The role of domestic reservoirs in domestically acquired infections in Norway: epidemiology of salmonellosis, 2000-2015, and results of a national prospective case-control study, 2010-2012.

In Norway, incidence of sporadic domestically acquired salmonellosis is low, and most frequently due to Salmonalla Typhimurium. We investigated the risk factors for sporadic Salmonella infections in Norway to improve control and prevention measures. Surveillance data for all Salmonella infections from 2000 to 2015 were analysed for seasonality and proportion associated with domestic reservoirs, hedgehogs and wild birds.

Risk Factors for Sporadic Domestically Acquired Campylobacter Infections in Norway 2010-2011: A National Prospective Case-Control Study.

Background: Campylobacteriosis is the most frequently reported food- and waterborne infection in Norway. We investigated the risk factors for sporadic Campylobacter infections in Norway in order to identify areas where control and prevention measures could be improved.

Methods: A national prospective case-control study of factors associated with Campylobacter infection was conducted from July 2010 to September 2011.

Shiga toxin-producing escherichia coli infections in Norway, 1992-2012: characterization of isolates and identification of risk factors for haemolytic uremic syndrome.

Background: Shiga toxin-producing E. coli (STEC) infection is associated with haemolytic uremic syndrome (HUS). Therefore Norway has implemented strict guidelines for prevention and control of STEC infection.

The national web-based outbreak rapid alert system in Norway: eight years of experience, 2006-2013.

In 2005, the Norwegian Institute of Public Health established a web-based outbreak rapid alert system called Vesuv. The system is used for mandatory outbreak alerts from municipal medical officers, healthcare institutions, and food safety authorities. As of 2013, 1426 outbreaks have been reported, involving 32913 cases.

Two outbreaks of diarrhoea in nurseries in Norway after farm visits, April to May 2009.

During a 2009 nationwide outbreak of sorbitolfermenting Escherichia coli O157 in Norway, the Norwegian Institute of Public Health was notified of diarrhoea outbreaks in two nurseries. A link to the nationwide outbreak was suspected and investigated, including retrospective cohort studies. Both nurseries had recently visited farms.

Norwegian sheep are an important reservoir for human-pathogenic Escherichia coli O26:H11.

A previous national survey of Escherichia coli in Norwegian sheep detected eae-positive (eae(+)) E. coli O26:H11 isolates in 16.3% (80/491) of the flocks.

Identification of the anti-terminator qO111:H)- gene in Norwegian sorbitol-fermenting Escherichia coli O157:NM.

Sorbitol-fermenting Escherichia coli O157:NM (SF O157) is an emerging pathogen suggested to be more virulent than nonsorbitol-fermenting Escherichia coli O157:H7 (NSF O157). Important virulence factors are the Shiga toxins (stx), encoded by stx1 and/or stx2 located within prophages integrated in the bacterial genome. The stx genes are expressed from p(R) (') as a late protein, and anti-terminator activity from the Q protein is necessary for read through of the late terminator t(R) (') and activation of p(R) (') .

Detection of virulent Escherichia coli O157 strains using multiplex PCR and single base sequencing for SNP characterization.

Aims: To compare 167 Norwegian human and nonhuman Escherichia coli O157:H7/NM (nonmotile) isolates with respect to an A/T single nucleotide polymorphism (SNP) in the tir gene and to detect specific SNPs that differentiate STEC O157 into distinct virulence clades (1-3 and 8).

Methods And Results: We developed a multiplex PCR followed by single base sequencing for detection of the SNPs, and examined the association among SNP genotype, virulence profile (stx and eae status), multilocus variable number of tandem repeats analysis (MLVA) profile and clinical outcome. We found an over-representation of the T allele among human strains compared to nonhuman strains, including 5/6 haemolytic-uraemic syndrome cases.

Shigella sonnei infections in Norway associated with sugar peas, May-June 2009.

In May 2009, the Norwegian Institute of Public Health (NIPH) identified a possible outbreak of Shigella sonnei infection involving four cases. Additionally, five suspected cases in two separate households were reported. Inspectors from the Norwegian Food Safety Authority (NFSA) visited the two households and found an unopened package of sugar peas imported from Kenya in one of the households.

