Hepatitis E Virus in England and Wales

Hepatitis E Virus in England and Wales

Samreen Ijaz

Blood Borne Virus Unit

Virus Reference Dept

2

HEV in England and Wales

• New understanding of HEV infections in our population

• Established national programme of enhanced surveillance in 2003 (E&W)

• Viral hepatitis including Hepatitis E is a notifiable disease

• Developed case definitions and testing strategies (acute cases and for the

immunosuppressed)

• Recognise HEV as the most common cause of acute hepatitis in England and

Wales

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• PHE case control study – (2012)

• 25 cases/75 matched controls

• food based questionnaire

• analysis suggests an association between the consumption of pork based

products and HEV infection

• Berto et al., 2012 provided evidence of HEV contamination in the

pork production chain

• 10% of sausages at point of sale HEV RNA positive

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Investigating transmission routes in England

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Imported versus indigenous infection in England/Wales

0

100

200

300

400

500

600

700

800

900

1000

2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014

Frequency

Year

Total

Indigenous

Travel1:7000

1:2850

Incidence in

blood donors

Molecular epidemiology

(2003-2013)

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Group 2

2010-2013

Group 1

2003-2009

Nucleotide Subsitution per 100 residues

032.2 51015202530

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Proportion of group 1 and 2 sequences - 2003-2014

0

50

100

150

200

250

300

350

400

2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014

Freq

uen

cy

Year

Group 2

Group1

Change in the magnitude of risk

• Rise is case numbers associated with the emergence of a clade of

viruses not commonly circulating prior to 2010

• are these dominant viruses more transmissible?

• are these dominant viruses of different pathogenicity?

• How and WHERE have the risk factors changed?

• Changes in farming practices or animal husbandry?

• Changes in food processing or importation of meat?

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2013 UK Pig Abattoir survey

• 93% seroprevalence rate in UK pigs

• ~6% viraemic at time of slaughter

• Pig viruses fall into group 1 of genotype 3

• 2/3rds of human infection in England fall into group 2 viruses of genotype 3

• Source of infection in or out of the UK?

• Cross European studies with a view to sequence data linkage and sharing

across human and pig sequences.

• Define the epizoology across Europe.

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HEV and Blood Safety

• HEV RNA incidence found to be 1:2850 in donors

• Follow up investigations found 42% transmission rate from HEV-infected

blood components to recipients

• Plasma HEV viral load important factor for transmission

• Indication that products with lower plasma content less likely to be

associated with transmission

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Public health implications of HEV have grown

• Remit goes beyond the recognition and characterisation of acute HEV

infections

• Recognition of chronic HEV infections in the immunosuppressed population

• PHE establishing a register to better understand and monitor these infections

• 60 cases of chronic hepatitis E

• Haem-oncology/HSCT patients

• SOT recipients

• HIV-infected individuals

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HEV summary

• Now recognised as a widespread zoonosis associated with rolling infections in

England and Wales

• Currently in a period of heightened HEV activity; associated with the emergence

of a novel phylotype

• Europe wide collaborations to link HEV sequences from both human and pig

populations to inform options for control

• UK introducing HEV screening for donations given to SOT and SCT patients to

reduce exposure

• UK to consider how to identify and mitigate HEV risks in immunosuppression

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AcknowledgementsPublic Health England NTMRL, NHSBT, Colindale

Richard Tedder Alan Kitchen

Dilys Morgan Ines Ushiro-Lumb

Bengu Said Pat Hewitt

David Brown Su Brailsford

Poorvi Patel

Becky Haywood Colleagues at APHA

Rachel Brett Colleagues at NHSBT

Steve Dicks Colleagues at BPEX

Kate Tettmar