Progress Toward Hepatitis B Control — World Health Organization European Region, 2016–2019

In 2019, an estimated 14 million persons in the World Health Organization (WHO) European Region* (EUR) were chronically infected with hepatitis B virus (HBV), and approximately 43,000 of these persons died from complications of chronic HBV infection (1). In 2016, the WHO Regional Office for Europe set hepatitis B control program targets for 2020, including 1) ≥90% coverage with 3 doses of hepatitis B vaccine (HepB3), 2) ≥90% coverage with interventions to prevent mother-to-child transmission (MTCT) of HBV,† and 3) ≤0.5% prevalence of HBV surface antigen (HBsAg)§ in age groups eligible for vaccination with hepatitis B vaccine (HepB) (2-4). This report describes the progress made toward hepatitis B control in EUR during 2016-2019. By December 2019, 50 (94%) of 53 countries in EUR provided routine vaccination with HepB to all infants or children aged 1-12 years (universal HepB), including 23 (43%) countries that offered hepatitis B birth dose (HepB-BD) to all newborns. In addition, 35 (73%) of the 48 countries with universal infant HepB vaccination reached ≥90% HepB3 coverage annually during 2017-2019, and 19 (83%) of the 23 countries with universal birth dose administration achieved ≥90% timely HepB-BD coverage¶ annually during that period. Antenatal hepatitis B screening coverage was ≥90% in 17 (57%) of 30 countries that selectively provided HepB-BD to infants born to mothers with positive HBsAg test results. In January 2020, Italy and the Netherlands became the first counties in EUR to be validated to have achieved the regional hepatitis B control targets. Countries can accelerate progress toward hepatitis B control by improving coverage with HepB and interventions to prevent MTCT and documenting achievement of the HBsAg seroprevalence target through representative serosurveys or, in low-endemicity countries, antenatal screening.

In 2019, an estimated 14 million persons in the World Health Organization (WHO) European Region* (EUR) were chronically infected with hepatitis B virus (HBV), and approximately 43,000 of these persons died from complications of chronic HBV infection (1). In 2016, the WHO Regional Office for Europe set hepatitis B control program targets for 2020, including 1) ≥90% coverage with 3 doses of hepatitis B vaccine (HepB3), 2) ≥90% coverage with interventions to prevent mother-to-child transmission (MTCT) of HBV, † and 3) ≤0.5% prevalence of HBV surface antigen (HBsAg) § in age groups eligible for vaccination with hepatitis B vaccine (HepB) (2)(3)(4). This report describes the progress made toward hepatitis B control in EUR during 2016-2019. By December 2019, 50 (94%) of 53 countries in EUR provided routine vaccination with HepB to all infants or children aged 1-12 years (universal HepB), including 23 (43%) countries that offered hepatitis B birth dose (HepB-BD) to all * EUR is one of six WHO regions and consists of the following 53 member states (total population, approximately 932 million): Albania, Andorra, Armenia, Austria, Azerbaijan, Belarus, Belgium, Bosnia and Herzegovina, Bulgaria, Croatia, Cyprus, Czechia, Denmark, Estonia, Finland, France, Georgia, Germany, Greece, Hungary, Iceland, Ireland, Israel, Italy, Kazakhstan, Kyrgyzstan, Latvia, Lithuania, Luxembourg, Malta, Moldova, Monaco, Montenegro, Netherlands, North Macedonia, Norway, Poland, Portugal, Romania, Russia, San Marino, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Tajikistan, Turkey, Turkmenistan, Ukraine, United Kingdom, and Uzbekistan. † In EUR, interventions to prevent MTCT of HBV include either 1) administering a timely birth dose of HepB vaccine to all newborns (universal birth dose policy) or 2) conducting routine antenatal screening of pregnant women for hepatitis B and vaccinating infants born to HBV-infected mothers with HepB birth dose within 24 hours of birth (selective birth dose policy), either of which is followed by ≥2 additional vaccine doses according to the national immunization schedule. In addition, some countries provide antiviral treatment to pregnant women with positive HBsAg test results and administer hepatitis B immune globulin at birth to infants of infected mothers. § Before introduction of vaccination, the HBV endemicity in EUR, defined by HBsAg antigen seroprevalence, ranged widely from low (<2.0%) in 25 countries, to intermediate (2.0%-7.9%) in 25 countries, to high (≥8.0%) in three countries.
newborns. In addition, 35 (73%) of the 48 countries with universal infant HepB vaccination reached ≥90% HepB3 coverage annually during 2017-2019, and 19 (83%) of the 23 countries with universal birth dose administration achieved ≥90% timely HepB-BD coverage ¶ annually during that period. Antenatal hepatitis B screening coverage was ≥90% in 17 (57%) of 30 countries that selectively provided HepB-BD to infants born to mothers with positive HBsAg test results. In January 2020, Italy and the Netherlands became the first counties in EUR to be validated to have achieved the regional hepatitis B control targets. Countries can accelerate progress toward hepatitis B control by improving coverage with HepB and interventions to ¶ A timely HepB birth dose is defined as a dose administered within 24 hours of birth. prevent MTCT and documenting achievement of the HBsAg seroprevalence target through representative serosurveys or, in low-endemicity countries, antenatal screening.

