Hepatitis B – Monitoring the infant hepatitis B

immunisation programme and provision of a

Dried Blood Spot testing service

Mr Philip Keel

Scientist (Epidemiology)

Immunisation Hepatitis and Blood Safety Department, National Infection Service, PHE Colindale

30th October 2015

Global prevalence of

chronic hepatitis B, 2006

Source: CDC, Yellow Book

UK epidemiology of hepatitis B

• Low prevalence: 0.3-0.4%

• Incidence of acute hepatitis B low and stable (lab reports): 0.77 per 100,000 (2013)

• Heterogeneous distribution of risk

Adults

Chronic burden mostly among migrants who acquired infection during childhood in country of origin

Transmission: sex, injecting drugs

Children

Transmission: mother to child, horizontal, exposure overseas

Selective Vaccination Programmes 3 Hepatitis B - Dried Blood Spot Testing

Risk of mother to child transmission

• Risk of mother to child transmission high around birth (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

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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)

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UK hepatitis B immunisation policy

• Selective: vaccination of high risk groups

• Since April 2000

• All pregnant women offered antenatal screening

• All infants born to hepatitis B positive mothers receive a complete course

of hepatitis B vaccine (0,1, 2 & 12 months)

• At around 12 months infants also tested for evidence of chronic infection

• If infected infant referred early to specialist for assessment and care

• Co-ordinated management and delivery of programme

• Regular monitoring and local audits

COST SAVING TO THE NHS

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Prevalence of hepatitis B among

pregnant women in England, 2013

Region Number tested Antenatal

prevalence %

East Midlands 40,315 0.26

East of England 80,770 0.44

London 148,684 1.46

North East 30,702 0.17

North West 91,970 0.34

South East 105,810 0.29

South West 57,286 0.16

West Midlands 66,992 0.55

Yorkshire & Humber 68,301 0.32

ENGLAND 690,760 0.58

Source: Data Tables for National Antenatal Infections Screening and Monitoring (NAISM) Programme 2013 (HPA & NSC)

Indications for hepatitis B immunoglobulin

(HBIG)

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Irrespective of mother’s markers, if infant’s birth weight is <=1500grams – requires HBIG

Source; Green Book, Immunisation against infectious disease

Hepatitis B - Dried Blood Spot Testing

Monitoring the infant hepatitis B vaccination

programme

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PHE enhanced surveillance of high risk infants

PREGNANCY

•HBIG issue received after antenatal booking

•HBIG sent 6-8 weeks before EDD

•Maternal HBV markers collected

BIRTH

•HBIG and 1st dose of vaccine administered

•Birth details collected

•Maternal antiviral treatment data collected

INFANT

•Reminder letters to GP / paediatrician before each vaccine dose

•Vaccination uptake data collected

1 YEAR OLD

•DBS kit or venepuncture kit sent to GP /paediatrician

•Infants with chronic infection identified

•Putative vaccine failure investigated

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Challenges in follow-up of at-risk infants

Data

• Incomplete reporting to COVER

• Denominator and numerator discrepancies

• Lack of outcome info on low-risk infants

Technical

• Difficulties obtaining venous blood samples in primary care: additional visit to secondary care for testing

Communication

• Health practitioner engagement and patient understanding

Logistical

• Mobile population

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National dried blood spot (DBS) testing service

• Aim: improve uptake of 12 months testing by providing alternative to venepuncture

• Intended use in primary care (no need for hospital referral)

• Dried blood spot testing (DBS) to test for evidence of infection

• Validated assay to detect HBsAg and anti-HBcore antibody

• DBS kits provided by and tested at PHE-Colindale free of charge

• Request form collects maternal hepatitis markers and infant vaccination history

• Results of testing to requesting clinician (GP) and nominated coordinator (cc to HP Team)

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DBS Kits

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www.gov.uk/government/collections/hepatitis-b-guidance-data-and-

analysis#infants-born-to-hepatitis-b-infected-mothers

Hepatitis B - Dried Blood Spot Testing

Implementation of DBS service

• Pilot

• Scheme launched September 2013

• DBS Training materials

• YouTube video

• Pictorial instructions

• Webpage http://www.hpa.org.uk/Topics/InfectiousDiseases/InfectionsAZ/HepatitisB/NationalHepatitisBDriedBloodSpotService/

• Information for parents and for coordinators

• Information for joining the scheme

• Coordinators can enrol via website and email hepatitisbbabies@phe.gov.uk

• Data collection and feedback

• Data requirements to interpret test and evaluate program

• Data return to coordinators

• Round table discussion

• Bulletin –coming soon

Other initiatives to improve infant outcome

• Contribute to evidence base for interventions to prevent MTCT

through follow up of high risk infants

• Birth DBS to determine if infection at 12 months is due to true vaccine

failure or in utero transmission

• Link in with NSC/UCL audit of management of hepatitis B pregnant

women to provide outcome data on infants

• Mapping neonatal hepB pathways - with screening and immunisation

teams (NHSE) and Health Protection teams (PHE)

• Hepatitis B in England report…coming soon

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Universal hepatitis B infant immunisation

JCVI recommendation (October 2014): a universal infant

immunisation programme for hepatitis B should be

introduced if can be procured at a cost-effective price

Acknowledgements

Samreen Ijaz

John Parry

Justin Shute

Screening and Immunisation Teams

Health Protection Teams

DBS coordinators

Sharon Webb

Glenn Armitage

Sema Mandal

Matthew Olley

Gayatri Amirthalingam

Mary Ramsay

Miranda Mindlin

Sarah Collins

Yojna Handoo-Das

Darshna Makwana

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