Prevalence of chronic hepatitis B virus infection before and after implementation of a hepatitis B vaccination program among children in Nepal

Abstract

Background In Nepal, an estimated 2–4% of the population has chronic hepatitis B virus (HBV) infection. To combat this problem, from 2002–2004, a national three dose hepatitis B vaccination program was implemented to decrease infection rates among children. The program does not currently include a birth dose to prevent perinatal HBV transmission. In 2012, to assess the impact of the program, we conducted a serosurvey among children born before and after vaccine introduction. Methods In 2012, a cross-sectional nationally representative stratified cluster survey was conducted to estimate hepatitis B surface antigen (HBsAg) prevalence among children born from 2006 to 2007 (post-vaccine cohort) and among children born from 2000 to 2002 (pre-vaccine cohort). Demographic data, as well as written and oral vaccination history were collected. All children were tested for HBsAg; mothers of HBsAg positive children were also tested. Furthermore, we evaluated the field sensitivity and specificity of the SD Bioline HBsAg rapid diagnostic test by comparing results with an enzyme immunoassay. Results Among 2181 post-vaccination cohort children with vaccination data by either card or recall, 86% (95% Confidence Interval [CI] 77–95%) received ≥3 hepatitis B vaccine doses. Of 1200 children born in the pre-vaccination cohort, 0.28% (95% CI 0.09–0.85%) were positive for HBsAg; of 2187 children born in the post-vaccination cohort, 0.13% (95% CI 0.04–0.39%) were positive for HBsAg (p=0.39). Of the 6 children who tested positive for HBsAg, 2 had mothers who were positive for HBsAg. Finally, we found the SD Bioline HBsAg rapid diagnostic test to have a sensitivity of 100% and a specificity of 100%. Conclusions This is the first nationally representative hepatitis B serosurvey conducted in Nepal. Overall, a low burden of chronic HBV infection was found in children born in both the pre and post-vaccination cohorts. Current vaccination strategies should be continued.

Diagnostic accuracy of tests to detect hepatitis B surface antigen: a systematic review of the literature and meta-analysis

“…The reference standards used were CMIA in 5 studies, MEIA in 3 studies, and EIA/ELISA in 25 studies, with 3 studies using more than one type of reference assay. Test evaluations were conducted in 23 countries: six studies were conducted in high-income country studies [ 23 , 27 , 29 , 32 , 38 , 42 ], two in upper-middle income country studies [ 14 , 34 ], nine in lower-middle income [ 21 , 24 , 28 , 30 , 31 , 33 , 35 , 39 , 47 ], and six in low income [ 18 , 20 , 22 , 40 , 43 , 46 ] countries, with income levels classified according to the World Bank ranking criteria. The overall pooled sensitivity and specificity were 90.0% (95% CI: 89.1, 90.8) and 99.5% (95% CI: 99.4, 99.5), respectively.…”

“…Strengths of this review include evaluation of a comprehensive evidence base, use of a pre-specified protocol incorporating numerous major scientific databases, and assessment of additional areas relevant to HBsAg diagnostic testing, notably comparison with NAT and potential impact of occult hepatitis B. We identified 11 additional articles [ 18 , 22 , 25 , 28 , 29 , 35 , 37 , 43 , 45 – 47 ] not found in the most recent systematic review assessing the diagnostic accuracy of RDTs [ 11 ]. The pooled sensitivity for RDTs in this review is lower than reported in previous systematic reviews (pooled sensitivities of 97.1% [ 11 ], 94.8% [ 10 ], and 98.1% [ 9 ]).…”

Occupational Hepatitis B Exposure: A Peek into Indian Dental Students’ Knowledge, Opinion, and Preventive Practices

“…The protective efficacy of vaccine is well established [ 9 – 12 ]. Recent studies conducted in different parts of the world have shown that there is a substantial reduction in Hepatitis B infections following introduction of vaccination program [ 13 – 15 ]. The most surprising finding of the study was that only 44.4% of the students were vaccinated with Hepatitis B vaccine.…”

Synthesis and cytotoxicity of fused thiophene and pyrazole derivatives derived from 2-N-acetyl-3-cyano-4,5,6,7-tetrahydrobenzo[b]thiophene

“…In the US and other western countries, alcohol-related cirrhosis, and possibly nonalcoholic fatty liver disease associated with obesity, is account for the majority of liver cancer cases. Chronic infections with hepatitis B virus (HBV) and hepatitis C virus (HCV) are associated with less than half of liver cancer cases in the US, although they are the major risk factors for the disease worldwide (Upreti et al, 2014). Although chemotherapy is the mainstay of cancer therapy, the use of available chemotherapeutics is often limited mainly due to undesirable side effects and a limited choice of available anticancer drugs (Goutham Vemana et al 2014).…”