Immunization Activities
As a major intervention to prevent perinatal and childhood hepatitis B infections, WHO recommends that all infants receive ≥3 doses of HepB, including a timely birth dose (5). Most countries in EUR introduced HepB vaccination >15 years ago (Table 1). Countries report information on immunization schedules and coverage annually to WHO and UNICEF using the WHO/UNICEF Joint Reporting Form. WHO and UNICEF review administrative coverage data and surveys to generate country-specific coverage estimates.** In 2019, 48 (91%) of the 53 countries in EUR provided universal routine infant HepB vaccination, two † † (4%) (Hungary and Slovenia) provided universal routine HepB vaccination to children aged 5-12 years, and three countries (6%) (Denmark, Finland, and Iceland) implemented selective HepB vaccination, only immunizing those born to mothers with positive HBsAg test results. § § Twenty-three (43%) countries provided HepB-BD to all newborns, and 30 (57%) provided HepB-BD selectively to children born to mothers ** https://immunizationdata.who.int/listing.html?topic = coverage&location = eur † † In Hungary, HepB is given at age 12 years, and in Slovenia, it is given at age 5-6 years.

Antenatal Screening and Postexposure Prophylaxis
The 30 countries that implement a selective HepB-BD policy aim to prevent MTCT of HBV infection through antenatal HBV screening combined with postexposure prophylaxis of infants born to mothers with positive HBsAg test results. Information on implementation of these interventions is not routinely reported to WHO. Based on the responses to a survey conducted by the WHO Regional Office for Europe in ¶ ¶ Norway and the United Kingdom in 2017, and Switzerland in 2018. *** Austria, Bosnia and Herzegovina, Germany, Montenegro, San Marino, and Ukraine. † † † Bosnia and Herzegovina and Russia do not report HepB-BD coverage.   2018 § § § and published reports, 29 (97%) of those 30 countries ¶ ¶ ¶ conducted nationwide antenatal screening for HBsAg (Table 1). Antenatal screening coverage data were available for 20 (69%) of these countries, and 17 (85%) reported ≥90% coverage.**** Among infants born to HBV-infected mothers in these countries, § § § The survey was sent to the 50 member states of EUR that implement universal HepB vaccination and included questions on HepB vaccination policy, practices, and measures to prevent perinatal transmission of HBV. Survey questions were designed to account for differences in HepB-BD policy between the member states (universal versus selective). Forty-three (86%) countries, including 22 of 23 countries with universal HepB-BD policy and 21 of 30 countries with selective HepB-BD policy, responded to the survey. ¶ ¶ ¶ Montenegro reported not having nationwide antenatal screening in place. **** Six countries (Czechia, Estonia, France, Greece, Ireland, and Luxembourg) also had ≥90% coverage with routine HepB3 among infants each year during 2017-2019 (i.e., met the validation criteria for immunization).

HBsAg Seroprevalence
Because most chronic HBV infections are asymptomatic, particularly among young children, the impact of hepatitis B vaccination is assessed based on the HBsAg seroprevalence among children (6). However, in EUR, because of early regional introduction of HepB, the age group for serosurveys for validation purposes is defined as cohorts eligible for HepB vaccination. For EUR countries with low endemicity before vaccine introduction (prevaccine), where conducting largescale hepatitis B serosurveys might not be justified, HBsAg seroprevalence of ≤0.5% among pregnant women is considered acceptable evidence that the seroprevalence target was achieved.
By December 2019, representative nationwide or regional serosurveys have demonstrated ≤0.5% HBsAg seroprevalence in at least one vaccinated or partially vaccinated age group in five countries and in a prevaccine cohort in one country (the Netherlands) ( Table 2). Serosurveys initiated recently for validation purposes in several countries, in some cases with support from WHO and other international partners, have been put on hold because of the COVID-19 pandemic. HBsAg seroprevalence of ≤0.5% among pregnant women has been reported from nine (36%) of 25 countries with low endemicity, sometimes with higher prevalence among foreign-born women than among women who were not foreign-born (e.g., Denmark, Italy, and the Netherlands) ( Table 2).

