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To gain information on laboratory hygiene in contained-use laboratories, a method was developed to study the presence of microorganisms on laboratory equipment. Focusing detection on genetically modified organisms (GMOs) containing the universal M13 primer binding sites enabled the detection of a broad range of GMOs using a single PCR. Swabbing surfaces in three different contained-use laboratories led to detection of M13-containing PCR products in 26 out of 34 swabs. Most sequences (up to five per sample) were detected in swabs from the centrifuge and sink, followed by swabs taken from the bin and incubator (up to four sequences per sample). The obtained sequences varied in length from 171 nucleotides (nt) to 878 nt. In most cases, sequences were only partially similar to sequences published in GenBank. The lengths of the regions with high similarity varied from 94 nt to 795 nt, and these similarities ranged from 81% to 100%. Similarities with more than one sequence were commonly found, complicating the identification of detected sequences. Nonetheless, 84% of the detected sequences were actually handled in the laboratory at the time of sampling. This demonstrates that the method may be used as a quality control tool to assess the efficacy of decontamination and cleaning of commonly used surfaces, such as laboratory benches, freezer doors, and centrifuge rotors, without prior knowledge of the identity or characteristics of the GMOs. [ABSTRACT FROM AUTHOR]

Non-travel-related hepatitis E virus (HEV) genotype 3 infections in persons in the Netherlands may have a zoonotic, foodborne, or water-borne origin. Possible reservoirs for HEV transmission by water, food, and animals were studied. HEV genotype 3/open reading frame 2 sequences were detected in 53% of pig farms, 4% of wild boar feces, and 17% of surface water samples. HEV sequences grouped within 4 genotype 3 clusters, of which 1 is so far unique to the Netherlands. The 2 largest clusters contained 35% and 43% of the animal and environmental sequences and 75% and 6%, respectively, of human HEV sequences obtained from a study on Dutch hepatitis E patients. This finding suggests that infection risk may be also dependent on transmission routes other than the ones currently studied. Besides the route of exposure, virus characteristics may be an important determinant for HEV disease in humans. [ABSTRACT FROM AUTHOR]

Consumption of virus-contaminated shellfish has caused numerous outbreaks of gastroenteritis and hepatitis worldwide. In The Netherlands, oysters are cultured and imported both for consumption and export; therefore, the presence of noroviruses, rotaviruses, astroviruses, hepatitis A viruses, and enteroviruses was determined in 64 commercial and noncommercial oyster samples. Oysters were collected monthly for 13 months from four different harvesting areas in the Oosterschelde Delta. Oyster samples were classified by determining Escherichia coli levels according to the standards set by the Councils Directive (91/492/EEC). Two of 36 commercial and 2 of 28 noncommercial oyster samples were B-classified and therefore not ready for consumption. All other oyster samples were A-classified. For the detection of viral RNA, 150 mg of hepatopancreatic tissue was subjected to the Qiagen RNeasy Mini Kit, followed by reverse transcriptase (RT)-PCR and Southern blot hybridization. Enterovirus RNA was detected in 14 of 64 oyster samples, of which 4 were from noncommercial oyster harvesting areas and 10 were from commercial harvesting areas. None of the other human pathogenic viruses were detected. The levels of somatic coliphages and F-specific phages were also determined in all 64 oyster samples, with some samples containing high phage levels (»50 PFU/g of hepatopancreatic tissue), but with most samples containing low phage levels («50 PFU/g of hepatopancreatic tissue). However, independent of these high or low phage levels, enterovirus RNA could he detected. Thus, commercial oysters can be contaminated with pathogenic viruses, and monitoring only fecal indicators might not sufficiently protect human health. [ABSTRACT FROM AUTHOR]