Post-acute COVID-19 complications in UK doctors: results of a cross-sectional survey.

BACKGROUND: As a consequence of their occupation, doctors and other healthcare workers were at higher risk of contracting coronavirus disease 2019 (COVID-19), and more likely to experience severe disease compared to the general population. However, systematic information on post-acute COVID complications in doctors is very limited. AIMS: This study aimed to determine the symptoms, perceived determinants, health and occupational impact, and consequent needs relating to post-acute COVID complications in UK doctors. METHODS: An online cross-sectional survey was distributed to UK doctors self-identifying as having Long COVID or other post-acute COVID complications. RESULTS: Of 795 responses, 603 fulfilled the inclusion criteria of being a UK-based medical doctor experiencing one or more post-acute COVID complications. Twenty-eight per cent reported a lack of adequate Respiratory Protective Equipment at the time of contracting COVID-19. Eighteen per cent of eligible respondents reported that they had been unable to return to work since acquiring COVID. CONCLUSIONS: Post-acute COVID (Long COVID) in UK doctors is a substantial burden for respondents to our questionnaire. The results indicated that insufficient respiratory protection could have contributed to occupational disease, with COVID-19 being contracted in the workplace, and resultant post-COVID complications. Although it may be too late to address the perceived determinants of inadequate protection for those already suffering with Long COVID, more investment is needed in rehabilitation and support of those afflicted.

Beta-blockers and mechanical dyssynchrony in heart failure assessed by radionuclide ventriculography.

BACKGROUND: Radionuclide ventriculography (RNVG) can be used to quantify mechanical dyssynchrony and may be a valuable adjunct in the assessment of heart failure with reduced ejection fraction (HFrEF). The study aims to investigate the effect of beta-blockers on mechanical dyssynchrony using novel RNVG phase parameters. METHODS: A retrospective study was carried out in a group of 98 patients with HFrEF. LVEF and dyssynchrony were assessed pre and post beta-blockade. Dyssynchrony was assessed using synchrony, entropy, phase standard deviation, approximate entropy, and sample entropy from planar RNVG phase images. Subgroups split by ischemic etiology were also investigated. RESULTS: An improvement in dyssynchrony and LVEF was measured six months post beta-blockade for both ischemic and non-ischemic groups. CONCLUSIONS: A significant improvement in dyssynchrony and LVEF was measured post beta-blockade using novel measures of dyssynchrony.

Radionuclide ventriculography phase analysis for risk stratification of patients undergoing cardiotoxic cancer therapy.

BACKGROUND: Accurate diagnostic tools to identify patients at risk of cancer therapy-related cardiac dysfunction (CTRCD) are critical. For patients undergoing cardiotoxic cancer therapy, ejection fraction assessment using radionuclide ventriculography (RNVG) is commonly used for serial assessment of left ventricular (LV) function. METHODS: In this retrospective study, approximate entropy (ApEn), synchrony, entropy, and standard deviation from the phase histogram (phase SD) were investigated as potential early markers of LV dysfunction to predict CTRCD. These phase parameters were calculated from the baseline RNVG phase image for 177 breast cancer patients before commencing cardiotoxic therapy. RESULTS: Of the 177 patients, 11 had a decline in left ventricular ejection fraction (LVEF) of over 10% to an LVEF below 50% after treatment had commenced. This patient group had a significantly higher ApEn at baseline to those who maintained a normal LVEF throughout treatment. Of the parameters investigated, ApEn was superior for predicting the risk of CTRCD. Combining ApEn with the baseline LVEF further improved the discrimination between the groups. CONCLUSIONS: The results suggest that RNVG phase analysis using approximate entropy may aid in the detection of sub-clinical LV contraction abnormalities, not detectable by baseline LVEF measurement, predicting a subsequent decline in LVEF.

Nitrogen losses in anoxic marine sediments driven by Thioploca-anammox bacterial consortia.