Validation
The Hepatitis B Regional Working Group of the European Technical Advisory Group of Experts was established in 2017 and developed the framework and criteria for validation of achievement of the regional hepatitis B control targets for countries in EUR ( Table 3). The validation process was initiated in 2019. In 2019, the regional validation criteria for immunization coverage were met for HepB3 by 35 (73%) of 48 countries providing universal infant HepB vaccination and for timely HepB-BD by 19 (83%) of 23 countries implementing universal newborn vaccination, including 17 (32%) countries that met both criteria (Table 1). In January 2020, Italy and the Netherlands were validated to have achieved the regional hepatitis B control targets. The United Kingdom received conditional validation based on fully meeting the MTCT prevention and seroprevalence criteria (in antenatal screening), and by partially meeting immunization coverage criteria pending availability of 3 full years of data. ¶ ¶ ¶ ¶ Croatia received conditional validation pending clarification of methods for assessing coverage with MTCT prevention interventions. ¶ ¶ ¶ ¶ At the time of review of the validation documents by the WHO European Regional Hepatitis B Working Group, 3 years had not yet passed since introduction of universal HepB vaccination in the United Kingdom in mid-2017.

Discussion
During 2016-2019, EUR made substantial progress toward achieving hepatitis B control, resulting in validation of the first two countries (Italy and the Netherlands) and conditional validation of two other countries (Croatia and the United Kingdom). This progress is supported by a recent modeling study, which demonstrated 0.1% HBsAg seroprevalence among children aged 5 years in EUR (3). Among the 49 countries that have not yet initiated the validation process, 17 (74%) of 23 with a universal HepB-BD policy have met the HepB3 coverage and HepB-BD coverage criteria, and six (23%) of 26 countries with a selective birth dose policy met HepB3 coverage and antenatal screening coverage targets. Eight (16%) of these 49 countries met the ≤0.5% HBsAg seroprevalence target.
To accelerate validating achievement of the regional hepatitis B control target in EUR, some countries could consider submitting available documentation for validation, whereas others still need to generate the evidence required for validation. Although conducting nationally representative hepatitis B serosurveys might be challenging, and because the COVID-19 pandemic has further challenged their implementation, hepatitis B testing can be incorporated into other nationally representative serosurveys, including COVID-19 serosurveys, where feasible.
The historic differences in HBsAg prevalence and the diversity of HepB immunization strategies across EUR necessitated a differential approach to validation of hepatitis B control depending on national prevaccine endemicity and HepB vaccination policies. Although HepB3 immunization coverage is high in most countries, it remains consistently <90% in six countries, reflecting challenges in their immunization services. Countries can address these challenges by 1) providing sufficient support to national immunization programs to strengthen immunization systems, 2) monitoring public perception toward vaccinations and developing tailored strategies to create demand for vaccination among all population groups, and 3) strengthening immunization information systems to improve quality and availability of coverage data (6)(7)(8). The two countries in EUR with universal birth dose policy that currently do not report HepB-BD coverage (Bosnia and Herzegovina and Russia) will need to establish systems for monitoring and reporting birth dose coverage.
In countries that provide selective HepB-BD vaccination, establishing systems for continual monitoring of coverage with antenatal screening and HBsAg-positivity among pregnant women and of coverage with HepB-BD and HepB3 among exposed infants is needed to provide reliable data on seroprevalence and interventions to prevent MTCT of HBV for validation purposes. Available seroprevalence data showed a much higher prevalence of hepatitis B among foreign-born  (9). The findings in this report are subject to at least three limitations. First, missing HepB-BD coverage data for Bosnia and Herzegovina and Russia prevent determining whether these countries have met the HepB-BD coverage target. Second, timely HepB-BD coverage estimates might not be accurate for countries that do not monitor timeliness of HepB-BD administration. Finally, some HBsAg seroprevalence estimates were obtained >15 years ago and might not reflect the current prevalence in cohorts eligible for vaccination.
Despite progress made during 2016-2019, achieving the 2020 hepatitis B control goal in EUR will require programmatic improvements in underperforming countries. To accelerate the validation process, most countries will need to generate additional evidence of having achieved the regional targets. Some low-and middle-income countries will require continued external support to conduct serosurveys. Further, the COVID-19 pandemic has caused disruptions in immunization services and led to delays in implementation of serosurveys.

Summary
What is already known about this topic?
In 2019, 14 million persons in the World Health Organization European Region (EUR) were chronically infected with hepatitis B virus.
What is added by this report?
During 2016-2019, EUR made substantial progress towards hepatitis B control. Of 53 countries in EUR, 35, 19, and 17 countries met coverage targets for 3 doses of hepatitis B vaccine, the birth dose, and for hepatitis B screening of pregnant women, respectively. Two countries (Italy and the Netherlands) have achieved hepatitis B control.
What are the implications for public health practice? Improving hepatitis B vaccination coverage, screening of pregnant women, and conducting hepatitis B seroprevalence assessments can help EUR to accelerate progress and document achievement of hepatitis B control targets. Implementing the regional guidance on interventions to mitigate the impact of COVID-19 on immunization programs can help countries maintain or improve HepB vaccination coverage and accelerate progress toward the regional goal (10).