H A Mather

Packed with Salmonella--investigation of an international outbreak of Salmonella Senftenberg infection linked to contamination of prepacked basil in 2007.

Salmonella Senftenberg is uncommon in the United Kingdom. In January-June 2007, the Health Protection Agency reported on 55 primary human cases of Salmonella Senftenberg in England and Wales. In May 2007, fresh basil sold in the United Kingdom was found to be contaminated with Salmonella Senftenberg. We launched an investigation to elucidate the cause of this outbreak. Isolates were examined using plasmid profiling and pulsed-field gel electrophoresis, and the outbreak strain (SSFTXB.0014) was identified. We enquired via Enter-net whether other countries had isolated the outbreak strain, analyzed samples of fresh herbs from U.K. retailers, and interviewed patients on food history. Thirty-two patient-cases were referred to this outbreak in England and Wales. Onsets of illness occurred between 5 March and 6 June 2007. Fifty-six percent of patient-cases were females and 90% adults (>20 years old); three were admitted to hospital as a result of Salmonella infection. Scotland, Denmark, the Netherlands, and the United States reported on 19 cases of Salmonella Senftenberg infection presenting with the outbreak strain since January 2007. Eight samples of prepacked fresh basil imported from Israel tested positive with the same strain. A minority of patients could recall the consumption of basil before illness, and some reported consumption of products where basil was a likely ingredient. Environmental investigations in Israel did not identify the contamination source. Microbiological evidence suggested an association between contamination of fresh basil and the cases of Salmonella Senftenberg infection, leading to withdrawal of basil from all potentially affected batches from the U.K. market.

Isolation of different serovars of Salmonella enterica from wild birds in Great Britain between 1995 and 2003

Postmortem examinations were carried out on the carcases of 779 wild birds. Salmonellosis was a common cause of death in greenfinches (Carduelis chloris), house sparrows (Passer domesticus) and chaffinches (Fringilla coelebs), and was also responsible for the deaths of other birds such as goldfinches (Carduelis carduelis), feral pigeons and different species of gulls. Most cases of salmonellosis in finches occurred between January and March, whereas salmonellosis in house sparrows tended to occur between October and March. Salmonella Typhimurium DT40 and DT56 (variant) predominated in finches and sparrows, DT41 and DT195 were the most common strains isolated from gulls, and DT2 and DT99 were recovered from feral pigeons. These ‘wild bird’ strains of Salmonella made up less than 0·5 per cent of the isolates of Salmonella recovered from cattle, sheep, pigs, chickens or turkeys in Great Britain over the same period, but they made up nearly 3 per cent of the isolates from more extensively reared avian livestock such as gamebirds, ducks and geese.

Salmonella enterica subspecies enterica serotype Typhimurium and Escherichia coli 086 in wild birds at two garden sites in south-west Scotland

Salmonella enterica subspecies enterica serotype Typhimurium and Escherichia coli 086:K61 :NM are two bacteria that can cause outbreaks of mortality in garden birds visiting bird tables and other feeding stations. Two sites in south-west Scotland were monitored for the two organisms for 12 months. At site A, large numbers of birds fed throughout the year, and at site B smaller numbers of birds fed only in the winter months. Samples of composite faeces were collected from the feeding stations and screened for the organisms, and any dead birds were also screened. S Typhimurium definitive type (DT) 56 (variant) was found to be endemic at site A, and was recovered from 48 per cent of samples of composite faeces collected from the bird table, from 42 per cent of composite faeces from underneath a hanging feeder, and from 33 per cent of composite faeces from below a roost used by house sparrows; the organism was also isolated from the carcases of six wild birds found dead at the site. In contrast, S Typhimurium (DT41) was recovered only once at site B, from 2 per cent of the composite faeces from below a hanging feeder, and no dead birds were recovered from the site. E coli 086 was not recovered from the faeces collected from either site, but was isolated from a bird that died from trauma at site A.