Ninety per cent of marine organic matter burial occurs in continental margin sediments, where a substantial fraction of organic carbon escapes oxidation and enters long-term geologic storage within sedimentary rocks. In such environments, microbial metabolism is limited by the diffusive supply of electron acceptors. One strategy to optimize energy yields in a resource-limited habitat is symbiotic metabolite exchange among microbial associations. Thermodynamic and geochemical considerations indicate that microbial co-metabolisms are likely to play a critical part in sedimentary organic carbon cycling. Yet only one association, between methanotrophic archaea and sulphate-reducing bacteria, has been demonstrated in marine sediments in situ, and little is known of the role of microbial symbiotic interactions in other sedimentary biogeochemical cycles. Here we report in situ molecular and incubation-based evidence for a novel symbiotic consortium between two chemolithotrophic bacteria--anaerobic ammonium-oxidizing (anammox) bacteria and the nitrate-sequestering sulphur-oxidizing Thioploca species--in anoxic sediments of the Soledad basin at the Mexican Pacific margin. A mass balance of benthic solute fluxes and the corresponding nitrogen isotope composition of nitrate and ammonium fluxes indicate that anammox bacteria rely on Thioploca species for the supply of metabolic substrates and account for about 57 ± 21 per cent of the total benthic N2 production. We show that Thioploca-anammox symbiosis intensifies benthic fixed nitrogen losses in anoxic sediments, bypassing diffusion-imposed limitations by efficiently coupling the carbon, nitrogen and sulphur cycles.

A novel oral tracer procedure for measurement of habitual myofibrillar protein synthesis.

RATIONALE: Conventionally, myofibrillar protein synthesis is measured over time periods of hours. In clinical studies, interventions occur over weeks. Functional measures over such periods may be more representative. We aimed to develop a novel method to determine myofibrillar protein fractional synthetic rate (FSR) to estimate habitual rates, while avoiding intravenous tracer infusions. METHODS: Four healthy males were given 100 g water enriched to 70 Atom % with (2)H2O as a single oral bolus. Vastus-lateralis needle biopsies were performed and plasma samples collected, 3-13 days post-dose. (2)H enrichment in body water was measured in plasma using continuous flow isotope ratio mass spectrometry (IRMS). Myofibrillar protein was isolated from muscle biopsies and acid hydrolysed. (2)H enrichment of protein-bound and plasma-free alanine was measured by gas chromatography (GC)/pyrolysis/IRMS. Myofibrillar protein FSR was calculated (% day(-1)). RESULTS: The tracer bolus raised the initial enrichment of body water to 1514 ppm (2)H excess. Water elimination followed a simple exponential. The average elimination half-time was 8.3 days. Plasma alanine, labelled during de novo synthesis, followed the same elimination kinetics as water. The weighted average myofibrillar protein FSR from the four subjects was 1.38 % day(-1) (range, 1.0-1.9 % day(-1) ). CONCLUSIONS: Myofibrillar protein FSR was measured in free-living healthy individuals over 3-13 days. Using a single oral (2)H2O bolus, endogenous labelling of alanine occurred in a predictable manner giving estimates of synthesis comparable with published values. Furthermore, the protocol does not compromise the ability to measure other important metabolic processes such as total energy expenditure.

Quality Assessment of Longissimus and Semitendinosus Muscles from Beef Cattle Subjected to Non-penetrative and Penetrative Percussive Stunning Methods.

