1. Francesco Prandini – DVM
MERIAL Avian Technical Manager EMEA
Protection against
Salmonella infection
using vaccines
Baromfiágazat annual Seminar 2013
Budapest, October 1st
2013

2. Introduction
• Salmonella spp is one of the major causes of
food-borne illness in humans
• High prevalence of Salmonella in poultry
• Chicken and chicken products are the most
frequent sources of zoonoses
World Poultry - Dec 29,
2011

3. Salmonella
• Motile non-host-specific serovars:
>2000 serovars nearly ubiquitous in wild and
domestic animals
• Very common but seldom cause clinical
disease
• More often, asymptomatic persistent
colonization of the intestinal tract
• “Paratyphoid” infections of
poultry and zoonoses

4. Zoonoses cases in humans in 2011

5. Salmonella epidemiology
• S.Enteritidis (SE) and S.Typhimurium (ST)
are the serovars most frequently associated
with salmonellosis in humans through the
food chain
• Commonly asymptomatic colonization of
chickens in the intestinal tract
• Egg shell contamination
• SE can infect eggs internally

6. Distribution of food vehicles in outbreaks
caused by S.Enteritidis in the EU, 2011

7. Distribution of the 10 most common Salmonella
serovars in humans in the EU, 2010-2011

8. Salmonella in human cases, eggs and laying hens
and the number of Salmonella outbreaks caused
by eggs within the EU, 2007-2011

9. Breeders
Gallus gallus
Laying hens
Gallus gallus
Broilers Turkeys
S.Enteritidis S.Enteritidis S.Enteritidis S.Enteritidis
S.Typhimurium S.Typhimurium S.Typhimurium S.Typhimurium
S.Infantis
*All salmonella serovars with public
health significanceS.Hadar
S.Virchow
Serovars* with established targets for reduction of prevalence in the EU

10. Salmonella control in Chickens
• Control of biological reservoirs:
– Breeders
– Replacement flocks
– Rodents
– Red mites
• Rigorous biosecurity measures
• Slaughtering of positive Breeders/Layers flocks
• Competitive exclusion and Probiotic effects
• Vaccination
• Comprehensive programs of risk reduction

11. Salmonella VACCINATION
Specific protection against S. serovars
Both Live and Killed vaccines have been
associated with significant protection
An important component of SE-ST plans of
risk reduction in Layers and Breeders
Farm-tailored vaccination strategies

12. Salmonella VACCINES
Live attenuated vaccines:
• Mass application
• Mainly local immune response
Inactivated vaccines:
• Individual s.c./i.m. injection
• Mainly humoral immune response
Vaccination programs:
• Live
• Inactivated
• Live + Inactivated

13. Live VACCINE
 A live attenuated vaccine against S. Enteritidis
 Adenine - Histidine double auxotrophic strain
 Drinking water administration
 2 or 3 doses tailored programs
 Early and long-lasting protection
 Easy and rapid field strains differentiation
Gallivac Se strain Field strain

14. Challenge trial with GALLIVACChallenge trial with GALLIVAC®®
SeSe
Oral Vaccination @ 2,16 & 114 days of age, and
challenge with 5 billion pathogenic SE bacteria
into the crop of each bird at 78 weeks of age.
Number of bacteria per gram of tissue 7 days after challenge.
0
10.000.000
20.000.000
30.000.000
40.000.000
Caecum @ 79 weeks
Un vaccinated Gallivac Se
0
50
100
150
200
250
300
Liver at 79 weeks

15. Inactivated VACCINE
 A bivalent inactivated vaccine against S.Enteritidis
and S.Typhimurium for pullets
 Innovative manufacturing method to preserve
antigenicity
 0.3 ml emulsion dose s.c. or i.m.
 2 doses program: from 6 wks & 16 wks
 Rapid and lasting protection
Classical processControlled nutrient fermentation

16. Blood sampling
Comparison of inactivated vaccines
Gallimune®
Se+St
W10
W16
W16
W10
W30
Se+St Al hydroxide
W16W10
Control group unvaccinated
W30
W30
G 1
G 2
G 3

17. Antibody titres at 30 weeks

18. Gallimune®
Se+St
W10
Competitor vaccine
W16
W16
W12
Challenge
W27
W27 +4 days
+4 days
Ovary
sampling
60 pullets
SE PT4 oral challenge
Challenge 1: ovary contamination

19. Challenge trial with Gallimune®
Se + St
Results of isolation of S. Enteritidis PT4 in the ovaries of birds 4
days post oral challenge at 27 weeks of age.
-90%

20. • Groups of 60 pullets:
– Vaccinated at 10 & 16 weeks of age with
Gallimune Se + St - 0.3 ml
– 12 & 16 weeks with reference vaccine - 0.5 ml
– Controls
– 29 weeks of age: oral challenge with ST
– 31 weeks of age: oral challenge with SE
– Caecal droppings collected 4 days post challenge
Challenge trial with Gallimune®
Se + St

21. Gallimune
®
Se+St
W10
W16
W16
W12
W29
W29
+4 days
Challenge 2: fecal shedding
Other vaccine
• 29 weeks  ST challenge oral route
• 31 weeks  SE challenge oral route
+4 days
Gallimune®
Se+St
Reference vaccine
Challenge Faeces sampling

22. Challenge 2: fecal shedding

23. Challenge 2: fecal shedding

24. SINGLE or COMBO vaccination programs
PROTOCOL
Age of chicks Group 1 Group 2 Group 3
Day 1
Gallivac Se
drinking water
Gallivac Se
drinking water
Controls
Day 42
Gallivac Se
drinking water
Gallivac Se
drinking water
---
Week12
Gallivac Se in
drinking water
--- ---
Week 4
Gallimune Se+St
im breast
injection
---
Week 52
challenge with
SE or ST
challenge with
SE or ST
challenge with
SE or ST

25. Challenge study PROTOCOL
• Lohmann Brown Commercial layers
• Oral challenge with 109
CFU of SE or ST
• Birds sacrificed 7 days after challenge
• Enumeration of SE and ST cells per g. of
caecal content

26. 52 weeks - SE challenge

27. 52 weeks - ST challenge

28. Conclusions
 Salmonella requires comprehensive control plans
 Vaccination is an important component
 Live and inactivated vaccines has specific features
 Combined vaccination programs consolidate
advantages from both
 Farm-tailored vaccination strategies are required

29. Thanks for
your attention