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Prevention and control of perinatal hepatitis B virus (HBV) transmission in the WHO European Region

Meeting conclusions

A review of the current epidemiology of viral hepatitis and perinatal HBV transmission in Central Asian countries, South Caucasus and Turkey revealed that:

  • HBV is the leading cause of CLD in high-endemicity countries in comparison to HCV in low-endemicity countries;
  • Countries have intermediate or high HBV endemicity, with variations in prevalence rates across countries, including socioeconomic and rural/urban differences;
  • Very high rates (up to 20%) of HDV were reported in some countries;
  • Transmission is predominantly perinatal although the route remains unknown in many cases; early childhood, parenteral and sexual routes are also significant;
  • Higher HBeAg positivity results in increased transmission rate;
  • Results of questionnaire from 8 countries showed that 2006 surveillance data were comprehensive and of improving quality,thus contributing to a better definition and quantification of disease burden, necessary for the implementation of national vaccination strategies.

An overview was provided of current recommendations and country practice on universal HBV vaccination programmes, birth dose
administration, maternal screening and HBIg administration:

  • All countries have introduced universal HBV vaccination, with a major effort to administer the birth dose within 24 hours, and with flexibility on the timing of the third dose (as a function of existing vaccination programmes); all using monovalent HBV vaccine for the birth dose; high coverage rates were reported in all countries, with improvements in cold chain functioning. All countries have centralized vaccine procurement, mostly through international agencies;
  • The universally agreed recommendation (VHPB, WHO, CDC) for the birth dose is "as near as possible to birth", and preferably within 24 hours. However, outside healthcare facilities, more flexible schedules (even up to 7 days after birth) are adopted (even though not recommended), to reflect realities in the field;
  • Considerable variations were reported in % of births within healthcare facilities (often >95%) or at home (30% or more in some countries or regions);
  • There is no specific contraindication to the use of HBV vaccine in neonates other than WHO-specified allergic reaction to any vaccine component or anaphylaxis to previous dose. However, results from questionnaire in 8 countries revealed numerous false arguments;
  • For preterm babies (<2kg): low birth weight is not a contraindication to HBV vaccination. HBV vaccine is safe but with possibly reduced immunogenicity, therefore preterm babies should receive birth dose within 24h , followed by three (and not two) subsequent doses;
  • Different policies and practice were reported across countries on maternal screening; maternal screening is costly and not necessarily relevant in view of a birth dose programme;
  • Current data indicate that HBIg administration only adds marginal advantage to protective efficacy; existing national policies of giving HBV vaccine alone are therefore justifiable.

Scientific evidence on prevention and control of HBV transmission through vaccination was summarized and country experiences were shared:

  • Data from several countries provide conclusive evidence of the protective efficacy of HBV newborn vaccination;
  • Many studies testified the significant reduction in disease and infection rates that followed HBV vaccination programmes;
  • Routine booster doses following HBV universal vaccination programmes are not advocated in the national hepatitis B programmes;
  • A flexible mathematical model can be tailored to individual country situations and can be used to assist the policy-making process and implementation of HBV vaccination programmes.

On the basis of presentations, discussions and feedback from workshops, as well as results from questionnaire in 8 countries, a list of keys and challenges to successful HBV vaccination programmes were identified, regarding:

  • Importance of a favourable political and public health framework allowing for adequate disease surveillance, reliable case reporting systems, improved healthcare capacities and sustainable vaccination programmes;
  • Strategies to overcome field difficulties, such as OCC (combined with new tools, such as Uniject™ and VVMs) and better use of existing structures and staff;
  • Development of training and communication programmes for the public and medical profession in order to raise general disease awareness and redress widespread misconceptions, e.g. false contraindications to vaccination.

The role of the following partner agencies and organizations wasreaffirmed and a pledge was made to them to continue to prioritize
HBV vaccination:

  • WHO, UNICEF, World Bank, Asian Development Bank, GAVI, Government of Japan, VHPB;
  • Governments and national ministries, especially of health and finance, agencies (e.g. CDC, US Agency for International
    Development) and universities;
  • Foundations and nonprofit organizations, e.g. Bill and Melinda Gates, PATH, Vishnevskaya-Rostropovich Foundation (VRF);
    l New partnership: 5 United Nations Agencies (Mother and child health context).

Lessons learnt and recommendations

  • Bring vaccine delivery to the neonate: participating countries have achieved success in vaccinating neonates, but challenges remain in terms of coverage and timeliness;
  • HBV vaccination provides a safety net against perinatal HBV transmission, and also prevents early childhood, parenteral and later sexual transmission; HBV vaccination also protects against HDV;
  • HBV vaccine can be administered successfully and effectively with other vaccines (e.g. BCG and OPV);
  • Combined vaccines have good immunogenicity and can replace monovalent vaccines, except for the birth dose in areas of high HBV endemicity;
  • Ensure sustainable vaccine procurement by involving finance and health ministries;
  • Clear specifications are needed in vaccine tenders: e.g. provide vaccines with VVMs, restate open vial policy, provide instructions in appropriate languages;
  • Flexible strategies are needed to modify cold chains (OCC does not mean putting the vaccine in the cold when there is a threat of freezing);
  • New tools (e.g. Uniject™, autodisable syringes, VVMs, OCC approaches) are accepted and training is essential in order to improve vaccine delivery;
  • Data on HBIg confirm that countries’ existing policies of giving HBV vaccine alone are defensible;
  • Guidelines may need revision and/or restatement on cold-chain strategy, administration of birth dose within 24 hours, HBIg administration and open-vial policy;
  • Maternal screening is acceptable if already in place but it is not a high priority compared with universal HBV vaccination of neonates, which is a "worthwhile investment". In countries of high HBV prevalence, maternal screening may not be feasible or the most reliable or convenient option;
  • A mathematical model exists showing that the impact of vaccination is highest in countries with highest rates of perinatal HBV transmission; this model is available and accessible for application of national data;
  • Surveillance systems need to be supported by laboratory systems and there is a general need for capacity building of health systems;
  • Disposal of medical waste is a very general problem without ready solutions;
  • Successes need to be communicated to health professionals (including medical schools) in appropriate language and format: digests of information, fact sheets, etc;
  • There is a need for improved communication at all levels: general public, politicians, and media in appropriate languages;
  • This meeting focused on Central Asian countries, South Caucasus and Turkey, yet conclusions are applicable to many more countries;
  • International fora and workshops are most valuable for exchanging information and relaying important messages and concerns to intergovernmental agencies.

Further information is available in the corresponding Viral Hepatitis Issue or  meeting web page.

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