Listeriosis associated with pre-prepared sandwich consumption in hospital in England, 2017.

A case of listeriosis occurred in a hospitalised patient in England in July 2017. Analysis by whole genome sequencing of the Listeria monocytogenes from the patient's blood culture was identified as clonal complex (CC) 121. This culture was indistinguishable to isolates from sandwiches, salads and the maufacturing environment of Company X which supplied these products widely to the National Health Service. Whilst an inpatient, the case was served sandwiches produced by this company on 12 occasions. No other cases infected by this type were detected in the UK between 2016 and 2020. Between 2016 and 2020, more than 3000 samples of food, food ingredients and environmental swabs from this company were tested. Listeria monocytogenes contamination rates declined after July 2017 from 31% to 0.3% for salads and 3% to 0% for sandwiches. A monophyletic group of 127 L. monocytogenes CC121 isolates was recovered during 2016-2019 and was used to estimate the time of the most recent common ancestor as 2014 (95% CI of between 2012 and 2016). These results represent persistent contamination of equipment, food contact surfaces and foods at a food manufacturer by a single L. monocytogenes strain. Colonisation and persistent contamination of food and production environments are risks for public health.

Electron Electric Dipole Moment Searches Using Clock Transitions in Ultracold Molecules.

Permanent electric dipole moments (EDMs) of fundamental particles such as the electron are signatures of parity and time-reversal violation occurring in physics beyond the standard model. EDM measurements probe new physics at energy scales well beyond the reach of present-day colliders. Recent advances in assembling molecules from ultracold atoms have opened up new opportunities for improving the reach of EDM experiments. However, the magnetic field sensitivity of such ultracold molecules means that new measurement techniques are needed before these opportunities can be fully exploited. We present a technique that takes advantage of magnetically insensitive hyperfine clock transitions in polar molecules, offering a way to improve both the precision and accuracy of EDM searches with ultracold assembled molecules.

Human foodborne listeriosis in England and Wales, 1981 to 2015.

Almost all cases of human listeriosis are foodborne, however the proportion where specific exposures are identified is small. Between 1981 and 2015, 5252 human listeriosis cases were reported in England and Wales. The purpose of this study was to summarise data where consumption of specific foods was identified with transmission and these comprised 11 sporadic cases and 17 outbreaks. There was a single outbreak in the community of 378 cases (7% of the total) which was associated with pâté consumption and 112 cases (2% of the total) attributed to specific foods in all the other incidents. The proportion of food-attributed cases increased during this study with improvements in typing methods for Listeria monocytogenes. Ten incidents (one sporadic case and nine outbreaks of 2-9 cases over 4 days to 32 months) occurred in hospitals: all were associated with the consumption of pre-prepared sandwiches. The 18 community incidents comprised eight outbreaks (seven of between 3 and 17 cases) and 10 sporadic cases: food of animal origin was implicated in 16 of the incidents (sliced or potted meats, pork pies, pâté, liver, chicken, crab-meat, butter and soft cheese) and food of non-animal origin in the remaining two (olives and vegetable rennet).

Can We Perform CT of the Appendix with Less Than 1 mSv? A De-escalating Dose-simulation Study.

