absent anti-HBs over time. The high anamnestic response rate developed signifies the presence of immune memory and indicates that there is no need for a booster dose.