An outbreak of Salmonella Typhimurium infections in Denmark, Norway and Sweden, 2008.

In November-December 2008, Norway and Denmark independently identified outbreaks of Salmonella Typhimurium infections characterised in the multiple-locus variable number of tandem repeats analysis (MLVA) by a distinct profile. Outbreak investigations were initiated independently in the two countries. In Denmark, a total of 37 cases were identified, and multiple findings of the outbreak strain in pork and pigs within the same supply chain led to the identification of pork in various forms as the source.

Outbreak of haemolytic uraemic syndrome in Norway caused by stx2-positive Escherichia coli O103:H25 traced to cured mutton sausages.

Background: On 20-21 February 2006, six cases of diarrhoea-associated haemolytic uraemic syndrome (HUS) were reported by paediatricians to the Norwegian Institute of Public Health. We initiated an investigation to identify the etiologic agent and determine the source of the outbreak in order to implement control measures.

Methods: A case was defined as a child with diarrhoea-associated HUS or any person with an infection with the outbreak strain of E.

Outbreak of Salmonella Thompson infections linked to imported rucola lettuce.

On November 15, 2004, a cluster of three cases of Salmonella Thompson infection was registered by the Norwegian reference laboratory. In the following days further cases occurred, prompting a case-control study among the first 13 cases and 26 matched controls. By December 31, 21 cases had been reported, with the first onset on October 24.

Outbreak of Yersinia enterocolitica serogroup O:9 infection and processed pork, Norway.

An outbreak involving 11 persons infected with Yersinia enterocolitica O:9 was investigated in Norway in February 2006. A case-control study and microbiologic investigation indicated a ready-to-eat pork product as the probable source. Appropriate control measures are needed to address consumer risk associated with this product.

Harmonization of the multiple-locus variable-number tandem repeat analysis method between Denmark and Norway for typing Salmonella Typhimurium isolates and closer examination of the VNTR loci.

Aims: Harmonization and evaluation of the multiple-locus variable-number tandem repeat analysis (MLVA) method for sub-typing Salmonella enterica ssp. enterica serovar Typhimurium (Salm. Typhimurium) in Denmark and Norway, and analysis of the typing data.

Study of polymorphic variable-number of tandem repeats loci in the ECOR collection and in a set of pathogenic Escherichia coli and Shigella isolates for use in a genotyping assay.

The Escherichia coli (E. coli) reference collection, ECOR, consists of 72 strains that are representative of the genotypic diversity, as indexed by multilocus enzyme electrophoresis (MLEE), in the species as a whole. MLEE revealed 4 main phylogenetic groups designated A, B1, B2 and D.

Octaplex PCR and fluorescence-based capillary electrophoresis for identification of human diarrheagenic Escherichia coli and Shigella spp.

A multiplex PCR assay, amplifying seven specific virulence genes and one internal control gene in a single reaction, was developed to identify the five main pathotypes of diarrheagenic Escherichia coli and Shigella spp. The virulence genes selected for each category were Stx1, Stx2, and eaeA for enterohemorrhagic E. coli (EHEC), eaeA for enteropathogenic E.

Intestinal carriage of Campylobacter jejuni and Campylobacter coli among cattle from south-western Norway and comparative genotyping of bovine and human isolates by amplified-fragment length polymorphism.

In a survey conducted in 1999-2001, the carriage of thermotolerant Campylobacters in cattle was investigated, and the genetic diversity of C. jejuni within one herd was examined and compared with human isolates. C.

Outbreak of Salmonella Livingstone infection in Norway and Sweden due to contaminated processed fish products.

In Europe, the number of reported sporadic human cases of Salmonella Livingstone infection is low, and outbreaks are rare. We report the largest S. Livingstone outbreak described in the literature having an identified source of infection.

Multiple-locus variable-number tandem-repeats analysis of Salmonella enterica subsp. enterica serovar Typhimurium using PCR multiplexing and multicolor capillary electrophoresis.

The multiple-locus variable-number tandem-repeats analysis (MLVA) method is currently being used as the primary typing tool for Salmonella enterica subsp. enterica serovar Typhimurium (S. Typhimurium) isolates in our laboratory.