OBJECTIVES: To systematically explore the lowest reasonably achievable radiation dose for appendiceal CT using an iterative reconstruction (IR) in young adults. METHODS: We prospectively included 30 patients who underwent 2.0-mSv CT for suspected appendicitis. From the helical projection data, 1.5-, 1.0- and 0.5-mSv CTs were generated using a low-dose simulation tool and the knowledge-based IR. We performed step-wise non-inferiority tests sequentially comparing 2.0-mSv CT with each of 1.5-, 1.0- and 0.5-mSv CT, with a predetermined non-inferiority margin of 0.06. The primary end point was the pooled area under the receiver-operating-characteristic curve (AUC) for three abdominal and three non-abdominal radiologists. RESULTS: For the abdominal radiologists, the non-inferiorities of 1.5-, 1.0- and 0.5-mSv CT to 2.0-mSv CT were sequentially accepted [pooled AUC difference: 2.0 vs. 0.5 mSv, 0.017 (95% CI: -0.016, 0.050)]. For the non-abdominal radiologists, the non-inferiorities of 1.5- and 1.0-mSv CT were accepted; however, the non-inferiority of 0.5-mSv CT could not be proved [pooled AUC difference: 2.0 vs. 1.0 mSv, -0.017 (-0.070, 0.035) and 2.0 vs. 0.5 mSv, 0.045 (-0.071, 0.161)]. CONCLUSION: The 1.0-mSv appendiceal CT was non-inferior to 2.0-mSv CT in terms of diagnostic performance for both abdominal and non-abdominal radiologists; 0.5-mSv appendiceal CT was non-inferior only for abdominal radiologists. KEY POINTS: • For both abdominal and non-abdominal radiologists, 1.0-mSv appendiceal CT could be feasible. • The 0.5-mSv CT was non-inferior to 2.0-mSv CT only for expert abdominal radiologists. • Reader experience is an important factor affecting diagnostic impairment by low-dose CT.

An assessment of the microbiological quality of liver-based pâté in England 2012-13: comparison of samples collected at retail and from catering businesses.

The purpose of this study was to investigate the microbiological quality of liver pâté. During 2012-13, a total of 870 samples, unrelated to the investigation of food-poisoning outbreaks, were collected either at retail (46%), catering (53%) or the point of manufacture (1%) and were tested using standard methods to detect Salmonella spp. or Campylobacter spp., and to enumerate for Listeria spp., including Listeria monocytogenes, Clostridium perfringens, coagulase-positive staphylococci including Staphylococcus aureus, Bacillus spp., including Bacillus cereus, Escherichia coli, Enterobacteriaceae, and aerobic colony counts (ACCs). Seventy-three percent of samples were of satisfactory microbiological quality, 18% were borderline and 9% unsatisfactory. Salmonella spp. or Campylobacter spp. was not recovered from any sample. The most common causes of unsatisfactory results were elevated ACCs (6% of the samples) and high Enterobacteriaceae counts (4% of samples). The remaining unsatisfactory results were due to elevated counts of: E. coli (three samples); B. cereus (one sample at 2·6 × 105 cfu/g); or L. monocytogenes (one sample at 2·9 × 103 cfu/g). Pâté from retail was less likely to be contaminated with L. monocytogenes than samples collected from catering and samples from supermarkets were of significantly better microbiological quality than those from catering establishments.

An assessment of the microbiological quality of lightly cooked food (including sous-vide) at the point of consumption in England.

This observational study aims to investigate the microbiological quality of commercially prepared lightly cooked foods with a major component of food of animal origin and collected as would be served to a consumer. A total of 356 samples were collected from catering (92%), retail (7%) or producers (1%) and all were independent of known incidents of foodborne illness. Using standard methods, all samples were tested for: the presence of Campylobacter spp. and Salmonella spp. and enumerated for levels of, Bacillus spp. including B. cereus, Clostridium perfringens, Listeria spp. including L. monocytogenes, Staphylococcus aureus, Escherichia coli, Enterobacteriacea and aerobic colony count (ACC). Results were interpreted as unsatisfactory, borderline or satisfactory according to the Health Protection Agency guidelines for assessing the microbiological safety of ready-to-eat foods placed on the market. Amongst all samples, 70% were classified as satisfactory, 18% were borderline and 12% were of unsatisfactory microbiological quality. Amongst the unsatisfactory samples, six (2%) were potentially injurious to health due to the presence of: Salmonella spp. (one duck breast); Campylobacter spp. (two duck breast and one chicken liver pâté); L. monocytogenes at 4·3 × 103 cfu (colony-forming units)/g (one duck confit with foie gras ballotin) and C. perfringens at 2·5 × 105 cfu/g (one chicken liver pâté). The remaining unsatisfactory samples were due to high levels of indicator E. coli, Enterobacteriaceae or ACC.

