The characterization of Danish isolates of Salmonella enterica serovar Enteritidis by phage typing and plasmid profiling: 1980–1990

Abstract

Plasmid profiling, phage typing and antimicrobial resistance typing have been carried out on 736 isolates of Salmonella enterica serovar Enteritidis collected in Denmark during the period 1980 to 1990. Strains originated from cases of human salmonellosis, broiler poultry flocks, layer poultry flocks, quarantined imported poultry, environmental samples from hatchery units, and from bovines. Phage type (PT) 1 was found to be the most common type among isolates of poultry origin (57.6%) followed by PT4 (28.8%). Isolates belonging to PT8 were found exclusively in imported birds. Phage typing of a representative sample of human isolates revealed the predominance, as in most other Western European countries, of PT4 (61.8%). PTI, however, was found in 17.0% of human strains, a much higher incidence than expected. Antibiotic resistance was observed in 4 out of 107 human isolates (3.7%) and 2 out of 205 non‐human isolates (1%) tested.

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

“…Amongst S. Enteritidis isolates, the prevalence of multi-resistance was considerably low, 1.4%, a Wnding in agreement with report of Yang et al (2002) but considerably lower than that found by Dias de Oliveira, Siqueira Flores, Dos Santos, and Brandelli (2005). Similarly, the prevalence of resistance, as determined by resistance to one or more antimicrobial agents, although higher than reported for isolates from table eggs by Brown et al (1994) is signiWcantly lower than found in Brazil (Simango & Mbewe, 2000). It has been reported that inappropriate use of antimicrobial agents in livestock may result in the development of resistance amongst bacteria in these animals or their products (Washington, 1979;Waltner-Toews & McEwen, 1994).…”

“…A prevalence of 22.9% for resistance to antimicrobial agents detected amongst Salmonella isolates from eggs is considerably lower than the prevalence of 50% reported for Salmonella isolates recovered from livestock in Trinidad (Adesiyun, Kaminjolo, Loregnard, & Kitson-Piggott, 1993) and elsewhere (Brown, Baggesen, Hansen, Hansen, & Bisgaard, 1994;Hang'ombe et al, 1999;Poppe, 1994;Neu, Cherubin, Longo, Flouton, & Winter, 1975;Wray, Beedell, & McLaren, 1991). Amongst S. Enteritidis isolates, the prevalence of multi-resistance was considerably low, 1.4%, a Wnding in agreement with report of Yang et al (2002) but considerably lower than that found by Dias de Oliveira, Siqueira Flores, Dos Santos, and Brandelli (2005).…”

“…Enteritidis PT1 has however been recovered from cases of gastroenteritis in the country also emphasizing the clinical importance of this phage type (CAREC, 2002). Enteritidis PT1 has been implicated in egg-borne gastroenteritis in other countries (Brown et al, 1994;Kusunoki et al, 1999). 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).…”

Distribution of serotypes ofCampylobacter jejuniandC. colifrom Danish patients, poultry, cattle and swine

“…Serotyping or other typing methods are necessary epidemiological tools in studies of zoonotic bacteria. For example, combined serotyping and phage‐typing of salmonella isolates from humans, layer hens, broiler chickens, swine and cattle were used for assessing the significance of different production animals as a source of human infection [6, 7]. For campylobacters, comparison of types isolated from humans and potential sources of human infection has not been done over long time periods and to the same extent.…”

Genetic Diversity and Evolution of Salmonella enterica Serovar Enteritidis Strains with Different Phage Types

“…Phage typing has been found to be useful for the tracking of spatial and temporal distributions of S. Enteritidis. For example, phage type 8 (PT8), PT13a, and PT13 are taken to be most common in North America (5,6), while PT4 has been the dominant phage type in most countries of Western Europe (7)(8)(9). Additionally, PT14b represents a phage type that recently emerged in southern European countries in 2001 (10).…”