BASELINE STUDY ON THE PREVALENCE OF SALMONELLA IN LAYING FLOCKS OF GALLUS gallus IN ITALY

Transcription

1 BASELINE STUDY ON THE PREVALENCE OF SALMONELLA IN LAYING FLOCKS OF GALLUS gallus IN ITALY FINAL REPORT According to Annex I of the technical specifications (SANCO/34/2004), in Italy 431 holdings of laying hens had to be sampled. This number has been stratified at a national level, in order to define the number of holdings to be sampled in each region. The calculation (annex 1) has been transmitted to the local authorities involved, which have the duty of organising the sampling activity. In October 2004 the National Reference Laboratory for Salmonella (NRL) has organised a workshop for the Regional Veterinary Services and for the laboratories possibly involved in the study, in order to present the programme and to describe in detail the sampling procedures and the laboratory methods to be used during the monitoring programme. A detailed Standard Operating Procedure (SOP) has been distributed to the national public laboratories (Istituti Zooprofilattici Sperimentali), that have been appointed by the Ministry of Health to perform the analysis. In Italy in fact the official control in the veterinary field (animals, food of animal origin) is carried out by Istituti Zooprofilattici Sperimentali (IZS), which are part of the National Health system, and are present on all the national territory with 10 central centers and numerous peripheral laboratories at provincial level. All the laboratories are accredited according to ISO EN These laboratories have a good experience in the use of MSRV for the isolation of Salmonella, since this is the method officially used for the isolation of salmonella from shellfish. All the strains isolated during this programme have been sent to the NRL for serotyping, antimicrobial resistance analysis and phage typing of S. Enteritidis and S. Typhimurium. A selection of these strains (n = 16) have been sent to the CRL-Salmonella in Bilthoven; only typable strains have been sent, since no untypable isolates were available. All the results were confirmed by CRL. A database in electronic format has been produced and distributed to all the organisations involved. Through this database all the relevant information requested by the Commission have been collected; each Region has sent its own database to NRL-Salmonella (Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Padova), where a first control on data conformity has been performed, and additional information have been requested when necessary. After this validation, the databases have been sent to the National Reference Laboratory for Epidemiology (Istituto Zooprofilattico Sperimentale dell Abruzzo e del Molise, Teramo), which was in charge of transmitting the information to the Commission, using an XML format.

2 At the end of study, 381 holdings have been sampled. At the national level, 113 holdings resulted positive for Salmonella spp. (29,7%), 16 for S. Enteritidis (4,2%) and 14 for S. Typhimurium (3,7%). All the details concerning regional distribution of samples and the results obtained are reported in Annex 2.

3 Annex 1 SAMPLING SCHEME LAYERS (Decision 22/IX/2004 C(2004) 3512 def.) sampling scheme >30000 TOT Abruzzo Basilicata Calabria Campania Emilia romagna Friuli Venezia Giulia Lazio Liguria Lombardia Marche Molise Piemonte Puglia Sardegna Sicilia Toscana Trentino Alto Adige Umbria Valle d'aosta Veneto Italy

4 Annex 2: results

5 Number of tested holdings and percentage of holdings positive for Salmonella spp. in each month ,0% 45,0% ,0% no. tested holdings ,0% 30,0% 25,0% 20,0% 15,0% % positive 20 10,0% 5,0% 0 Nov-2004 Dec-2004 Jan-2005 Feb-2005 Mar-2005 Apr-2005 May-2005 Jun-2005 Jul-2005 Ago-2005 Sep-2005 Oct-2005 Tested holdings % 0,0%

6 Number of tested holdings and percentage of holdings positive (± 95% confidence limits) for Salmonella spp. by size ,0% 90,0% ,0% 80 70,0% no. tested holdings 60 60,0% 50,0% 40,0% 40 30,0% 20 20,0% 10,0% 0 below_ >=30000 Unknown Holding size Tested holdings % l.c.l. u.c.l. 0,0%

7 Serovar Number of positive holdings % S Enteritidis 16 9,3% S Typhimurium 14 8,1% S Hadar 14 8,1% S Infantis 12 7,0% S Bredeney 11 6,4% S Mbandaka 9 5,2% S Kentucky 7 4,1% S Thompson 6 3,5% S Virchow 5 2,9% S Livingstone 5 2,9% S Cerro 5 2,9% S Braenderup 5 2,9% S Worthington 4 2,3% S Montevideo 4 2,3% S Liverpool 4 2,3% S Derby 4 2,3% S Agona 4 2,3% S Senftenberg 3 1,7% S Isangi 3 1,7% S Corvallis 3 1,7% S Rissen 2 1,2% S Newport 2 1,2% S Muenchen 2 1,2% S Llandoff 2 1,2% S Kedougou 2 1,2% S Enterica 2 1,2% S Blockley 2 1,2% S Anatum 2 1,2% S Altona 2 1,2% S Yoruba 1 0,6% S Tennessee 1 0,6% S Senftemberg 1 0,6% S Schwarzengrund 1 0,6% S Paratyphi b 1 0,6% S Ordonez 1 0,6% S Nuovo sierotipo 1 0,6% S Nigeria 1 0,6% S Lexington 1 0,6% S Jerusalem 1 0,6% S Haardt 1 0,6% S Goldcoast 1 0,6% S Glostrup 1 0,6% S Give 1 0,6% S Deby 1 0,6% S Coeln 1 0,6% TOTAL ,0%