An epidemiological review of gastrointestinal outbreaks associated with Clostridium perfringens, North East of England, 2012-2014.

An anecdotal increase in C. perfringens outbreaks was observed in the North East of England during 2012-2014. We describe findings of investigations in order to further understanding of the epidemiology of these outbreaks and inform control measures. All culture-positive (>105 c.f.u./g) outbreaks reported to the North East Health Protection Team from 1 January 2012 to 31 December 2014 were included. Epidemiological (attack rate, symptom profile and positive associations with a suspected vehicle of infection), environmental (deficiencies in food preparation or hygiene practices and suspected vehicle of infection) and microbiological investigations are described. Forty-six outbreaks were included (83% reported from care homes). Enterotoxin (cpe) gene-bearer C. perfringens were detected by PCR in 20/46 (43%) and enterotoxin (by ELISA) and/or enterotoxigenic faecal/food isolates with indistinguishable molecular profiles in 12/46 (26%) outbreaks. Concerns about temperature control of foods were documented in 20/46 (43%) outbreaks. A suspected vehicle of infection was documented in 21/46 (46%) of outbreaks (meat-containing vehicle in 20/21). In 15/21 (71%) identification of the suspected vehicle was based on descriptive evidence alone, in 5/21 (24%) with supporting evidence from an epidemiological study and in 2/21 (10%) with supporting microbiological evidence. C. perfringens-associated illness is preventable and although identification of foodborne outbreaks is challenging, a risk mitigation approach should be taken, particularly in vulnerable populations such as care homes for the elderly.

Investigation of an outbreak of vomiting in nurseries in South East England, May 2012.

On 30 May 2012, Surrey and Sussex Health Protection Unit was called by five nurseries reporting children and staff with sudden onset vomiting approximately an hour after finishing their lunch that day. Over the following 24 h 50 further nurseries supplied by the same company reported cases of vomiting (182 children, 18 staff affected). Epidemiological investigations were undertaken in order to identify the cause of the outbreak and prevent further cases. Investigations demonstrated a nursery-level attack rate of 55 out of 87 nurseries (63·2%, 95% confidence interval 52·2-73·3). Microbiological tests confirmed the presence of Bacillus cereus in food and environmental samples from the catering company and one nursery. This was considered microbiologically and epidemiologically consistent with toxin from this bacterium causing the outbreak. Laboratory investigations showed that the conditions used by the caterer for soaking of pearl haricot beans (known as navy bean in the USA) used in one of the foods supplied to the nurseries prior to cooking, was likely to have provided sufficient growth and toxin production of B. cereus to cause illness. This large outbreak demonstrates the need for careful temperature control in food preparation.

Pregnancy-associated listeriosis in England and Wales.

Listeriosis is a rare but severe foodborne disease with low morbidity and high case-fatality rates. Pregnant women, unborn and newborn babies are among the high-risk groups for listeriosis. We examined listeriosis cases reported to the enhanced surveillance system in England and Wales from 1990 to 2010 to identify risk factors influencing outcome. Cases were defined as pregnancy-associated if Listeria monocytogenes was isolated from a pregnant woman or newborn infants aged <28 days. Of the 3088 cases reported, pregnancy-associated listeriosis accounted for 462 (15%) cases and 315 cases resulted in a live birth. Several factors were identified as affecting the severity and outcome of listeriosis in pregnancy in both mother and child including: presence or absence of maternal symptoms, gestational age at onset of symptoms, and clinical presentation in the infant (meningitis or septicaemia). Deprivation, ethnicity and molecular serotype had no effect on outcome.

Infant botulism due to C. butyricum type E toxin: a novel environmental association with pet terrapins.

