Download Study on HEV Vaccination Approach

Study on HEV Vaccination Approach in
Swine for Public Health protection
Jeanette van der Goot, Jantien Backer, Leo van Leengoed, David Rodriquez
Lazaro, Franco Ruggeri, Alessandra Berto, Francesca Martelli, Ivo Pavlik,
Wim H. M. van der Poel
Pig finishing farm industry
Weaning
finishing farm
Slaughter
10 weeks of age
28 weeks of age
± 25 kg
± 110 kg
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SEIR Model for HEV in pigs
susceptible
latently
infected
infectious
recovered
Experimental data (Bouwknegt et al. 2007):
Transmission parameter: 0.66 infections per day
per infectious animal
Latent period: 3 (0.8 – 6.3) days
Infectious period: 25.8 (7.0 – 54) days
3
proportion of population
Age distribution at high transmission
R0 = 17
susceptible
latently infected
infectious
recovered
total
weeks of age
age at entry
age at slaughter
4
proportion of population
Age distribution at lower transmission
R0 = 2.6
susceptible
latently infected
infectious
recovered
R0 = total
2.6
weeks of age
age at entry
age at slaughter
5
Infection dynamics at high transmission
number of animals
R0 = 17
susceptible
latently infected
infectious
recovered
total
time (days)
time of infection
6
Infection dynamics at lower transmission
number of animals
R0 = 2.6
susceptible
latently infected
infectious
recovered
total
time (days)
time of infection
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Infectious period distribution
uncensored
censored
infectious period (days)
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Partners/ sampling countries




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United Kingdom
Czech Republic
Spain
Italy
Netherlands
VLA (data available)
VRI
ITACyL
ISS
Utrecht University
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Farm sampling schedule




One HEV-positive farm
per country
Sampling by taking anal
swabs
Sampling of 2 pigs per
pen
Total nr of samples in a
farm of 10 compartments
incl. 10 pens: 2 * 10 * 10
= 200 samples
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Time schedule task 6.4

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Farm sampling:
Testing of samples:
Data evaluations:
Modeling:
Publication:
April 2009 – June 2010
June 2009 – August 2010
August 2010 – Dec 2010
Jan 2011- Feb 2011
March 2011- April 2011
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