This study provides a comparative analysis of the effects of pre-slaughter penetrative and non-penetrative stunning and post-slaughter stunning on meat quality attributes in longissimus lumborum (LL) and semitendinosus (ST) muscles in heifers. Ten animals were assigned to each of four treatment groups: i) animals were subjected to conventional Halal slaughter (a clean incision through the structures at the front of the upper neck - the trachea, oesophagus, carotid arteries and jugular veins) and post-cut penetrating mechanical stun within 10 to 20 s of the neck cut (Unstunned; US); ii) high power non-penetrating mechanical stunning followed by the neck cut (HPNP); iii) low power non-penetrating mechanical stunning followed by the neck cut (LPNP); and iv) penetrative stunning using a captive bolt pistol followed by the neck cut (P). For each carcass, muscle samples were removed within 45 min of slaughter, portioned and analysed for pH, cooking loss, water holding capacity (WHC), tenderness (WBS), lipid oxidation (TBARS) and color, over a two week storage period. Stunning did not affect pH and cooking loss. Significant differences in water holding capacity, tenderness, lipid oxidation and color were present at different storage time points. HPNP stunning resulted in lower WHC and color values, particularly lightness (L*), higher TBARS values and peak force values compared with those stunned using LPNP, P and US. These adverse effects on quality were mostly encountered in the ST muscle. In conclusion, the meat quality achieved using P, LPNP and US treatments was comparable, and no treatment stood out as considerably better than another.

Takotsubo cardiomyopathy: an Australian single centre experience with medium term follow up.

BACKGROUND: Takotsubo cardiomyopathy (TC) is increasingly recognised in patients presenting with features of acute coronary syndrome. We present a single centre experience of TC with medium term follow up. METHODS: Fifty-two consecutive patients presenting with a diagnosis of TC were included. The clinical presentation, complications, baseline and follow-up echocardiograms and cardiac magnetic resonance imaging were analysed. RESULTS: Fifty-one patients were female. A stressful event preceded presentation in 37 (71%) patients. Chest pain was the most common symptom (83%). Two patients presented with an out-of-hospital cardiac arrest. ST segment elevation (40%) and global T wave inversion (44%) were the most frequent electrocardiogram changes. Left ventricular assessment demonstrated typical apical ballooning in 41 patients and 11 patients demonstrated the mid-wall variant. In-hospital complications occurred in 11 patients (21%) and included acute pulmonary oedema (n = 2), cardiogenic shock (n = 5); two of whom had a significant left ventricular outflow gradient, atrial fibrillation (n = 1), left ventricular thrombus (n = 2) and a cerebrovascular event (n = 2). Left ventricular function at presentation and follow up was compared in 40 patients. The mean ejection fraction in this group at presentation was 47% (20-70%) compared with that at follow up of 63% (44-76%). There were no significant complications or recurrences at follow up. CONCLUSIONS: While TC is a reversible condition with low rates of complications and recurrence at follow up it is, as demonstrated in our cohort, associated with significant in-hospital morbidity in a proportion of patients.

Annual prevalence estimation of lymphatic malformation with a cutaneous component: observational study of a national representative sample of physicians.

BACKGROUND: Lymphatic malformations (LMs) represent a potentially life-threatening, rare disease of the lymphatic system characterized by development of abnormal vessels, outpouchings, or cysts filled with lymphatic fluid. There are three morphologic types of LMs based on the size of the individual cysts: macrocystic (typically > 2 cm), microcystic (generally < 2 cm), and mixed (includes aspects of both). Macrocystic LMs typically exist beneath the skin and often can involve vascular components and/or organs. Microcystic LMs often have a cutaneous component and clinically present with lymphorrhea, bleeding, pain, itching, malodor, and functional deficits. There are no treatments approved by the US Food and Drug Administration (FDA) for either macrocystic or microcystic lymphatic malformations. The totality of the epidemiologic literature for LM is limited to the incidence of the disease among various birth cohorts. This is the first nationally representative study to estimate the national managed prevalence for patients with microcystic LM or combined LM with a cutaneous component annually across physician specialties likely to manage this condition. We conducted a retrospective observational survey of a nationally representative sample of patient-care physicians in the United States most likely to manage lymphatic malformations with a cutaneous component (LMC). Once recruited, target physicians participated via an electronic questionnaire. We weighted study physician self-estimates of the number of LMC patients treated in the past 12 months to reflect the specialists' corresponding proportion in the national universe. All patient information was anonymous; no personally identifiable information was collected. RESULTS: Of the 420 physicians who visited the study website, 316 agreed to be screened and to participate (75.2% participation rate). Our survey results indicated the estimated number of unique annually managed LMC patients by target specialists is 79,920 (CI 66,600-93,250). This number corresponds to managed prevalence of 24.1 LMC patients per 100,000 population (CI 19.6/100,000-28.4/100,000). CONCLUSIONS: The study indicates that while rare, LMC affects a substantial number of people in the US (79,920) who are being managed by one or more specialists. By better understanding the prevalence of people living with LMC who require treatment, efforts to both increase disease awareness and to identify underserved populations in need of potential new treatments can be better focused.

