This presentation summarizes what is known about hepatitis E virus (HEV) in Denmark. HEV infection has not been highly monitored in Denmark but will become a notifiable disease starting next year. Since 2010, HEV diagnosis has been performed at Statens Serum Institut (SSI), where the median age of cases is 43 years and males make up 50.1% of cases. Several studies found high prevalence of HEV in Danish pig and mink populations. Seroprevalence studies among farmers, blood donors, and prisoners show declining levels of hepatitis E antibodies over time, from around 50% in 1983 to around 20% in 2003 and 11% in 2013, not indicating a rise in HEV cases or exposure.

1. Hepatitis E
and what we know about the situation in
Denmark
Steen Ethelberg
Statens Serum Institut
Senior Researcher, Head of unit
set@ssi.dk

2. This short presentation…
• Limited amount of data ~15 pub papers
I’ll go through:
• Surveillance
• Data on number of cases
• Animal and environmental studies
• Serological population studies.

3. HEV in DK
• Hepatitis E virus infections have so far not
been high on the agenda in Denmark
• Not notifiable
• …. But will be from next year!
• Only lab diagnosing is at the SSI
• Awareness probably limited among clinicians.

4. HEV diagnostic in Denmark
• Diagnosed in Denmark since 2000
• From 2000 to 2009 the samples were sent to
Smidttskytsinstituttet in Sweden
• Published case series (1993-2007):

5. Since 2010 diagnosed at SSI
Median age 43 years; Male gender 50.1%
Data: Hanne Thang Vestergaard, Vir Dept, SSI
Test/
patient
2010 2011 2012 2013 2014* Total
Patients
tested
302 293 340 475 162 1572
Samples
tested
327 426 473 635 234 2095
1st IgM
pos
9 21 13 21 9 73
1st IgG
pos
29 40 39 57 24 189
Pos IgM,
IgG and
PCR
4 13 7 6 2 32

6. Animal and environmental studies
 Breum SØ, Hjulsager CK, de Deus N, Segalés J, Larsen LE.
Hepatitis E virus is highly prevalent in the Danish pig
population.
Vet Microbiol. 2010
 Krog JS, Breum SØ, Jensen TH, Larsen LE.
Hepatitis E virus variant in farmed mink, Denmark.
Emerg Infect Dis. 2013
 Krog JS, Larsen LE, Schultz AC:
Enteric porcine viruses in farmed shellfish in Denmark.
Int J Food Microbiol. 2014
 Krog JS et al
Leaching of viruses naturally occurring in pig slurry to
field drains and their correlations with other
microorganisms. Submitted

7. • Faecal samples from 97 pigs, 1–5 months of age
• Analysed for HEV RNA with RT-PCR assay
• HEV prevalence: 55% and 50% for herds and animals, respectively.
• Sow herds: IgG prevalence of 92% ; correspond to 73% of the sows.

8. Seroprevalence studies
1. Christensen PB, Engle RE, Jacobsen SE, Krarup HB, Georgsen J, Purcell RH.
High prevalence of hepatitis E antibodies among Danish
prisoners and drug users. J Med Virol. 2002
2. Christensen PB, Engle RE, Hjort C, Homburg KM, Vach W, Georgsen J,
Purcell RH.
Time trend of the prevalence of hepatitis E antibodies
among farmers and blood donors: a potential zoonosis in
Denmark.
Clin Infect Dis. 2008
3. Holm DK, Moessner BK, Engle RE, Zaaijer HL, Georgsen J, Purcell RH,
Christensen PB.
Declining prevalence of hepatitis E antibodies among
Danish blood donors. Transfusion. 2015

9. The prevalence of anti-HEV IgG was:
• 50.4% among farmers,1983 (291 samples)
• 32.9% among donors, 1983 (169 samples)
• 20.6% among donors, 2003 (461 samples).

10. Method:
• NIH in-house ELISA; recombinant ORF2 protein
• Sensitivity of 96%, specificity of 98%, good test at the time.
Correlated with increasing age in all groups
Questionnaire, corr. with: Male sex, children, HAV, horses...

13. In conclusion
• Increasing awareness
– Notifiable from 2016
– Case definition to come
– More clinical labs to offer analysis
• Presently very few known cases
• Repeated seroprevalence studies:
– 1983: 33%; 2003: 21%; 2013: 11%
• Not indication of rise in cases/exposure.

14. THANKS!