tatjana tallo 1,2 , valentina tefanova 1 , tatjana plahhova 3 ,
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HCV SUBTYPES DISTRIBUTION IN ESTONIAN BLOOD DONORS , 2007-2009. Tatjana Tallo 1,2 , Valentina Tefanova 1 , Tatjana Plahhova 3 , Tatiana Kuznetsova 1 , Ljudmilla Priimägi 1 , Helene Norder 2 1 - National Institute for Health Development, Tallinn, Estonia - PowerPoint PPT PresentationTRANSCRIPT
Tatjana Tallo1,2, Valentina Tefanova1, Tatjana Plahhova3, Tatiana Kuznetsova1, Ljudmilla Priimägi1, Helene Norder2
1 - National Institute for Health Development, Tallinn, Estonia2 - Swedish Institute for Communicable Disease Control, Stockholm, Sweden
3 - North Estonia Medical Centre Blood Centre, Tallinn, Estonia
HCV SUBTYPES DISTRIBUTION IN ESTONIAN BLOOD DONORS, 2007-2009
10th ANNUAL CONFERENCE OF NEW VISBY NETWORK ON HEPATITIS C RIGA, FEBRUARY 10-12, 2013
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
0
50
100
150
200
250
300
350
400
17 24
The number of acute hepatitis C cases in Estonia, 1993–2012
HC
V re
port
ed c
ases
, abs
367
Introduction of HCV registration
Increasing nr of IDUs
HAV outbreak
HIV epidemic
PegIFN + ribavirin treatment
Data source: Health BoardAdopted: Dept of Virology, NIHD
Chronic HCV infection, Estonia, 2004-2011
2004 2005 2006 2007 2008 2009 2010 2011
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100% Acute viral hepatitis
Chronic HCV
Chronic HBV
Data source: Health BoardCVH became a notifiable since 1998From 2004 – according to etiology
years
years
I
ncid
ence
per
100
000
pop
ulat
ion
2010 – 246 cases2011 – 190 cases
14.2
18.4
Up to now, the quality of donor’s blood is an issue of high importance.
The safety of the blood supply can be estimated by monitoring the prevalence of viral markers in the blood donor’s population.
The other approach to increase quality of donor’s blood is to improve the quality of blood donors and one of the solutions is the replacement of paid blood donation with free blood donation system.
WHO goal: Towards 100% voluntary non-remunerated blood donation by 2020
Blood donation in Estonia, 1998-2009Paid blood donation: before 1998Transitional period: from 1998 to 2004
• From 1998 – only Rh-neg (3.3-4.0%) apheresis donors were paid• From 2002 – only plasmapheresis donors (1.8-2.0%) remained paid • From 2004 – all blood donations became free
1999
2001
2003
2005
2007
2009
0
5000
10000
15000
20000
25000
30000
35000
DonationsDonorsFirst time donorsRepeated donors
- 340551
- 204559
- 57663
- 146896
Data source: North Estonia Medical Centre Blood CentreAdopted: Dept of Virology, NIHD
The total number of blood donors, donations, and the number of repeated donors increased, respectively, in 1.2, 1.1 and 1.4 timesThe ratio between males and females remained similar: M:F=0.9 in average
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
Anti-HCV prevalence in blood donors, Estonia, 1995-2009
North Estonia Medical Centre Blood CentreAdopted: Dept of Virology, NIHD
Introduction of free donation
%
HCV RNA
Lack of data
1997-2001 = 0.80%
2002-2006 =0.34%
<0.1%
transitional period
No recent data has been reported on molecular epidemiology of HCV in Estonian blood donors
The study objectives
To investigate the distribution of HCV genotypes in anti-HCV positive blood donors diagnosed in 2007 to 2009
To compare the relative HCV genotypes distribution in blood donors before and after introduction of free donation
To determine genetic relatedness of isolates from Estonian blood donors with isolates from previously studied population groups in Estonia and other parts of the world
Material and methods
• 61 serum samples (47%) collected from 131 anti-HCV positive blood donors
during 2007-2009 at North Estonia Medical Centre Blood Centre, Tallinn, were used as a source of HCV RNA
• Sex distribution: 36 males, 25 females
• Mean age: 31.5±10.2 years; range: 18-57 years
• Detection of serum HCV RNA has been performed by PCR forwarded to the 5’-UTR region
• The HCV subtypes were determined by amplification sequencing within NS5B region and phylogenetic analysis
2k/1b 1,0%1a 1,0%
3a 21,4%
1b 76,7%
HCV studied population, n=103
HCV molecular epidemiology in Estonia, 1994-2004
T.Tallo, JMV, 2007
First 2k/1b recombinant strain outside Russia
Study population:• Infectious disease clinics, pts;• Hemodialysis pts;• Oncohematology pts (chidrens);• Health Care Workers
Similarity: mainly with strains from St.-Petersburg, Siberia and Uzbekistan
1b 69,1% 1a 5,5%
3a 20%
2a 3,6%2c 1,8%
Blood donors, n=61 (2007-2009)
Results: HCV subtypes distribution
All 1a subjects were isolated from first-time donors, males, mean age 28 yrs, from Tallinn
3a 24,6%
1b 68.2%
2a 1,5%2c 4,6%
Blood donors, n=100 (1998-2004)
Mean age 28yrs ; 69% males
85% - first time donors
Mean age 31.5yrs; 59% males
88% - first time donors
1b, 3a, 2a and 2c strains were intermixed with previously published Estonian strains and were similar to strains from Siberia and St.-Petersburg area
T.Tallo, JMV, 2007
Results: Phylogenetic analysis
1b, 3a, 2a and 2c strains were intermixed with previously published Estonian strains sharing, in general, similarity with strains from St.Petersburg and Siberia.
Three 1a starins have been found in 2 different clades: Two strains isolated from blood donors in 2007 were similar to strains from USA and Germany.
One strain obtained from blood donor in 2009 was similar to strains from Portugal.
1a strain from our previous study isolated from HCV patients with unknown risk factor in 2001 was similar to strains from St. Petersburg.
Conclusions
Subtype 1b is still the most prevalent HCV subtype found in Estonian blood donors.
The relative distribution of HCV subtypes in blood donors before and after the introduction of free donation was similar; two separate introduction of 1a HCV strains have been observed in Estonian blood donor’s population during study period.
Changes of the HCV subtype distribution in the Estonian blood donors reflected recent changes in relative distribution of the HCV subtypes in the Estonian IDUs reported previously.
We suggest that blood donors can be used as a representative part of “a general population” for study on HCV Molecular epidemiology in Estonia.
Acknowledgment
Health Board (former Health Protection Inspectorate) Jevgenia Epshtein, Chief Specialist, epidemiologist
National Institute for Health Development, Department of VirologyIrina Reshetnjak, scientist
Study was supported by grants from Swedish Institute, nr. 01348/2007 and nr. 00747/2010.