A regional outbreak of S. Enteritidis phage type 5, traced back to the flocks of an egg producer, Austria

Abstract

In the spring and summer of 2002, the Nationale Referenzzentrale für Salmonellen (National Reference Centre for Salmonella - NRCS) in Austria noticed a cluster of human Salmonella enterica subsp. enterica ser. Enteritidis phage type 5 (S. Enteritidis PT5) infections in two neighbouring districts of Austria. Another small outbreak of S. Enteritidis PT5 infections that occurred in the same region in 1999 had been traced back to the flocks of a local egg producer (approximately 6 000 hens). Attention was therefore again directed at this farm. The results of voluntary bacteriological examinations from the farm and further epidemiological investigations identified the same egg producer as the source of the second outbreak. The 70 human isolates of S. Enteritidis PT5 ascertained in 2002 represented a minority of all infections. It is realistic to estimate that several hundred infections occurred in the course of the 2002 outbreak. The farmer had not vaccinated new flocks against Salmonella since August 2001. It is likely that the change in vaccination policy resulted in the reappearance of the S. Enteritidis PT5 infections. By the end of September 2002 the farmer had stopped selling untreated table eggs. In October 2002 only one isolate of S. Enteritidis PT5 was ascertained in the region.

Antimicrobial resistance of Salmonella spp. and Escherichia coli isolated from table eggs

“…It has been demonstrated that there are geographical distributions of S. Enteritidis phage types and there is also evidence of changing phage types of the pathogen even within countries and regions (Mare et al, 2000;Nygard et al, 2004). It is also known that various phage types of S. Enteritidis isolates from table eggs have been implicated in human epidemics of salmonellosis (Berghold et al, 2003;Kowalczyk-Pecka et al, 2003;Majtanova, 1997;Simango & Mbewe, 2000). The role of PT1 compared with that of PT4 in egg-borne gastroenteritis in Trinidad therefore needs further investigation to ascertain whether there is a change in pattern.…”

“…Salmonella Enteritidis phage type 4 (PT4) has been most frequently associated with egg-borne salmonellosis in many epidemics worldwide although other phage types have also been implicated (Berghold, Kornschober, & Weber, 2003;IndarHarrinauth et al, 2001;Kowalczyk-Pecka, Wernicki, & Puchalski, 2003;Mare, Van der Walt, & Dicks, 2000;Nygard et al, 2004). Pulse-Weld gel electrophoresis (PFGE) has been used to determine the relatedness of S. Enteritidis isolates (Cardinale et al, 2005).…”

Prevalence of Salmonella species from poultry eggs of local stores in Duhok

“…Several Salmonellosis outbreaks have been reported where eggs were the source of human infection in particular, undercooked or raw eggs are at high risk for humans. [4][5][6] Salmonellae reside in the intestinal tract and are shed in the faeces of infected animals and humans as well. Many foods, particularly those of animal origin and those 1 Department of Medical Laboratory Technology, Zakho Technical Institute, Duhok Polytechnic University, Duhok, Iraq 2 Department of Biology, Faculty of Science, University of Zakho, Duhok, Iraq subject to sewage pollution, have been identified as vehicles for transmitting these pathogens.…”

Salmonellosis in Austria: situation and trends

“…In the course of an outbreak the NRCS is able to support the outbreak investigation team with additional information by using molecular discrimination techniques such as PFGE or MLVA. Based on the close cooperation of public health authorities, veterinary disease control officers, and food inspectors with the Competence Center for Infectious Diseases Epidemiology and the NRCS several outbreaks have been traced back to their sources thereby preventing further infections [24][25][26][27][28]. These measures -the introduction of the vaccination of laying hens and broilers and intensified outbreak investigation efforts -have led to a remarkable decrease of human salmonella infections in Austria.…”