Dried blood spot scheme for infants born to hepatitis B positive mothers Dr Vanessa MacGregor Iolanda Shaker Yvonne Rodney 16 June 2014
Outline • Hepatitis B – Vanessa MacGregor – Disease – Implications of antenatal infection – Post-exposure prophylaxis – National and local data • Local pathway – Iolanda Shaker – Community pathway – Roles and Responsibilities – Data collection • Dried Blood Spot Scheme – Yvonne Rodney – Service – Kits – Training video
Hepatitis B Infection of the liver caused by Hepatitis B virus The incubation period ranges from 40 to 160 days Extremely infectious (x 100 more infectious than HIV) World-wide, about 1 million people die from acute and chronic HB infection per year, making it one of the major causes of morbidity and mortality in humans.
Modes of transmission The virus is transmitted by exposure to infected blood or body fluids Perinatal (vertical) transmission : Mother to child Horizontal transmission: non-sexual contact with an infected person Parenteral transmission: exposure to blood/other infective fluids Sexual transmission: contact with an infected person
Symptoms of Hepatitis B Infection Acute infection: • Many new infections are subclinical or have flu like illness • Anorexia, nausea, ache in the right upper abdomen, mild fever, malaise, disinclination to smoke or drink • Jaundice occurs in 10% of younger children and 30-50% of adults Chronic infection complications include: • Hepatic cirrhosis • Necrosis • Chronic active hepatitis • Hepatocellular carcinoma
Prevalence of chronic hepatitis B virus infection among adults 6 Presentation title - edit in Header and Footer
Hepatitis B antenatal screening and newborn immunisation programme • Since 2001 – All pregnant women offered antenatal screening – All babies born to HBsAg positive mothers receive a complete course of vaccine (0,1, 2 & 12 months)
Aim of HBV Programme: Reduce mother to child transmission • Risk of mother to child transmission high (without intervention) • For infants of women who are HBeAg +ve: 73-88% become infected • For infants of women who are HBeAg – ve: 7-14% become infected • 90% infected babies become chronically infected (risk of liver cirrhosis and liver cancer) • Almost all infections will be asymptomatic in infancy: unrecognised unless HBsAg testing performed
Antenatal Screening Programme Objectives • All pregnant hepatitis b positive women are identified • All pregnant hepatitis B positive women are referred for assessment and management by an appropriate specialist • Appropriate discussion is undertaken with positive cases to ensure that – Notification to PHE is undertaken – Testing and vaccination of family and other close contacts is undertaken • The infant vaccination schedule is offered for their babies
Antenatal Prevalence of HBsAg in England, 2011 Antenatal Region Number tested prevalence % East Midlands 55,561 0.36 East of England 72,623 0.27 London 137,490 1.02 North East 33,311 0.19 North West 79,607 0.23 South East 105,874 0.26 South West 66,313 0.15 West Midlands 75,379 0.32 Yorkshire & 66,262 0.32 Humber ENGLAND 692,420 0.42 Source: Data Tables for National Antenatal Infections Screening and Monitoring (NAISM) Programme 2011 (HPA & NSC)
Neonatal immunisation programme objectives • Timely uptake of the full vaccination schedule • appropriate handover of mother and baby from maternity services to primary care services occurs in a timely manner • Systems are in place to support reporting of vaccination uptake to the national vaccination coverage system (COVER)
Vaccination schedule and follow-up “ For post-exposure prophylaxis in babies born to mothers infected with hepatitis B, the accelerated immunisation schedule is preferred ”. This schedule comprise a series of vaccinations as outlined above Testing for HBsAg at one year of age will identify any babies for whom this intervention has not been successful and who have become chronically infected with hepatitis B. Serology can be performed at the same time as the fourth dose is given. Any child infected with Hepatitis B needs referral for assessment and further management. Where immunisation has been delayed beyond the recommended intervals, the vaccine course should be completed. However it is more likely that the child may become infected. Thus, testing for HBsAg above the age of one year is particularly important in this instance.
Indications for HBIG in infants • HBIG is offered in addition to vaccine to babies born to higher risk mothers who are • HBeAg positive OR • anti-HBe negative • Acute hepatitis B in pregnancy OR • High viral load (if measured >10 6 ) OR • Infants with very low birth weight (< 1500g) • All babies to whom CIDSC issues HBIG are followed up with GP / Trust
Effectiveness of neonatal vaccination • Efficacy of timely vaccination: 72-92% • Booster dose at 12 months gives longer term protection • HBIG marginal impact over and above vaccination • Benefit of HBIG only in highest risk infants (a further 50% reduction)
Annual neonatal hepatitis B coverage of three doses at 12 months, England: 2006-2012 2006/07 2007/08 2008/09 2009/10 2010/11 Returns with 113 114 109 112 123 12 month data* 12 month 1372 1505 1551 1903 2008 denominator Coverage at 76.5 67.6 75.6 79.1 79.0 12 months (%) *2006/07-2009/10: n=152 *2010/11n=151
Neonatal Hepatitis B coverage of 3 doses at 12 months, Nottingham City 2006-12 2006 2007 2008 2009 2010 2011 2012 Number 15 11 18 22 16 21 17 completed 3 doses 12 month 17 12 20 24 17 24 19 denominator Coverage at 88 92 90 92 94 88 90 12 months (%)
Annual neonatal hepatitis B coverage of four doses at 24 months, England: 2006-2012 2006/07 2007/08 2008/09 2009/10 2010/11 Returns with 115 113 110 111 122 24 month data* 24 month 1210 1250 1536 2047 1940 denominator Coverage at 54.6 46.6 50.3 49.9 54.0 24 months (%) *2006/07-2009/10: n=152 *2010/11: n=151
Neonatal Hepatitis B coverage of 4 doses at 24 months, Nottingham City 2006-12 2006 2007 2008 2009 2010 2011 2012 Number 12 11 14 22 16 15 15 completed 4 doses 24 month 17 12 20 24 17 24 19 denominator Coverage at 71 92 70 92 94 63 79 24 months (%)
12-month blood test (HBsAg or anti-HBs), Nottingham City 2006-12 2006 2007 2008 2009 2010 2011 2012 Number of 16 13 20 25 18 23 28 eligible babies Number with 12 8 14 11 3 4 1 Anti-HBs result Number with 0 3 4 8 10 7 4 HBsAg result Total (%) 12 (75) 11 (85) 18 (90) 19 (76) 13 (72) 11 (48) 5 (18)
Current challenges in follow-up of at-risk infants • Incomplete reporting to COVER • Geographical variation in coverage • Lack of national data on proportion of infants tested and outcome of testing • Uptake of testing less than 50% (in high risk infants) • Difficulties obtaining venous blood samples in primary care • Referral to secondary care (additional visit)
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