Marking to weaning production aspects of lambs provided with NSAID analgesia compared with lambs receiving no analgesia at the time of elastrator ring marking.

The provision of analgesia at the time of marking has been adopted by the Australian sheep industry, but data on production benefits are lacking. In the current study, alternate lambs were provided with either meloxicam (non-steroidal anti-inflammatory drug [NSAID], n = 781) or no analgesia (NONE, n = 822) at the time of ring castration and tail docking. Six distinct management groups of lambs were studied. Lambs were weighed immediately before marking and then again at weaning. There was no significant effect of treatment on average daily gain between marking and weaning in cross-bred lambs. In Merino lambs, average daily gain was 5 g/day lower (P < 0.005) in lambs receiving NSAID, but this may not be biologically significant. Lamb losses were significantly (P < 0.05) lower in the NSAID group (1.1%) than in the NONE group (2.7%). This observation is worth validating in larger studies, particularly considering that lamb mortality is a significant cost to production and welfare concern.

Can central hexagon peak latency provide a clue to fixation within the mfERG.

The mfERG has proven to be a useful tool in determining central retinal and macular function. It is, however, reliant on good subject co-operation and fixation. This cannot always be guaranteed due to visual impairment or poor co-operation. Whilst a change in fixation is easy to identify with camera monitoring of the subject, a small eccentric fixation can be difficult to notice or quantify. Whilst the problem of fixation can be obviated by stimulating the retina directly with SLO (Scanning Laser Ophthalmoscope), this is expensive and a certain amount of expertize in optics is required to properly stimulate the retina. In this study, peak latency of response was investigated to see whether it changed across the retina and whether this measure could be used to help assess fixation. Eighteen normal eyes were stimulated using a 60 Hz CRT monitor with only 2 hexagons, one central and one peripheral. These hexagons were presented at three stimulation rates, fast (no filler frames between steps of the m-sequence) and slow (4 and 7 black filler frames between each step of the m-sequence), under all conditions significantly increased central hexagon latencies were noted. In a smaller experiment with 19 hexagons and only 4 subjects, it was noted a significant delay in latency was observed in ring 1 compared to ring 2 and 3 with central fixation, but not when the subjects fixed mid-peripheral and in the periphery to slow stimulation, showing that the central hexagon response was only delayed in the central hexagon when there was adequate fixation. This study suggests that latency could provide a clue to fixation particular at slow rates thereby improving the quality and confidence of recordings made clinically.

Tolerance and sensitization to the effects of cocaine use in humans: a retrospective study of long-term cocaine users in Philadelphia.

In the effort to develop medications to combat addiction, researchers have developed models that attempt to describe the neurobiological process of cocaine dependence. It has not, however, yet been determined which of these models, if any, best fits the behaviors and experiences of patients. This project retrospectively evaluated changes in patients' experiences with cocaine over time in order to clarify the model that best fits clinical observations. In 2005 and 2007, 100 treatment-seeking, long-term cocaine users were recruited from an urban university-based treatment center in Philadelphia, PA, United States. Each participant was administered the "Cocaine History Questionnaire" which asked them to describe the initiation and escalation of their cocaine usage, changing reward perceptions, and effects of intoxication at certain points in their drug use careers. This data was then analyzed using repeated measures, examining the within subject differences in reported information over the time points. We found evidence that while the amount of drug used increases, self-reported euphoria decreases while negative symptoms associated with cocaine use also increase. The data provide preliminary evidence for the hedonic dysregulation model of addiction. Limitations and implications of the study are discussed in the conclusion.

Potential for the cross-contamination of the hides of cattle while they are held in lairage.

