Additional research is needed to more clearly define rates of HBV infection among different populations in SSA, including PLHIV, and the full extent of HBV-associated morbidity and mortality among PLHIV in the new ART era. Resources allowing countries without quality data are encouraged to gather epidemiologic data on HBV and HIV/HBV co-infection rates, especially within the context of large HIV-focused and other population surveillance studies. Such research and enhanced surveillance could inform future decision making about resource allocation for HBV screening and treatment not only through an HIV-specific lens, but also in consideration of the potential need for HBV treatment more broadly and in comparison with the other pressing health needs. HBV testing might be reasonably integrated into large cohort studies and demographic surveillance systems that have been established to study HIV in SSA and other global regions, minimizing the cost of de novo or focused hepatitis B studies and surveillance. The outputs could provide much-needed population-based HBV infection estimates, identify locales and subpopulations at highest risk, and provide useful data on the natural history of HBV in Africa. Existing samples or planned specimen collections could be tested for HBsAg, HBeAg, and HBV DNA at a relatively lower cost. Populations from SSA should also be prioritized in future studies to characterize the risk/benefit ratio of ART for HBV-related HCC because previous research has not addressed the issue well. Because momentum builds to do more to address the major global health problem of viral hepatitis, particularly impacting SSA, integration of HBV testing and treatment within existing HIV treatment platforms can benefit PLHIV.
Countries may also be able to identify more synergistic and cost-effective ways to better characterize HBV infection burden in their generalized populations and strengthen HBV testing, care and treatment, as well as prevention by building on the infrastructure and capacities established for HIV programs. Implementation research and demonstration projects related to HBV testing and treatment should be contemplated to begin to provide data on feasibility, acceptability, cost, and logistical requirements of HBV treatment in different contexts and populations in SSA.
Better data on HBV treatment costs and logistics for HBV mono-infection will be critical to inform decision making about whether to prioritize treatment for different populations, not only within but also beyond demonstration projects. The currently recommended first-line antiviral agents for HBV treatment—either oral TDF or entecavir (ETV)—are both highly effective as monotherapy against all HBV genotypes, with very low rates of serious adverse events, less laboratory monitoring requirements than ART, and minimal resistance occurring during long-term therapy of 5 years or more among treatment-naive patients (1.2% resistant with ETV97 and 0% with TDF98). Furthermore, the recommended doses of TDF 300 mg or ETV 0.5 mg daily formulations for HBV treatment are available as low-cost generic tablets for HIV treatment in SSA. However, simplified protocols for initiating and following patients with HBV mono-infection in RLS are still under development.
This summary of evidence may be useful to national HIV/AIDS programs considering implementing HBV screening programs. Continued research is needed to quantify the effectiveness of screening and identify best practices for implementation of a screening program.
We thank Gail Bang and Emily Weyant of the Division of Global HIV/AIDS, Centers for Disease Control and Prevention, Atlanta, GA, for their work in generating the initial list of abstracts used for this literature review.
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