Hepatitis B in Africa: Progress Toward Stopping Mother-to-Child Transmission, 2016–2021

Chronic hepatitis B virus (HBV) infection is one of the leading causes of cirrhosis and liver cancer. In 2019, approximately 1.5 million people newly acquired chronic HBV infection worldwide — 990,000 (66%) of them in the World Health Organization (WHO) African Region. Most chronic infections are passed from mother to child at birth or in early childhood.

WHO therefore recommends a birth dose of hepatitis B vaccine within 24 hours of birth, followed by two or three more doses in the first year.

The goals

Vaccination

• All 47 countries had added the three-dose infant vaccine by 2014.
• Only 14 (30%) gave a birth dose by December 2021 — 8 of them in West Africa. Just four — Benin, Côte d’Ivoire, Equatorial Guinea and Senegal — introduced it during 2016–2021.
• Regional HepB3 coverage slipped from 75% in 2019 to 71% in 2021. The number of countries at ≥90% peaked at 20 in 2018 and fell to 16 by 2021 as COVID-19 disrupted immunization.
• Regional birth-dose coverage rose from 10% to 17%. Algeria and Cabo Verde reached ≥90%; Namibia and Senegal passed 50%. Still, almost 33 million newborns in the region did not get a timely birth dose in 2021.

Measuring infection

Because most chronic infections in young children cause no symptoms, success is measured by blood tests for hepatitis B surface antigen (HBsAg) among children born after vaccination began. During 2016–2021 only eight countries ran such surveys.

• Among surveyed children in Ethiopia, Mauritania, Rwanda, Sierra Leone, Uganda and Zambia, infection was ≤2%.
• Among children 5 and under, it ranged from 0.7% in Mauritania to 4.5% in Nigeria.
• No country reached the ≤0.1% elimination level.
• Models estimate 2.5% of young children in the region are infected — about 4.3 million, roughly 69% of all infected children worldwide.
• Among women of reproductive age or pregnant women in 11 countries, infection ranged from 1.2% (Rwanda) to 9.8% (Sierra Leone) — a measure of the risk to their babies.

Four countries met the definition of hepatitis B control: ≥90% HepB3 coverage for at least two years and under 2% infection in children.

Preventing transmission at birth

• 21 countries had plans to eliminate mother-to-child transmission of HIV, syphilis and hepatitis B, but only six had put the hepatitis B steps into practice: testing pregnant women, giving antiviral medicine to eligible mothers, and vaccinating newborns at birth.
• Only 17 countries had national policies for HBsAg testing and treatment in pregnancy.
• In 29 countries, at least 90% of pregnant women had at least one antenatal visit; in 23, at least 80% gave birth in a health facility — important, because births attended by skilled workers in facilities are linked to timely birth doses.
• WHO’s bronze, silver and gold tiers recognize progress: on 2021 vaccination data, Botswana might qualify for bronze, Namibia, São Tomé and Príncipe and Senegal for silver, and Algeria and Cabo Verde for gold.

What would speed progress

• Recover from pandemic disruptions with catch-up vaccination.
• Introduce and scale up the birth dose. Of the 33 countries without it in 2021, Burkina Faso and Uganda added it in 2022 and 13 more planned to by 2025 — but reaching the regional target of 35 countries by 2025 would take six to seven new countries a year. Keeping HepB3 coverage steady and raising birth-dose coverage to ≥90% everywhere could prevent an estimated 554,318 hepatitis B deaths among children born in 2020–2030.
• Encourage facility births, train health workers, and build the birth dose into newborn care.
• Test pregnant women and treat those who need it.
• Run representative serosurveys, and set up a regional body to verify elimination.

Limits: five countries did not consistently report birth-dose coverage, so regional coverage may be underestimated, and many countries lack the representative surveys needed to judge control and elimination.

Sources

Based on "Progress Toward Hepatitis B Control and Elimination of Mother-to-Child Transmission of Hepatitis B Virus — World Health Organization African Region, 2016–2021," MMWR Vol. 72, No. 29, CDC; a work of the United States government in the public domain.