Foodborne pathogens that may contaminate the carcase are often found on the hides of cattle presented for slaughter for human consumption, and can be transferred from animal to animal during the immediate preslaughter phase. This study quantifies the opportunities for such cross-contamination to occur during lairage of cattle. Cattle were most active in the first 10 minutes of holding, when at 2.5 m(2) or less space allowance per animal there were 12.55 animal-to-animal and 0.99 animal-to-wall contacts per minute, compared with 8.17 and 0.60 per minute, respectively, in the subsequent 20 minutes. During holding, contact between animals can be reduced by manipulating the stocking density. When the animals were given 2.5 m(2) or more each, there were 9.63 animal-to-animal contacts per minute over 30 minutes holding, whereas at 5 m(2) or more, there were only 1.71 contacts per minute. Whatever the space allowance, animal-to-wall contacts were 0.66 to 0.73 per minute over 30 minutes' holding. When space allowance is optimised, contacts with the lairage structure become more important than contacts between animals. The immediate preslaughter handling equipment (race, crush and stun box) was a significant source of potential indirect cross-contamination.

Development of a microwave stunning system for cattle 2: Preliminary observations on behavioural responses and EEG.

DTS: Diathermic Syncope® (DTS) is a novel system for rendering animals insensible prior to slaughter, utilizing microwave energy to induce a rise in temperature in the brain to a point at which the animal is expected to lose consciousness. During development and optimisation of the system, two trials were carried out utilizing non-anaesthetized adult cattle, to gather data on behavioural outcomes and EEG changes following energy application. In trial1, ten cattle received DTS treatments (high energy >290 kJ, n = 3; low energy <200 kJ, n = 4; and intermediate 200 < 290 kJ, n = 3), and seven received captive bolt stunning, prior to exsanguination. In trial 2, following improvements to the efficiency of energy delivery, 20 cattle received DTS (200-360 kJ). Post treatment EEG was characterized by seizure-like activity and reductions in 95% spectral edge and median frequencies; with EEG suppression persisting for at least 80 s up to over 4 min post treatment application. Animals showed: Loss of posture, Loss of corneal responses; Loss of withdrawal response (pinprick); Eye staring, not following movement. The animals remained unresponsive to stimuli for up to 4 min post DTS, and behavioural expression of distress was not observed. Seventeen of the 30 animals showed indications of returning reflex responses after 100 s post treatment, suggesting that animals receiving lower energy applications may recover from the stun.

Efficacy of meloxicam in a pain model in sheep.

OBJECTIVE: To evaluate the efficacy of the non-steroidal anti-inflammatory drug, meloxicam, in alleviating pain and inflammation and on production-related variables in a model of sterile acute inflammation in sheep. METHODS: Groups of 12 mature Merino ewes received 0, 0.5, 1.0 or 1.5 mg/kg meloxicam subcutaneously 90 min before injection of 0.1 mL turpentine subcutaneously on the anterior aspect of the proximal phalanx of a forelimb. Pain- and inflammation-related variables were assessed at -18, 3, 6, 9, 12, 24, 48 and 72 h relative to meloxicam administration. Daily feed intake and body weight change 7 days later were also assessed. Pain-related variables measured were weight borne on each forelimb, lameness score, time each forelimb was raised in a 20-s interval and tolerance to a noxious mechanical stimulus. Inflammation-related variables measured were skin temperature, limb circumference, body temperature, plasma haptoglobin concentration and peripheral blood leucocyte parameters. RESULTS: Meloxicam was effective in improving all pain-related variables. A dose-dependent response was seen between 0 and 1.0 mg/kg, with no additional benefit provided by 1.5 mg/kg. At a dose rate of 1.0 mg/kg, meloxicam improved weight borne on the turpentine-treated limb by 14%, reduced the time the treated limb was held in a non-weight-bearing posture by 46%, reduced the lameness score by 58% and improved tolerance to pressure by 52%. No significant effects of meloxicam on inflammatory variables or appetite were observed. CONCLUSIONS: Using a validated pain model, the data suggested that 1.0 mg/kg meloxicam provided significant analgesic benefits to sheep.