We describe two cases of infant botulism due to Clostridium butyricum producing botulinum type E neurotoxin (BoNT/E) and a previously unreported environmental source. The infants presented at age 11 days with poor feeding and lethargy, hypotonia, dilated pupils and absent reflexes. Faecal samples were positive for C. butyricum BoNT/E. The infants recovered after treatment including botulism immune globulin intravenous (BIG-IV). C. butyricum BoNT/E was isolated from water from tanks housing pet 'yellow-bellied' terrapins (Trachemys scripta scripta): in case A the terrapins were in the infant's home; in case B a relative fed the terrapin prior to holding and feeding the infant when both visited another relative. C. butyricum isolates from the infants and the respective terrapin tank waters were indistinguishable by molecular typing. Review of a case of C. butyricum BoNT/E botulism in the UK found that there was a pet terrapin where the infant was living. It is concluded that the C. butyricum-producing BoNT type E in these cases of infant botulism most likely originated from pet terrapins. These findings reinforce public health advice that reptiles, including terrapins, are not suitable pets for children aged <5 years, and highlight the importance of hand washing after handling these pets.

Outbreak of encephalitic listeriosis in red-legged partridges (Alectoris rufa).

An outbreak of neurological disease was investigated in red-legged partridges between 8 and 28 days of age. Clinical signs included torticollis, head tilt and incoordination and over an initial eight day period approximately 30-40 fatalities occurred per day. No significant gross post mortem findings were detected. Histopathological examination of the brain and bacterial cultures followed by partial sequencing confirmed a diagnosis of encephalitis due to Listeria monocytogenes. Further isolates were obtained from follow-up carcasses, environmental samples and pooled tissue samples of newly imported day-old chicks prior to placement on farm. These isolates had the same antibiotic resistance pattern as the isolate of the initial post mortem submission and belonged to the same fluorescent amplified fragment length polymorphism (fAFLP) subtype. This suggested that the isolates were very closely related or identical and that the pathogen had entered the farm with the imported day-old chicks, resulting in disease manifestation in partridges between 8 and 28 days of age. Reports of outbreaks of encephalitic listeriosis in avian species are rare and this is to the best of our knowledge the first reported outbreak in red-legged partridges.

Identification of six Listeria species by real-time PCR assay.

UNLABELLED: The Listeria genus comprises 10 recognized species. Listeria monocytogenes causes listeriosis in humans and other animals primarily via contaminated food or animal feed. Listeria ivanovii causes listeriosis in animals and on rare occasions in humans. The identification of nonpathogenic species of Listeria in foods indicates that conditions exist that support the growth of pathogenic strains and is used to facilitate the implementation of control and prevention measures. This study shows the development and evaluation of a 5'exonuclease real-time PCR assay for the rapid identification of Listeria seeligeri, Listeria welshimeri, L. monocytogenes, L. ivanovii, Listeria grayi and Listeria innocua. The assay consists of two triplexes that were evaluated using 53 cultures of Gram-positive bacteria, including 49 Listeria spp. from human, animal, food or food-processing environments. The assay was rapid, specific and reproducible and could identify each of the six species from a mixture of strains. The developed assay proved to be a powerful means of rapidly identifying Listeria species and could be usefully implemented in busy specialist reference laboratories. SIGNIFICANCE AND IMPACT OF THE STUDY: The identification of species of Listeria from foods is important to monitor pathogenic strains and facilitates the implementation of control measures. This study shows the development and evaluation of a 5'exonuclease real-time PCR assay for the rapid identification of L. seeligeri, L. welshimeri, L. monocytogenes and L. ivanovii, L. grayi, L. innocua. The developed assay proved to be specific, rapid and reproducible and therefore could be implemented in busy specialist reference laboratories.

Focused Exome Sequencing Gives a High Diagnostic Yield in the Indian Subcontinent.

