Aim:  The aim of this study was to determine whether or not the assessment of surface cleanliness could make a contribution to visual inspections of food premises. Methods and Results:  Forty‐five premises were studied with both rapid (ATP) and traditional microbiological swabbing being used to test surfaces that either come into direct contact with prepared foods or were likely to be touched by hands during food preparation. A significant link was found between aerobic colony counts and ATP measurements. In most cases, the visual appearance of surfaces could not be used to accurately predict either microbial or ATP results. Conclusion:  This study suggests that ATP testing is a useful indicator of surface cleanliness and could be helpful to local authority officers as part of risk assessment inspections. Significance and Impact of the Study:  This study provides further evidence that visual inspection alone may not always be adequate to assess surface cleanliness. In high‐risk premises, ATP could, if appropriately targeted, help identify potential problem areas. The results are available at the time of the inspection and can be used as an on‐the‐spot teaching aid.

Aims: To determine the incidence of sporadic and apparently non-food related diarrhoea associated with Clostridium perfringens enterotoxin. Methods: Enzyme linked immunosorbent assay (ELISA) and reversed phase latex agglutination (RPLA) were used to detect C perfringens enterotoxin in faecal specimens from 818 sporadic cases of diarrhoea.Results: C perfringens enterotoxin was identified as a cause of sporadic diarrhoea in 56 of 818 (6.8%) cases. Diarrhoea was prolonged (three days or more) in most cases. Ages ranged from 3 months to 89 years, although most patients were over 60 years of age. Conclusions: These results suggest that C perfringens may be a cause of sporadic cases of diarrhoea when causes such as food consumption or cross-infection are absent, particularly in the elderly. Greiner) were coated overnight at 4°C with rabbit IgG against enterotoxin in 0O1 M sodium carbonate buffer, pH 9-8. Unbound sites were blocked by 1% bovine serum albumin (BSA) (Sigma) in 0-1 M sodium carbonate buffer, pH 9-8, incubated overnight at 4°C. Test extracts were incubated undiluted with 0 05% Tween 20 (Sigma) and after dilution 1 in 10 in PBS, 0 05% Tween 20 for 75 minutes at room temperature. Each extract was also incubated with neutralising antibody. After washing, rabbit anti-enterotoxin conjugated to horseradish peroxidase in PBS, 0-05% Tween 20, 1% BSA was incubated for two hours at room temperature. The enzyme substrate solution contained 0-5 mg/ml orthophenyldiamine in citrate phosphate buffer (2-43 ml 0-1 M citric acid, 2-57 ml 0-2 M sodium phosphate, and 5-0 ml distilled water). The reaction was stopped by adding 100 ,ul 4 M H2so4 and the absorbance at 492 nm was read in a Titertek Multiskan MCC plate reader. Wells containing no absorbed antibody or no test extract were included in each plate and gave an absorbance of less than 0I10.A standard curve on each plate was used to calculate the enterotoxin concentration. This covered the full range of absorbance with enterotoxin concentrations between 0 1 ng/ml and 100 ng/ml. The coefficient of variance (100 x standard deviation/mean) for intra-assay measurement of enterotoxin concentration was 2-5%. The coefficient of variation of interassay measurements of enterotoxin concentration was between 4-4% and 11-2%.C perfringens spore counts were determined following alcohol shock.' Pure cultures of C perfringens isolated from enterotoxin positive faeces were sent to the PHLS Food Hygiene Laboratory for serological typing using a set of 609 on 7 May 2018 by guest. Protected by copyright.

SUMMARYThree groups of premises (butchers' shops, supermarkets and general dealers) which sell raw and cooked meats were compared. Salmonellas were not detected, but Escherichia coli, and to a lesser degree Staphylococcu-s aureus and Streptococcus faecalis, were widely distributed in all three groups of premises. Contamination of hands, towels and nail brushes was related to poor working practices. The presence of E. coli or Str. faecalis on slicing machines was associated with contamination of meat samples. A number of wiping cloths were heavily contaminated with E. coli, and many also contained Clostridium perfringens. Few premises provided written cleaning plans, and in many cases staff did not receive an adequate training in food hygiene. The use of disinfectants as part of the cleaning process did not necessarily reduce the level of bacterial contamination. In general there was poor correlation between microbiological results and a visual inspection made by an environmental health officer. The possible reasons for this finding are discussed.

SUMMARYA comparison of five methods of cleaning Formica surfaces contaminated with bacteria dried in milk has been carried out. A standardized procedure was developed, and impression plates were found to be at least as sensitive as a swab-rinse method for detecting bacteria on the surfaces. The most satisfactory results were obtained with one type of disposable alcohol-impregnated wipe and with a detergent/hypochlorite solution applied with paper. A reusable cloth impregnated with disinfectant initially performed well against all test organisms, but was less reliable against Staphylococcus aureus and Streptococcus faecalis, after the cloth had been used and rinsed several times. The importance of introducing methods to reduce the high risk of cross-contamination presently associated with the use of wiping cloths in catering premises is stressed.

Summary This review looks at the contribution of microbiological sampling to the safety of retail foods in England and Wales. It compares sampling methods available and assesses the value of testing as part of outbreaks of foodborne disease, as part of routine management by local authorities, as part of work done or commissioned by the food industry, and as part of research. It confirms that microbiological testing has a role during outbreaks as it makes a significant contribution to help identify foods and other areas of greatest risk for future study. The review suggests that routine testing by local authorities is often of limited use and could be improved by more targeted surveillance. Testing could be better used to validate primary control methods, such as Hazard Analysis and Critical Control Point (HACCP) system. Any public health benefit from testing in the food industry is often restricted by client confidentiality. Microbial research on foods is important as it can lead to significant improvements in safety. Current microbiological methods are slow and, in future, rapid molecular methods may make an even bigger contribution to the control of foodborne disease.