Hepatitis B in Africa – Why preventing mother-to-child transmission and diagnosing Hepatitis B is so important
The African Viral Hepatitis Advisory Group (AVHAG), is a group of passionate community representatives/patient advocates, clinicians, policy makers and key opinion leaders committed to addressing the challenges of viral hepatitis elimination across Africa. Working within a coordinated approach our goal is to increase awareness, advocacy, research and to drive resource mobilization efforts for the continent.
The AVHAG raises awareness of the underserved need within viral hepatitis with a view to drive political commitment and action by all governments, high net worth individuals and policy making bodies; instigating and harmonizing action on viral hepatitis elimination across Africa. A key driver is finding local solutions to the challenge of Viral Hepatitis elimination across the continent. To mark World Hepatitis Day 2023 the group has issued the following statement:
Hepatitis B in Africa – Why preventing mother-to-child transmission and diagnosing Hepatitis B is so important
There are 82 million people living with hepatitis B virus (PLWHB) in the WHO Africa region, where it is the main cause of liver disease, accounting for 990 000 new infections, and 80 000 HBV-associated deaths annually.1 The majority of infections in Africa are due to mother-to-child transmission (MTCT) and early childhood acquisition under the age of 5 years. Chronicity risk of HBV infection is determined by the age of HBV acquisition: risk of chronic infection is 90% when HBV infection occurs perinatally; 30-50% risk with early childhood acquisition and <10% with adult acquisition. The risk of MTCT depends on the level of HBV replication with the transmission risk increasing with HBV DNA levels >200 000 IU/ml.
Prevention of mother-to-child transmission (PMTCT) of hepatitis B virus infection is the cornerstone of strategies for elimination of hepatitis B: Screening of pregnant women for HBsAg, tenofovir prophylaxis in the second trimester for highly viraemic pregnant women, Hepatitis B birth dose vaccination within 24 hours of delivery and full universal HBV vaccination.2 Specific international public health targets for Hepatitis B include 95% reduction in new infections in children, and lowering the prevalence in 0-5 year olds from 0.9% in 2020 to 0.1% by 2030. In the WHO Africa region, the prevalence in under 5-year olds was 2.53% in 2019, reflecting a failure of maternal and early childhood programmes to prevent Hepatitis B with only 14 countries having introduced the hepatitis B birth dose vaccination.1,3 Of concern, approximately 4.3 million children under the age of 5 years in Africa are HBsAg positive accounting for 68% of all children living with chronic HBV. These children are at a higher risk of developing cirrhosis and hepatocellular carcinoma in early adulthood.4,5 Identifying HBsAg positive pregnant women offers the opportunity to screen partners, siblings and children thereby enabling cycles of infection to be broken by vaccinating those who are non-immune and linking those who are HBV-infected to appropriate care.
Despite effective and affordable antiviral therapy – Tenofovir costs <50 USD per annum – which can prevent the development of cirrhosis and reduce the risk of hepatocellular carcinoma (HCC)6, fewer than 2% of PLWHB are diagnosed and only 0.1% are treated.1 As a result, PLWHB are frequently diagnosed with HBV only when they have already developed decompensated cirrhosis and late-stage HCC. It is estimated that 2.5 million people have HBV-associated cirrhosis in the WHO Africa region. There were an estimated 38 629 new HCC cases in 2020 with most individuals presenting with inoperable, multifocal disease7, reflecting limited access to affordable point-of-care diagnostic HBsAg tests and HBV DNA quantification, screening and surveillance programmes for cirrhosis and HCC, and early linkage to appropriate care.
We call on governments, national departments of health, international agencies, and industry to ensure implementation of simplified Hepatitis B treatment guidelines appropriately adapted to resource-limited settings, where affordable point-of-care diagnostics and antiviral therapy as well as early assessment of the severity of liver disease and accessible pathways to care are a public health priority. Innovative social media campaigns and educational programmes will be important to raise awareness amongst both the public and healthcare workers about a silent liver disease that is vaccine preventable and must be identified and treated before the complications of cirrhosis and HCC arise.
Patient advocacy groups play a critical role to ensure the rights of PLWHB to access affordable diagnostics and long-term antiviral therapy, and clinical trials for future functional cures.
References
- World Health Organization. Global progress report on HIV, viral hepatitis and sexually transmitted infections, 2021.
https://www.who.int/publications/i/item/9789240027077. Accessed 17 June 2021.
- Organization WH. Prevention of mother-to-child transmission of hepatitis B virus: Guidelines on antiviral prophylaxis in pregnancy. https://wwwwhoint/publications/i/item/978-92-4-000270-8 2020.
- UNICEF-WHO. Hepatitis B Vaccine Coverage. 2022.
- Shimakawa Y, Yan HJ, Tsuchiya N, Bottomley C, Hall AJ. Association of early age at establishment of chronic hepatitis B infection with persistent viral replication, liver cirrhosis and hepatocellular carcinoma: a systematic review. PLoS One 2013; 8(7): e69430.
- Shimakawa Y, Lemoine M, Bottomley C, et al. Birth order and risk of hepatocellular carcinoma in chronic carriers of hepatitis B virus: a case-control study in The Gambia. Liver international : official journal of the International Association for the Study of the Liver 2015; 35(10): 2318-26.
- Choi WM, Yip TC, Wong GL, et al. Hepatocellular carcinoma risk in patients with chronic hepatitis B receiving tenofovir- vs. entecavir-based regimens: Individual patient data meta-analysis. J Hepatol 2023; 78(3): 534-42.
- Yang JD, Mohamed EA, Aziz AO, et al. Characteristics, management, and outcomes of patients with hepatocellular carcinoma in Africa: a multicountry observational study from the Africa Liver Cancer Consortium. The lancet Gastroenterology & hepatology 2017; 2(2): 103-11.
For more information contact: africanviralhepatitisadvisoryg@gmail.com
https://africanhepatitisgroup.com/