The genetically isolated yet heterogeneous and highly consanguineous Indian population has shown a higher prevalence of rare genetic disorders. However, there is a significant socioeconomic burden for genetic testing to be accessible to the general population. In the current study, we analyzed next-generation sequencing data generated through focused exome sequencing from individuals with different phenotypic manifestations referred for genetic testing to achieve a molecular diagnosis. Pathogenic or likely pathogenic variants are reported in 280 of 833 cases with a diagnostic yield of 33.6%. Homozygous sequence and copy number variants were found as positive diagnostic findings in 131 cases (15.7%) because of the high consanguinity in the Indian population. No relevant findings related to reported phenotype were identified in 6.2% of the cases. Patients referred for testing due to metabolic disorder and neuromuscular disorder had higher diagnostic yields. Carrier testing of asymptomatic individuals with a family history of the disease, through focused exome sequencing, achieved positive diagnosis in 54 of 118 cases tested. Copy number variants were also found in trans with single-nucleotide variants and mitochondrial variants in a few of the cases. The diagnostic yield and the findings from this study signify that a focused exome test is a good lower-cost alternative for whole-exome and whole-genome sequencing and as a first-tier approach to genetic testing.

Microbiological Quality of Ready-to-Eat Salad Products Collected from Retail and Catering Settings in England during 2020 to 2021.

ABSTRACT: Salad and other fresh produce were collected in England from retail and catering businesses during 2020 to 2021 and were tested for Salmonella, Shiga toxin-producing Escherichia coli (STEC), Listeria, Bacillus cereus, and E. coli. Of the 604 samples collected, 57% were from retail settings and 43% were from catering settings; 61% were either salad leaves or salad leaves mixed with other products. Equal numbers of samples were prepacked or loose, and 50% were refrigerated at the time of sampling. Combining results for all microbiological parameters, 84% were interpreted as satisfactory, 12% were interpreted as borderline, and 4% were interpreted as unsatisfactory. One sample (prepacked leaves, cucumber, and tomato from a caterer) was categorized as unacceptable and potentially injurious because of detection of STEC O76; no STEC from human infections in the United Kingdom matched this isolate. No Salmonella enterica was detected, but Listeria monocytogenes was recovered from 11 samples: 1 at 20 CFU/g and the remainder at <20 CFU/g. B. cereus was detected at borderline levels (103 to ≤105 CFU/g) in 9% of samples and at an unsatisfactory level (>105 CFU/g) in one sample. E. coli was detected in 3% of samples at borderline levels (20 to ≤102 CFU/g) and in 4% at unsatisfactory levels (>102 CFU/g). There was a significant association between detection of L. monocytogenes and borderline or unsatisfactory levels of E. coli. There were no specific risk profiles associated with products with the higher levels of B. cereus, STEC, or Listeria, but elevated levels of E. coli were predominantly confined to loose products from the United Kingdom collected from caterers in summer or autumn 2021 and may have resulted from relaxation of COVID-19 restrictions. Among the L. monocytogenes isolates, only one matched those from human cases and was recovered from a prepacked mixed salad from a catering business in 2021. This isolate was the same strain as that responsible for a multicountry outbreak (2015 to 2018) associated with Hungarian-produced frozen sweet corn; no link to the outbreak food chain was established.

A cryogenic beam of refractory, chemically reactive molecules with expansion cooling.

