Prevalence of hepatitis B virus infection among health care workers in a tertiary hospital in Tanzania

Abstract

BackgroundSub-Saharan Africa has a high prevalence of hepatitis B virus (HBV) infections. Health care workers (HCWs) are at high risk of contracting HBV infection through their occupation. Vaccination of HCWs against HBV is standard practice in many countries, but is often not implemented in resource-poor settings. We aimed with this cross-sectional study to determine HBV prevalence, HCW vaccination status, and the risk factors for HCWs contracting HBV infection in Tanzania.MethodsWe enrolled 600 HCWs from a tertiary Tanzanian hospital. Their demographics, medical histories, HBV vaccination details and risk factors for contracting blood-borne infections were collected using a standardized questionnaire. Serum samples were tested for HBV and hepatitis C virus (HCV) markers by ELISA techniques, PCR and an anti-HBs rapid test. HCWs were divided in two subgroups: those at risk of contracting HBV (rHCW 79.2 %) via exposure to potentially infectious materials, and those considered not at risk of contracting HBV (nrHCW, 20.8 %).ResultsThe overall prevalence of chronic HBV infection (HBsAg+, anti-HBc+, anti-HBs-) was 7.0 % (42/598). Chronic HBV infection was found in 7.4 % of rHCW versus 5.6 % of nrHCW (p-value = 0.484). HCWs susceptible to HBV (HBsAg-, anti-HBc-, anti-HBs-) comprised 31.3 %. HBV immunity achieved either by healed HBV infection (HBsAg-, anti-HBc+, anti-HBs+) or by vaccination (HBsAg-, anti-HBc-, anti-HBs+) comprised 36.5 % and 20.2 %, respectively. 4.8 % of participants had indeterminate results (HBsAg-, anti-HBc+, anti-HBc-IgM-, anti-HBs-). Only 77.1 % of HCWs who received a full vaccination course had an anti-HBs titer >10 ml/U. An anti-HBs point-of-care test was 80.7 % sensitive and 96.9 % specific. There was a significantly higher risk for contracting HBV (anti-HBc+) among those HCW at occupational risk (rHCW) of older age (odds ratios (OR) in rHCW 3.297, p < 0.0001 vs. nrHCW 1.385, p = 0.606) and among those HCW being employed more than 11 years (OR 2.51, p < 0.0001***). HCV prevalence was low (HCV antibodies 1.2 % and HCV-RNA 0.3 %).ConclusionsChronic HBV infection is common among Tanzanian HCWs. One third of HCWs were susceptible to HBV infection, highlighting the need for vaccination. Due to high prevalence of naturally acquired immunity against HBV pre-testing might be a useful tool to identify susceptible individuals.

Prevalence and vaccination coverage of Hepatitis B among healthcare workers in Cameroon: A national seroprevalence survey

“…These data corroborate others from tertiary hospitals in Tanzania and Uganda, which also found remarkably high prevalence of HBsAg positivity in HCWs, at 7.0% and 8.1% respectively. 25 Our findings are also comparable to estimates in other high-risk groups in Cameroon. Frambo et al reported a prevalence of 9.7% among pregnant women, and Noubiap et al reported a prevalence of 10.1% in blood donors.…”

“…More than 2 billion people have been infected with Hepatitis B virus (HBV) globally, and 240 million are chronic carriers of the disease. 1,2 Africa is considered to be endemic for HBV; and the disease is hyperendemic in Cameroon where prevalence has been estimated at 11.9%. 3,4 Healthcare workers (HCWs) are one of the most vulnerable groups to HBV infection from occupational exposures, with up to four times greater risk of contracting the infection than the general population.…”

Hepatic Encephalopathy; Prevalence, Precipitating Factors and Challenges of Management in a Resource-Limited Setting

“…This could partly be explained due to high prevalence of viral hepatitis B infection in the younger adults which is among the commonest causes of acute and chronic liver failure to both the general and health care worker populations in Tanzania [12,13]. The male predominant population in this study is likely due to the risk of chronic alcohol use as a cause of liver disease which was consistent with other studies [11].…”

Incidence of Elevated Aminotransferases Levels among Patients Presenting with Hepatitis Syndrome in the Northwest Region of Cameroon

“…They are considered as one of World Health Organization (WHO) public health priority after the HIV infection, malaria and tuberculosis [2,3]. Worldwide, it is estimated that more than 2 billion people and 170 million people are infected with hepatitis B virus (HBV) and hepatitis C virus (HCV) respectively with 3 -4 million new infections occurring each year [4,5]. The prevalence of HB and HC is highest in subSaharan Africa and East Asia, with an estimated 5-10% adults with chronic infection [2].…”

“…The prevalence of HB and HC is highest in subSaharan Africa and East Asia, with an estimated 5-10% adults with chronic infection [2]. Of these, 240 million people are chronic carriers of HBV and are at risk of death from acute fulminant liver disease, hepatocellular carcinoma (HCC) or liver cirrhosis [5,6]. In Cameroon the prevalence of HBV ranges from 6.3-11.5% [7] while the range of HCV is 6.9% -56.0% [8][9][10].…”