Epidemiology of Salmonella infections in sow herds in the Czech Republic

Salmonella prevalence was assessed in six herds of sows by serological ELISA test and faecal culture. Blood and faecal samples were collected, prior to weaning of piglets, from 45 sows housed in separated pens in each group of a herd. Increased levels of specific antibodies were found in all six herds. Serologically positive samples averaged 41 .85%. Faecal shedding of Salmonella from the carriers was found in four herds with the average of 7.8%. Salmonella prevalence, as assessed by serological testing and faecal culture, was 17.8% and 13.3% in herd I, 20.0% and 4.4% in herd II, 40.0% and 20.0% in herd Ill, 53.3% and 0% in herd IV, 86.7% and 8.9% in herd V, and 30.3% and 0% in herd VI. A total of 21 Salmonella spp. strains were isolated which were classified into the serotype Derby (n=17), London (n=2). Bredeney (n=1 ), and Gold coast (n=1 ). All isolates were sensitive to the antibiotics used. No correlation was found between Salmonella seroprevalence in ELISA test and positive faecal culture in the examined herds of sows. The result of faecal culture was negative in two sow herds with high seroprevalence. Serological ELISA test is an efficient diagnostic tool for Salmonella detection in suspected herds. The results of our study showed association between the incidence of S. Derby in sows and slaughtered fattening pigs originated from the same farrow-to-finish herds

Emergence of new Salmonella Enteritidis phage types in Europe? Surveillance of infections in returning travellers

BACKGROUND: Among human Salmonella Enteritidis infections, phage type 4 has been the dominant phage type in most countries in Western Europe during the last years. This is reflected in Salmonella infections among Swedish travellers returning from abroad. However, there are differences in phage type distribution between the countries, and this has also changed over time. METHODS: We used data from the Swedish infectious disease register and the national reference laboratory to describe phage type distribution of Salmonella Enteritidis infections in Swedish travellers from 1997 to 2002, and have compared this with national studies conducted in the countries visited. RESULTS: Infections among Swedish travellers correlate well with national studies conducted in the countries visited. In 2001 a change in phage type distribution in S. Enteritidis infections among Swedish travellers returning from some countries in southern Europe was observed, and a previously rare phage type (PT 14b) became one of the most commonly diagnosed that year, continuing into 2002 and 2003. CONCLUSIONS: Surveillance of infections among returning travellers can be helpful in detecting emerging infections and outbreaks in tourist destinations. The information needs to be communicated rapidly to all affected countries in order to expedite the implementation of appropriate investigations and preventive measures

Epidemiology of Salmonella infections in sow herds in the Czech Republic

Salmonella prevalence was assessed in six herds of sows by serological ELISA test and faecal culture. Blood and faecal samples were collected, prior to weaning of piglets, from 45 sows housed in separated pens in each group of a herd. Increased levels of specific antibodies were found in all six herds. Serologically positive samples averaged 41 .85%. Faecal shedding of Salmonella from the carriers was found in four herds with the average of 7.8%. Salmonella prevalence, as assessed by serological testing and faecal culture, was 17.8% and 13.3% in herd I, 20.0% and 4.4% in herd II, 40.0% and 20.0% in herd Ill, 53.3% and 0% in herd IV, 86.7% and 8.9% in herd V, and 30.3% and 0% in herd VI. A total of 21 Salmonella spp. strains were isolated which were classified into the serotype Derby (n=17), London (n=2). Bredeney (n=1 ), and Gold coast (n=1 ). All isolates were sensitive to the antibiotics used. No correlation was found between Salmonella seroprevalence in ELISA test and positive faecal culture in the examined herds of sows. The result of faecal culture was negative in two sow herds with high seroprevalence. Serological ELISA test is an efficient diagnostic tool for Salmonella detection in suspected herds. The results of our study showed association between the incidence of S. Derby in sows and slaughtered fattening pigs originated from the same farrow-to-finish herds.</p

An outbreak of human salmonellosis caused by ampicillin-resistant Salmonella enterica serovar Enteritidis PT13 in the Czech Republic

In summer 2004, an outbreak caused by Salmonella enterica serovar Enteritidis phage type 13 (S. Enteritidis PT13) was recorded in the Czech Republic. As well being a relatively rare phage type the strain was also ampicillin resistant. Outbreak (n=39) and pre-outbreak isolates (n=13) were characterized by pulsed-field gel electrophoresis (PFGE), β-lactamase gene polymerase chain reaction and plasmid profile. The majority of outbreak isolates (n=37) were identical in XbaI PFGE profile, and two other outbreak isolates each differed from this profile by one or two fragments respectively. The pre-outbreak isolates were uniform in PFGE profile but distinct from the outbreak strain. Ampicillin resistance was confirmed to be encoded by the blaTEM gene located on the TnA transposon. This gene was readily transferable to a S. Enteritidis recipient strain and was associated with the transfer of a 200-kb plasmid. Our results indicate that all S. Enteritidis PT13 tested from 2004 belonged to a single outbreak strain which prior to 2004 had not been recognized in the Czech Republic