A curve fitting approach to estimate the extent of fermentation of indigestible carbohydrates.

BACKGROUND: Information about the extent of carbohydrate digestion and fermentation is critical to our ability to explore the metabolic effects of carbohydrate fermentation in vivo. We used cooked (13)C-labelled barley kernels, which are rich in indigestible carbohydrates, to develop a method which makes it possible to distinguish between and to assess carbohydrate digestion and fermentation. MATERIALS AND METHODS: Seventeen volunteers ingested 86 g (dry weight) of cooked naturally (13)C enriched barley kernels after an overnight fast. (13)CO(2) and H(2) in breath samples were measured every half hour for 12 h. The data of (13)CO(2) in breath before the start of the fermentation were used to fit the curve representing the digestion phase. The difference between the area under curve (AUC) of the fitted digestion curve and the AUC of the observed curve was regarded to represent the fermentation part. Different approaches were applied to determine the proportion of the (13)C-dose available for digestion and fermentation. RESULTS: Four hours after intake of barley, H(2)-excretion in breath started to rise. Within 12 h, 24-48% of the (13)C-dose was recovered as (13)CO(2), of which 18-19% was derived from colonic fermentation and the rest from digestion. By extrapolating the curve to baseline, it was estimated that eventually 24-25% of the total available (13)C in barley would be derived from colon fermentation. CONCLUSION: Curve fitting, using (13)CO(2)- and H(2)-breath data, is a feasible and non-invasive method to assess carbohydrate digestion and fermentation after consumption of (13)C enriched starchy food.

Expandable metal stent placement for benign colorectal obstruction: outcomes for 23 cases.

BACKGROUND: Self-expanding metal stents (SEMS) are an established treatment for palliation of malignant colorectal strictures and as a bridge to surgery for acute malignant colonic obstruction. Patients with benign colonic strictures may benefit from stent placement, but little data exist for this indication. METHODS: All cases of colonic stent placement identified from a prospectively collected gastrointestinal database from April 1999 to August 2006 were reviewed. During the study period, 23 patients with benign obstructive disease underwent endoscopic SEMS placement. The etiologies of the stricture were diverticular/inflammatory (n = 16), postsurgical anastomotic (n = 3), radiation-induced (n = 3), and Crohn's (n = 1) disease. All strictures were located in the left colon. Five patients had an associated colonic fistula. Uncovered Enteral Wallstents or Ultraflex Precision Colonic stents (Boston Scientific) were endoscopically placed in all but one patient. RESULTS: Stent placement was technically successful for all 23 patients, and obstruction was relieved for 22 patients (95%). Major complications occurred in 38% of the patients including migration (n = 2), reobstruction (n = 4), and perforation (n = 2). Of these major complications, 87% occurred after 7 days. Four patients did not undergo an operation. Of the 19 patients who underwent planned surgical resection, 16 were successfully decompressed and converted from an emergent operation to an elective one with a median time to surgical resection of 12 days (range, 2 days to 18 months). Surgery was delayed more than 30 days after stent placement for six of these patients. Of the 19 patients who underwent a colectomy, 8 (42%) did not need a stoma after stent insertion. CONCLUSIONS: SEMS can effectively decompress high-grade, benign colonic obstruction, thereby allowing elective surgery. The use of SEMS can offer medium-term symptom relief for benign colorectal strictures, but this approach is associated with a high rate of delayed complications. Thus, if elective surgery is planned, data from this small study suggest that it should be performed within 7 days of stent placement.

Marine plastics threaten giant Atlantic Marine Protected Areas.

