Shiga toxin-producing Escherichia coli (STEC) O157 outbreak, The Netherlands, September - October 2005.

In September 2005, the first national food-related outbreak of Shiga toxin (Stx)-producing Escherichia coli (STEC) O157 was investigated in the Netherlands. A total of 21 laboratory-confirmed cases (including one secondary case), and another 11 probable cases (two primary and nine secondary cases) were reported in patients who became ill between 11 September and 10 October 2005. Preliminary investigation suggested consumption of a raw beef product, steak tartare (in the Netherlands also known as 'filet americain'), and contact with other symptomatic persons as possible risk factors. A subsequent case-control study supported the hypothesis that steak tartare was the source of the outbreak (matched odds ratio (OR) 272, 95% confidence interval (CI) 3 - 23211). Consumption of ready-to-eat vegetables was also associated with STEC O157 infection (matched OR 24, 95% CI 1.1 - 528), but was considered a less likely source, as only 40% of the cases were exposed. Samples of steak tartare collected from one chain of supermarkets where it is likely that most patients (67%) bought steak tartare, all tested negative for STEC O157. However, sampling was done three days after the date of symptom onset of the last reported case. Since 88% of the cases became ill within a two week period, point source contamination may explain these negative results. It is concluded that steak tartare was the most likely cause of the first national food-related outbreak of STEC O157 in the Netherlands

Microbiome to Brain:Unravelling the Multidirectional Axes of Communication

The gut microbiome plays a crucial role in host physiology. Disruption of its community structure and function can have wide-ranging effects making it critical to understand exactly how the interactive dialogue between the host and its microbiota is regulated to maintain homeostasis. An array of multidirectional signalling molecules is clearly involved in the host-microbiome communication. This interactive signalling not only impacts the gastrointestinal tract, where the majority of microbiota resides, but also extends to affect other host systems including the brain and liver as well as the microbiome itself. Understanding the mechanistic principles of this inter-kingdom signalling is fundamental to unravelling how our supraorganism function to maintain wellbeing, subsequently opening up new avenues for microbiome manipulation to favour desirable mental health outcome

Risk factors for Salmonella Enteritidis and Typhimurium (DT104 and non-DT104) infections in The Netherlands: predominant roles for raw eggs in Enteritidis and sandboxes in Typhimurium infections

Since 1996 Salmonella Typhimurium DT104 salmonellosis has increased in The Netherlands. This prompted a case-control study of risk factors for salmonellosis to inform transmission routes for this phage type. Cases were laboratory-confirmed patients with a Salmonella infection and controls were selected from population registries by frequency matching for age, sex, degree of urbanization and season. Cases and controls received a questionnaire on risk factors. Of the 1171 cases, 573 (49%) responded: 245 S. Enteritidis and 232 S. Typhimurium cases (both DT104 and non-DT104), of which 58 were DT104. Of the 10 250 controls, 3409 (33%) responded. Use of H2 antagonists [odds ratio (OR) 4·4, 95% CI 1·6–12·2] and proton pump inhibitors (OR 4·2, 95% CI 2·2–7·9), consumption of raw eggs (OR 3·1, 95% CI 1·3–7·4) and products containing raw eggs (OR 1·8, 95% CI 1·1–3·0) were associated with endemic S. Enteritidis infection. Risk factors for endemic S. Typhimurium infection were use of proton pump inhibitors (OR 8·3, 95% CI 4·3–15·9), occupational exposure to raw meat (OR 3·0, 95% CI 1·1–7·9), playing in a sandbox (for children aged 4–12 years) (OR 2·4, 95% CI 1·6–3·7), consumption of undercooked meat (OR 2·2, 95% CI 1·1–4·1) and use of antibiotics (OR 1·9, 95% CI 1·0–3·4). Use of proton pump inhibitors (OR 11·2, 95% CI 3·9–31·9) and playing in a sandbox (OR 4·4, 95% CI 1·8–10·7) were the only risk factors for S. Typhimurium DT104 salmonellosis. This study confirms known risk factors for salmonellosis. However, playing in a sandbox was a predominant new risk factor for S. Typhimurium salmonellosis in children [population attributable risk (PAR) 14%], and especially for S. Typhimurium DT104 (PAR 32%)

Molecular Characterizations of Human and Animal Group A Rotaviruses in The Netherlands

To gain more insight into interspecies transmission of rotavirus group A, human and animal fecal samples were collected between 1997 and 2001 in The Netherlands. A total of 110 human stool samples were successfully P and G genotyped by reverse transcriptase PCR. All strains belonged to the main human rotavirus genotypes G1 to G4, G9, [P4], [P6], [P8], and [P9]. [P8]G1 was predominant, and 5.5% belonged to the G9 genotype. Eleven percent of all P[8] genotypes could be genotyped only by a recently published modified primer. Rotavirus-positive fecal samples from 28 calf herds were genotyped by DNA sequencing. Genotypes G6 and G10 predominated; G6 and G10 were detected in 22 (78.6%) and 16 (57.1%) of the rotavirus-positive calf herds, respectively. In 12 (42.9%) calf herds, we found mixed infections. Genotype G8 was not found. Genotype G6 bovine rotaviruses were divided into three clusters: UK-like, VMRI-29-like, and Hun4-like. DNA sequencing of a part of the VP7 gene was shown to be useful as a quick determination of uncommon or novel strains of which the genotyping cannot be done by genotyping PCR. Of equine strains, both VP4 and VP7 genes could be used for genotyping: two [P12]G3 and four [P12]G14 equine rotaviruses were determined. We did not find indications for rotavirus interspecies transmissions, although the recently published human G6-Hun4 is genetically related to our G6 bovine isolates. All bovine, porcine, and equine rotaviruses were within genotypes previously reported for these animal species

Gastroenteritis associated with accidental contamination of drinking water with partially treated water

Due to human error, drinking water supplied to a new housing estate in The Netherlands was contaminated with grey water. The cohort of 921 accidentally exposed households (area A) had a higher attack rate for diarrhoea (54·1%) than a non-exposed cohort of 1529 households from an adjacent area (B) (24%) (RR 2·3, 95% CI 1·9–2·7). Household water score showed a dose-response with illness, in both areas A and B. For each 1000 inhabitants, 19·8 cases in area A, 7·0 cases in control area B (RRAB 2·2, 95% CI 1·3–3·8) and 3·3 cases in a more distant control area C (RRAC 4·6, 95% CI 2·7–8·0) were diagnosed with gastroenteritis by their general practitioner. A gastroenteritis outbreak associated with consumption of contaminated drinking water was observed in the exposed area. The use of grey water was banned in 2003, with the exception of rainwater use for flushing toilets. The risk of rainwater use is currently being investigated

Escherichia coli O157 infection associated with a petting zoo.

A young child was admitted to hospital with haemolytic-uraemic syndrome caused by infection with a Shiga toxin 2-producing strain of Escherichia coli (STEC) O157. Five days before he became ill, the child had visited a small petting zoo. STEC O157 strains were isolated from faecal samples from goats and sheep housed on the farm. The human and the animal isolates were indistinguishable by molecular subtyping. The petting zoo voluntarily closed temporarily to prevent further cases of infection. Two out of 11 other, randomly selected petting zoos (including one deer park) visited subsequently, tested positive. Furthermore, during the study period there was one more notification of STEC O157 infection possibly linked with a farm visit. Although STEC O157 was indeed found in the petting zoo associated with this patient, transmission through animal contact could not be confirmed because the human isolate was not available for subtyping. The case study and the results of the other on-farm investigations highlight the risk of acquiring severe zoonotic infections during visits to petting zoos