Hepatitis E Virus Seroprevalence among Blood Donors in South West Switzerland

Annatina Kaufmann1, Alain Kenfak Foguena2, Cyril André3, Giorgia Canellini4, Philippe Bürgisser3, Darius Moradpour5, Matthias Cavassini2

1 Faculty of Biology and Medicine, Lausanne University2 Infectious Diseases Service, Centre Hospitalier Universitaire Vaudois (CHUV) and Lausanne University3 Laboratory of Immunology and Allergy, CHUV and Lausanne University

4Service Régional Vaudois de Transfusion Sanguine, Epalinges5Division of Gastroenterology and Hepatology, CHUV and Lausanne University

Introduction

Methods Here are the blood samples from today's blood donation!

Great! That’s 550 samples in five days! We can stop now.

Why 550?

We used the Lorenz formula. We aimed for a precision of 1.5% and a confidence interval of 95%. Assuming a prevalence around 3%, we estimated we would need a minimal sample size of 500 individuals.

References Country Prevalence % Year of Publication Subjects nr Laboratory testZaaijer et al, p. 826 Netherlands 1.1 1993 1275 Abbott, Diagnostic BiotechnologyZanetti and Dawson; p. 318-20 Italy 0.95 1994 948 AbbottLavanchy, Morel and Frei; p. 747-48 Switzerland 3.2 1994 94 Abbott, Western-blot assey

Thomas, p. 1244–1247 Baltimore 21.3 1997 300 Inhouse, GenelabsMateos , p. 267 - 269 Spain 2.8 1998 863 Abbott, Western-blot asseyDalekos, p. 589 - 595 Epirus, Greece 0.23 1998 2636 AbbottMeng et al, p. 117-22 USA 18.3 2002 400 InhouseBoutrouille, p. 2009-2010 N France 3.2 2007 1998 Genelabs DiagnosticsChristensen et al, p.1026-31 Denmark 20.6 2008 461 Inhouse

Dalton et al. p. 784-90 England 16 2008 500 WantaiMansuy et al, p. 289-93 SW France 16.6 2008 529 Genelabs DiagnosticDalton, p. 579–585 SW Britain 15.8 2008 487 Wantai

This Study SW Switzerland 4.9 2010 550 MP Biomedicals, a

All donorsn = 550

HEV negativen = 523 (95.1 %)

HEV positiven = 27(4.9 %)

Sex

Male 332 314 (94.6) 18 (5.4)

Female 218 209 (95.9) 9 (4.1)

ALT

≤ 60 U/L 546 519 (95.1) 27 (4.9)

61-100 U/L 4 4 (100) 0 (0.0)

Age

18-30 6 6 (100.0) 0 (0.0)

31-50 187 178 (95.2) 9 (4.8)

51-70 320 303 (94.7) 17 (5.3)

>70 37 36 (97.3) 1 (2.7)

HEV PCR is not yet commercially available as a screening tool. Therefore no effective screening of active HEV is performed on blood donor samples.

England:13.5%

Denmark:20.6%

France:13.5%

All drawings by Annatina Kaufmann, principal investigatorFinancial and spiritual support: M. Cavassini

a : Formerly Genelabs Diagnostics, Singapore

A high HEV seroprevalence has been reported among blood donors of several European countries

But what about other developed countries?

I would like to donate blood.

Here’s the questionnaire you have to complete and the consent form to sign.

To determine HEV seroprevalence among blood donors in South West Switzerland.

Over 90% of the pork consumed in Switzerland is

produced in Switzerland.

Discussion

In comparison with several other developed countries, seroprevalence in Switzerland remains low. However, comparison between studies remains difficult due to differences in the demographics of the populations studied and the HEV antibody detection assay used.

I agree to my blood donation or some components being used for medical

research.

Study Aim

Hepatitis E virus (HEV) emerged as an autochthonousfood-borne disease in developed countries, transmittedmainly through consumption of undercooked meat.Pigs and other mammals are considered the reservoir ofHEV in regions where it is not endemic among humans.

Switzerland :?

332 men (60.4%) and 218 women (39.6%), altogether 550 blood donors. Median age was 55 years ( IQR 46-63 years).

So who were these blood donors?

27 samples tested positive for IgG anti-HEV. That’s a

seroprevalence of 4.9%

And did you find any sign of past infection with your IgG diagnostic kit?

All 550 Blood samples were screened for the presence of anti-HEV IgG (MP Diagnostics HEV ELISA) in the Immunology Laboratory of the CHUV.

Results and Characteristics of Study Group

HEV Seroprevalence among Blood Donors

HEV seroprevalence in Switzerland is low compared to several other European countries

HEV diagnostic assays may have different sensitivity/specificity which may hinder comparisons

HEV prevalence among pork and other potentially infected animal species in Switzerland needs to be assessed

Today no effective screening of active HEV is performed on blood donor samples

Conclusions