Horizontal Modes of Transmission of Hepatitis B Virus (HBV): A Systematic Review and Meta-Analysis

Background: horizontal transmission of hepatitis b virus (hbv) is a significant transmission route in house-holds, among contact sport athletes and institutionalized individuals. children often are infected by non-sexual close contacts with an increased tendency to become chronic carriers. hence, the awareness about various high-risk behaviours leading to horizontal transmission in the community is essential. a systematic review and meta-analysis was carried out to assess quantitatively the pooled prevalence of horizontally transmitted hbv infection globally.methods: the study was started after ruling out registered or ongoing systematic reviews related to this topic in the prospero database. the study protocol was documented in prospero with a registration number crd42021235165. we searched electronic databases for published articles in english between 1981 and april 2021 reporting horizontal modes of hepatitis b transmission among unvaccinated contacts. meta-analysis was carried out in stata version 13.0 (college station, texas 77,845 usa). the forest plots were constructed using metaprop package in stata.results: forty-one studies were systematically reviewed and 15 studies were qualified for the meta-analysis, including 1619 hepatitis b cases and 4869 contacts. the overall pooled prevalence of horizontally transmitted hbv infection among the contacts was 38% (95% ci 30%-46%). the pooled prevalence among 3,912 house-hold contacts from nine qualified studies was estimated as 44% (95% ci 35%-54%). the pooled prevalence rates among institutionalized individuals and contact sport athletes were 30% (95% ci 23%-37%) and 18% (95% ci 5%-32%), respectively.conclusion: the likelihood of horizontal transmission of hbv is greater among household contacts of chronic carriers of hbv and institutionalized individuals.