There has been a recent shift in global perception of plastics in the environment, resulting in a call for greater action. Science and the popular media have highlighted plastic as an increasing stressor [1,2]. Efforts have been made to confer protected status to some remote locations, forming some of the world's largest Marine Protected Areas, including several UK overseas territories. We assessed plastic at these remote Atlantic Marine Protected Areas, surveying the shore, sea surface, water column and seabed, and found drastic changes from 2013-2018. Working from the RRS James Clark Ross at Ascension, St. Helena, Tristan da Cunha, Gough and the Falkland Islands (Figure 1A), we showed that marine debris on beaches has increased more than 10 fold in the past decade. Sea surface plastics have also increased, with in-water plastics occurring at densities of 0.1 items m-3; plastics on seabeds were observed at ≤ 0.01 items m-2. For the first time, beach densities of plastics at remote South Atlantic sites approached those at industrialised North Atlantic sites. This increase even occurs hundreds of meters down on seamounts. We also investigated plastic incidence in 2,243 animals (comprising 26 species) across remote South Atlantic oceanic food webs, ranging from plankton to seabirds. We found that plastics had been ingested by primary consumers (zooplankton) to top predators (seabirds) at high rates. These findings suggest that MPA status will not mitigate the threat of plastic proliferation to this rich, unique and threatened biodiversity.

Managing safety and quality through the red meat chain.

To successfully manage food safety and quality risks in meat production, a holistic approach is required. The ideal would be a fully integrated assurance system, with effective controls applied at all stages. However, the red meat industry is by nature somewhat fragmented, and a truly integrated system is not at present achievable in all but a few operations. This paper describes a variety of assurance initiatives, and explores how targeted research and development can be used to augment assurance programmes by providing underpinning knowledge, using the Australian beef and lamb industry as an example.

An evaluation of simple cleaning methods that may be used in red meat abattoir lairages.

Concrete tiles artificially contaminated with field strains of Escherichia coli and Salmonella kedougou, with and without the presence of bovine faecal matter, to simulate visually clean and visually dirty surfaces respectively, were cleaned using a specially designed mechanical rig. Cleaning was carried out using (1) water under mains pressure, (2) water under pressure, (3) water under pressure with a proprietary sanitising agent, (4) steam under pressure and combinations of (5) mains water followed by steam under pressure or (6) water under pressure followed by steam under pressure. Thirty replicates of each of visually clean and visually dirty concrete surfaces were cleaned using each method. Where there was no faecal matter, the use of a proprietary sanitiser at maximum recommended concentration, or the application of steam under pressure gave greater reductions in microbial contamination than the use of mains or a pressure wash. Where the surface was visually contaminated with the faecal material, the use of a pressure wash followed by immediate steam application gave reductions in microbial contamination comparable with the use of a proprietary sanitiser at maximum recommended concentration. The use of steam alone on a visually dirty surface was not an effective means of reducing microbial contamination. A small pilot trial under commercial conditions ranked the efficacy of cleaning treatments as follows: pressure washing followed immediately by steam application was the best method of cleaning a holding pen floor, followed by use of a sanitising agent at the greatest concentration recommended by the manufacturer, and then by pressure washing alone. Pressure washing followed by a delayed steam application appeared to give a poor final result on the surface.

Construction, management and cleanliness of red meat abattoir lairages in the UK.

A survey of a large number of UK abattoirs was conducted via a questionnaire designed to obtain information on (i) throughput and species slaughtered; (ii) construction materials used; (iii) use and type of bedding and (iv) details of cleaning/sanitation regimes. A representative group of abattoirs were selected on the basis of the responses to the questionnaire, and the lairage at these plants investigated through enumeration of Escherichia coli remaining after routine cleansing operations. The aim of this study was to enable identification of "common lairage practices" and to assess the general status of the lairage hygiene and effectiveness of lairage cleaning in commercial UK abattoirs. The study shows that microbial contamination often remains in UK lairage holding pens after routine cleaning operations. It would appear that there are significant differences in the effectiveness of lairage cleaning programmes at commercial abattoirs, and that the stun-box-roll-out areas are often cleaned to a better standard than the holding areas. As a result of persistence of microbial contamination in the lairage, there is a possible risk of foodborne pathogens persisting in the environment and potentially contaminating animals and carcasses processed on subsequent days.