1. Istituto Zooprofilattico Sperimentale delle Venezie
The Italian experience in the control of Avian Influenza applying emergency and prophylactic vaccination
Luca Busani
Istituto Zooprofilattico Sperimentale delle Venezie

2. The AI challenge in Italy
High density of susceptible species (turkeys) in a limited area (Densely Populated Poultry Area-DPPA)
Wetlands and resting sites for migratory waterfowl in close proximity of this DPPA
Several introductions of LPAI viruses from wild birds resulting in some cases in major epidemics

3. Mallard population in Italy: 110,000 birds/year
ITALY - VENETO AND LOMBARDY
Distribution of poultry holdings
Mallard population in Italy:
110,000 birds/year
@ poultry holdings
@ 95 million bird places

4. Italy: AI outbreaks from 1997 to 2005
HPAI: H5N2 8 outbreaks, backyard flocks, prompt eradication
2000 LPAI-HPAI: H7N1, total costs € 500 million
LPAI: H7N1 78 outbreaks
LPAI: H7N3 388 outbreaks
2004 LPAI: H7N3 28 outbreaks (September- November)
2005 LPAI: H5N2 15 outbreaks (April-May)
Total direct costs: 170 million euros

5. LPAI: prevention control strategies
Increase of farms bio-security level
Prompt detection of any AI virus introduction in:
Poultry
Wild birds
Vaccination (H5–H7 virus subtypes)
Reduction of farm density, mainly turkey farms (long term strategy)

6. VACCINATION AREA More than 1000 farms More than 31 million birds
Lombardia
Veneto
This is the area where the vaccination is in place since 2000, the blue line limits the vaccination area until 2004 that now is an intensive surveillance area, while the red line defines the actual vaccination area
VACCINATION AREA

7. Vaccination: data management system
Reports to decision makers
Laboratory data
Poultry populations data
Central data collection and analysis
If vaccination is to be used to complement rather than replace a stamping out
policy this raises other issues. Possibly the most important of these will be how
to identify a vaccinated flock infected with HPAI. This could be done by routine
surveillance of vaccinated flocks, either by virus isolation or by using a marker
vaccine [none are available at present] or one with a different neuraminidase to
the field virus so that cheaper serological monitoring can be done or by using
unvaccinated sentinel birds. Limited vaccination of part of the poultry industry
considered most at risk has also been suggested. For example, breeder birds that
live longer or replacement stock. However, if a stamping out policy is to be
retained such birds would still be slaughtered if they became infected with
HPAI virus. Vaccination in these circumstances would therefore be accepting
that biosecurity measures and for replacements cleaning and disinfection were
unlikely to be succesfull.
Monitoring activity
Poultry vaccination data

8. Numbers of vaccination in Italy (2000-2006)
2002
2003
2004
2005
2006
Capons
41,000
301,000
268,000
192,000
211,000
Guinea Fowls -
84,000
75,000
Cockerels
1,061,000
1,261,000
Laying hens
6,534,000
26,830,000
13,263,000
7,577,000
5,459,000
Turkeys
16,303,000
47,242,000
36,171,000
28,318,000
10,908,000
Total (doses)
23 million
75 million
51 million
36 million
17 million
Cost (€)
4 million
13 million
9 million
6 million
3 million
The other preventive measure in place is the vaccination, and the annual doses of vaccine administered in the last years ranged from 51 million to 36 million, this difference is due to the fact that in 2005 the vaccination area was reduced then a lower number of flocks were vaccinated conparing to 2004.
Vaccination-related costs: 35 million €
payed by the farmers

9. Weekly incidence rate of LPAI H7N3 outbreaks
From 31/12/02 vaccination of turkeys (H7N1)
R0=3.0
IC ( )
R0=0.6
IC ( )

10. LPAI epidemics and vaccination in Italy
emergency vaccination
preventative vaccination
c,d) poor adherence to the vaccination protocol
c) 17 flocks vaccinated only once or twice, instead of three times as scheduled;
d) all flocks vaccinated only once

11. Conclusions I
Emergency and prophylactic AI vaccination can reduce financial losses due to AI epidemics
In order to maintain trade, vaccination must be coupled with monitoring and aimed at eradication
Wild birds and backyard flocks must be included in the monitoring programs
The problems related to AI vaccines and vaccination must be considered when intervention is planned

12. This strategy must be adapted to the field conditions
Conclusion II
Control of AI in DPPAs requires a coordinated territorial strategy including surveillance, early detection and prompt intervention and vaccination should be part of it
This strategy must be adapted to the field conditions
It requires dedicated resources
The sustainability in the long period is the major drawback
The Italian situation should be compared to other DPPAs troughout the world, and in thses areas, the control of AI requires a coordinated territorial strategy including surveillance, early detection and prompt intervention. In particular, the italian experience showed that vaccination is effective if applied with the aim to eradicate the infection, but such measures require dedicated resources, and, of course dedicated funds because their effective application is expensive and the costs involve the not only producers but also the society as a whole.

13. Grazie per l’attenzione…
Luca Busani Istituto Zooprofilattico delle Venezie – CREV Stefano Marangon Istituto Zooprofilattico delle Venezie