Isolation of avian strains of Salmonella enterica serovar Typhimurium from cats with enteric disease in the United Kingdom

AVIAN-ADAPTED strains of Salmonella enterica serovar Typhimurium have been detected in wild birds, particularly finches (family Fringillidae), in Europe, Scandinavia and North America ([Daoust and others 2000][1], [Tauni and Osterlund 2000][2], [Pennycott and others 2006][3]). In the uk, these

Salmonellosis in garden birds in Scotland, 1995 to 2008: geographic region, Salmonella enterica phage type and bird species

Salmonellosis was diagnosed in garden birds from 198 incidents in Scotland between September 1995 and August 2008. Salmonellosis was essentially a disease of finches in the north of Scotland, but in the south of Scotland it was also a problem in house sparrows. Almost all of the incidents were caused by Salmonella Typhimurium phage types 40 or 56/variant, but regional variation in phage types was observed. In the north of Scotland, one phage type (DT 40) predominated, but in the south of Scotland two phage types were commonly isolated (DTs 40 and 56/variant, with the latter the more common of the two phage types). This regional difference was statistically significant for salmonellosis in greenfinches, chaffinches and ‘other garden birds’, but not for house sparrows. Different temporal patterns for different species of bird and different phage types were also observed within regions. These findings suggest that the epidemiology of salmonellosis in garden birds varies depending on the phage type of Salmonella and the species of garden bird, with additional regional differences depending on the wild bird populations and the phage types of Salmonella in circulation. An awareness of these differences will help when formulating guidelines aimed at reducing the impact of salmonellosis in garden birds.

Serovars, bacteriophage types and antimicrobial sensitivities associated with salmonellosis in dogs in the UK (1954-2012).

Serovars and bacteriophage (phage) types were determined for 442 isolates of Salmonella enterica from dogs in the UK submitted to the Scottish Salmonella Reference Laboratory from 1954 to 2012. The most frequent serovars were Salmonella Typhimurium (196 isolates; 44.3 per cent), Dublin (40 isolates; 9.0 per cent), Enteritidis (28 isolates; 6.3 per cent), Montevideo (19 isolates; 4.3 per cent), Virchow (10 isolates; 2.3 per cent), Heidelberg (8 isolates; 1.8 per cent) and Derby (8 isolates; 1.8 per cent), along with 55 other recognised serovars among 127 other isolates, and six incompletely classified isolates. Serovars were frequently represented by strains commonly associated with poultry, cattle or pigs and their products. Among 196 Salmonella Typhimurium isolates from dogs, the most frequent phage types (definitive types) were the multiple antimicrobial-resistant strains DT104 (62 isolates), DT204c (18 isolates) and DT193 (8 isolates), along with antimicrobial sensitive wild finch strains DT40 (13 isolates) and DT56 variant (8 isolates). Eleven of 28 isolates of Salmonella Enteritidis were phage type 4. S enterica was frequently recovered from faecal or intestinal samples of dogs with diarrhoea, although many dogs had concurrent infection with other enteric pathogens. Salmonella Dublin was recovered from the brain and/or cerebrospinal fluid of two dogs with meningoencephalitis. Salmonella Kedougou was isolated from the joint fluid of a dog with septic arthritis. Salmonella Typhimurium and Salmonella Dublin were each recovered from the vaginas of bitches that had aborted. Isolates of Salmonella Enteritidis phage types 1, 4 and 8, Salmonella Typhimurium DT104, Salmonella Dublin and Salmonella Indiana were isolated from clinically healthy dogs in households where the same strains were recovered from human beings with diarrhoea. The pattern ampicillin-chloramphenicol-spectinomycin-streptomycin-sulfamethoxazole-tetracycline (ACSpSSuT) was the most frequent resistance phenotype and was observed in 44 (13.3 per cent) of 330 isolates. Dogs in the UK are exposed to a wide variety of serovars of S enterica, sometimes associated with clinical disease, and represent a zoonotic risk.

Further monitoring for Salmonella species and Escherichia coli O86 at a bird table in south-west Scotland

Pooled faeces collected from a garden bird table were screened for Salmonella species and Escherichia coli O86, two recognised causes of garden bird mortality. Dead birds found at the site were also screened for these organisms, and bird numbers and meteorological data were recorded. In the first year of the study, 48·5 per cent of the samples were positive for Salmonella Typhimurium DT56 (variant), decreasing to 38·9 per cent in the second year and 12·8 per cent in the third year. E coli O86 was not recovered from any of the 288 samples of pooled faeces tested. S Typhimurium DT56 (variant) was recovered from the carcases of eight birds found dead at the site, and E coli O86 was isolated from three carcases. The degree of contamination of the bird table with S Typhimurium DT56 (variant) was positively correlated with the number of house sparrows observed in the garden, but not with the number of blackbirds, chaffinches or greenfinches.