1. An Outbreak of Salmonella Typhimurium DT49 in Ireland C. O’ Hare H. Pelly P. McKeown M. Di Renzi G. Corbett-Feeney M. Cormican

2. Map & Key County Dublin County Longford County Roscommon 1 dot = 1 case of Salmonellosis (random placing)

3. Case Definitions Probable case: Diarrhoea plus or minus one or more of : fever, headache, abdominal pain, nausea, vomiting, confusion, bloody stools AND ate at restaurant X between the 4 th and the 19 th April 2004 Confirmed case: criteria of a probable case and had laboratory confirmation of Salmonella Typhimurium

4. Case Ascertainment All patients with Salmonella Typhimurium infection in Ireland with date of onset of symptoms between the 4 th April and the 21 st April, were asked if they had eaten in restaurant X. Contacts of cases who had also eaten at the restaurant were interviewed and stool samples were obtained. Characteristics of Cases 9 confirmed cases, 1 probable case 8/10 female : (1 food handler) Mean age 36.5 years (range 8-77 years) Hospital admission required in 3/10 cases One isolate was invasive and was cultured from blood No fatalities

5. Epidemic curve, by date of onset of symptoms

6. ChickenStuffingPepper sauce Red pepper sauceMeringueManufactured ice-cream TiramisuEgg whiteWhipped cream Raw shelled eggsColeslaw Foodstuffs analysed by Food laboratory from Restaurant X Epidemic curve, by date of eating in restaurant X

7. Case control Studies 10 Cases (9 confirmed) 26 controls (including) 13 controls (asymptomatic contacts who dined in restaurant X during the period 4 th to 19 th April) 13 staff members (asymptomatic contacts who confirmed that they consistently ate on the premises)

8. FoodstuffCasesControlsORP value Tiramisu5/104/265.50.04 (5 th and 11 th ) Tiramisu3/70/9///0.06 (11 th ) Foods containing9/1016/265.60.1 Liquid egg (5 th and 11 th ) Foods containing7/74/9///0.03 Liquid egg (11 th ) Relationship between Food exposure and salmonellosis (Univariate)

9. Salmonella Reference laboratory Serology (Kauffmann-White scheme) Phage type (Anderson scheme) Antimicrobial susceptibility (Disk Diffusion: NCCLS) PFGE (Pulse Net, CDC, USA) Plasmid profile (Kado and Liu) 9/10 patient isolates were received by NSRL Microbiology

10. Antimicrobial Susceptibility Isolates tested against a panel of 14 antimicrobials Results: 8 isolates were susceptible to all antimicrobials tested 1 sample contained 2 isolates with different antibiograms A : ampicillin, streptomycin and kanamycin resistant B: fully susceptible

11. S. Typhimurium DT49 in Europe Ireland: From 2001-2004: 5 isolates all human. Not travel associated Enter-net data: Austria: From 2003-2004: 2 probable DT49. Travel to Turkey? Finland: 2003: One isolate DT49. Travel to Mexico Denmark: From 2000-2004 no human cases. 1998-1999 4 DT49 in pigs England and Wales: From 1984-1988 DT49 was most common phage type of S. Typhimurium Large hospital outbreak, House of Lords outbreak

12. Molecular Analysis – PFGE S. Typhimurium DT49 outbreak Isolates indistinguishable from each other and also from isolates from previous years XbaI restriction. S. Braenderup control

13. Molecular Analysis - Plasmids marker 2-16kb * Extra Plasmid band 60kb marker 90kb marker Serotype specific plasmid

14. Discussion First outbreak of DT49 >2 people reported in Ireland Prompt Intervention of Public Health Epidemiological investigation showed that foods containing liquid egg were strongly associated with symptoms Cross contamination ? Role of Salmonella Reference Laboratory Enter-net collaboration

15. Acknowledgements Enter-net National Disease Surveillance Center (NDSC) Food Safety Authority of Ireland (FSAI) Area Medical officers Environmental Health officers Infection control nurses Surveillance scientists NSRL Website address: http://www.nuigalway.ie/salmonella_lab/ From Midland Health Board Western Health Board Eastern Regional Health board