Chronic hepatitis B is the world's leading cause of liver cancer (hepatocellular carcinoma) and cirrhosis. In 2022, an estimated 5 million people in the World Health Organization's Region of the Americas were living with it, and about 20,000 died of hepatitis B–related causes. Most chronic infections begin at birth, from the mother, or in early childhood — infections before age 5 are the likeliest to become chronic — and they can be prevented by vaccination.
The vaccine and the targets
WHO recommends that every infant get a birth dose of hepatitis B vaccine (HepB-BD) within 24 hours of birth, followed by two or three more doses (HepB3) in the first months of life, alongside diphtheria-tetanus-pertussis vaccine.
| PAHO (the Americas, "EMTCT Plus," 2017) | WHO (global) | |
|---|---|---|
| Impact target | chronic infection (HBsAg) ≤0.1% in children aged 4–6 | ≤0.1% in children aged 5 and under |
| Vaccine coverage | timely HepB-BD and HepB3 ≥95% nationally and >85% in every province or area | timely HepB-BD and HepB3 ≥90% for the two most recent years |
| Pregnancy care | ≥80% of pregnant women tested for HBsAg, and hepatitis B immunoglobulin (HBIG) for exposed newborns | — |
The Pan American Health Organization (PAHO) recommended universal infant vaccination in 1999 and a universal birth dose in 2011, and in 2017 added hepatitis B (and Chagas disease) to its strategy for eliminating mother-to-child transmission of HIV and syphilis.
Progress
Every one of the region's 51 countries and territories had universal HepB3 vaccination by 2012, and 34 (67%) gave a universal birth dose by 2021.
Regional coverage with the third hepatitis B dose and the timely birth dose. CDC
| Coverage | |
|---|---|
| HepB3, regional | rose through the 1990s; 88%–91% in 2005–2016; fell to 79% in 2019; 83% in 2022 |
| HepB3, 2012 → 2022 | down 10 points or more in 15 of 41 countries with data for both years, and 13 points or more in the Andean, Central American, and Southern Cone and Brazil subregions. Haiti never passed 68%, Suriname never 81% |
| HepB3 targets met in both 2021 and 2022 | 12 countries at ≥90%; 5 of them at ≥95% |
| Birth dose, regional | up from 23% (2000) to 65% (2022) |
| Birth dose, 2012 → 2022 | down 10 points or more in Argentina, Costa Rica, Mexico and Venezuela |
| Birth-dose targets met in both 2021 and 2022 | 7 countries at ≥90%; 5 at ≥95% |
| Both ≥95% in both years | 3 countries |
Chronic infection in children. Three mathematical models put regional prevalence among children 5 and under below 0.1%. Of 26 countries with all three estimates, all three models put 14 at or below 0.1% — and two of those, Chile and Cuba, also had HepB3 and birth-dose coverage of 95% or more in 2021 and 2022, with antenatal and maternal-child policies in place, meeting both regional and global criteria. National surveys in Haiti, Mexico and the United States back the model estimates, and local surveys show less infection among generations old enough to have been vaccinated than among older ones.
Pregnancy care. Of 35 countries reporting to PAHO, 19 had national elimination goals by 2020. In 21 of 43 countries, at least 90% of pregnant women had four or more prenatal visits; in 27 of 30, at least 91.5% of births were in health facilities. 27 of 32 countries reported universal antenatal hepatitis B testing, and 24 of 32 provided HBIG for babies of mothers with high viral loads — though how many people these reach is often unknown.
What stands in the way
An estimated 34,000 children aged 5 and under in the Americas had chronic hepatitis B in 2022, and few countries consistently reach 90% HepB3 coverage. The slide since 2012 has been blamed on:
- weak, unsustainable financing and less social mobilization for vaccination;
- growing vaccine hesitancy;
- insecurity from civil unrest;
- poor access to health services for some groups;
- the COVID-19 pandemic and its disruptions.
And 17 countries — 13 of them in the Caribbean and Latin Caribbean — have not introduced a universal birth dose.
What's being done
- PAHO is helping countries carry out its 2021 resolution on reinvigorating immunization and the new Regional Immunization Action Plan 2030.
- Because most births are in health facilities, standing orders to vaccinate newborns before discharge, plus education for pregnant women and staff, can improve timely birth doses.
- Antenatal testing, antiviral treatment in pregnancy where needed, and HBIG are being built into the existing HIV and syphilis programs; PAHO's Strategic Fund works to cut the cost of hepatitis B supplies and medicines.
- PAHO has set up a process, with regional and national committees, to validate elimination — which needs representative surveys of children. Newer approaches include adding HBsAg tests to other surveys, or focusing on high-risk areas, as Colombia's two-phase verification did.
Limits
- Schedules, coverage and program indicators were missing for some countries and years.
- Not every country separates timely birth doses from later ones, so timely coverage may be overestimated.
Sources
Based on Alleman MM, Soares Sereno L, Whittembury A, et al., "Progress Toward Elimination of Mother-to-Child Transmission of Hepatitis B Virus — Region of the Americas, 2012–2022," MMWR Morbidity and Mortality Weekly Report volume 73, number 29, Centers for Disease Control and Prevention; a work of the United States government in the public domain.
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