Cryogenically cooled buffer gas beam sources of the molecule thorium monoxide (ThO) are optimized and characterized. Both helium and neon buffer gas sources are shown to produce ThO beams with high flux, low divergence, low forward velocity, and cold internal temperature for a variety of stagnation densities and nozzle diameters. The beam operates with a buffer gas stagnation density of ∼10(15)-10(16) cm(-3) (Reynolds number ∼1-100), resulting in expansion cooling of the internal temperature of the ThO to as low as 2 K. For the neon (helium) based source, this represents cooling by a factor of about 10 (2) from the initial nozzle temperature of about 20 K (4 K). These sources deliver ∼10(11) ThO molecules in a single quantum state within a 1-3 ms long pulse at 10 Hz repetition rate. Under conditions optimized for a future precision spectroscopy application [A. C. Vutha et al., J. Phys. B: At., Mol. Opt. Phys., 2010, 43, 074007], the neon-based beam has the following characteristics: forward velocity of 170 m s(-1), internal temperature of 3.4 K, and brightness of 3 × 10(11) ground state molecules per steradian per pulse. Compared to typical supersonic sources, the relatively low stagnation density of this source and the fact that the cooling mechanism relies only on collisions with an inert buffer gas make it widely applicable to many atomic and molecular species, including those which are chemically reactive, such as ThO.

Listeria monocytogenes in Cooked Chicken: Detection of an Outbreak in the United Kingdom (2016 to 2017) and Analysis of L. monocytogenes from Unrelated Monitoring of Foods (2013 to 2017).

ABSTRACT: In England and Wales, Public Health England applies whole genome sequencing to cultures of Listeria monocytogenes recovered from human cases of listeriosis, foods, and food production environments. Following the routine inspection of a small retailer in February and March 2016, two unopened packs of cooked chicken produced by the same manufacturer were found to be contaminated with L. monocytogenes at levels of 340 and 20 CFU/g. A public recall of this product was issued in March 2016. Early in 2017, a less than five single-nucleotide polymorphism single-linkage cluster was detected between the L. monocytogenes isolates from the two cooked chicken products and cultures from five cases of human listeriosis in England and Scotland with onsets of illness between March 2016 and February 2017. Epidemiological data provided further supportive evidence that this cluster was an outbreak linked to a manufacturer of cooked chicken whose products were supplied to the small retailer that initiated the outbreak investigation. Unrelated to this outbreak, 34 L. monocytogenes isolates recovered from routine food monitoring of 2,007 samples of cooked chicken during 2013 to 2017 were analyzed by whole genome sequencing. Previously undetected fewer than five single-nucleotide polymorphism single-linkage clusters were identified between cultures from cooked chicken and with those from two clusters and two sporadic cases of human listeriosis that were consistent with foodborne transmission. This analysis identified linkage of L. monocytogenes clusters within specific food chains more readily than traditional manual tracing. Linking of data associated with L. monocytogenes cultures from cases of listeriosis with those from unrelated food testing is a unique source of information for communicable disease risk assessment, epidemiological studies, and disease prevention and control. This report provides further evidence that should act as a reminder of the association between cooked chicken consumption and human listeriosis.

Vibration Versus Ice to Reduce Cosmetic Botulinum Toxin Injection Pain-A Randomized Controlled Trial.

Botulinum toxin is the most commonly performed facial cosmetic procedure and pain at the injection site is a frequent patient concern. While various topical interventions have been described for analgesia, there have not been any studies comparing different techniques. We compared the use of a vibratory stimulus, ice pack application, and no intervention on injection site pain for cosmetic botulinum toxin injection. A prospective-, randomized-, individual-controlled study was conducted using a visual analog scale to assess pain. Patients received bilateral glabellar injections, with randomization into unilateral vibration, unilateral ice application, or vibration and ice on either side. We analyzed 88 injections on 22 patients. Mean visual analog scores were 26.5 (standard deviation [SD]: 23.1) among injections with vibration, 24.4 (SD: 22.9) with ice, and 29.4 (SD: 27.1) without analgesia. There was no significant difference in pain scale scores with the use of vibration, ice, or no topical anesthesia (P = .737). Further, pain scale scores did not differ significantly between medial and lateral injections nor did patients have a reduction in pain on either side of the forehead regardless of which method was used. While there may be a role for topical interventions to improve injection site analgesia, we maintain that consistently proper technique plays a greater role in improving patient tolerance. Future studies will continue to investigate the role of topical anesthesia in cosmetic facial injections and address patient-specific factors contributing to discomfort.