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PubMed2004

A survey of microbial contamination of food contact surfaces at broiler slaughter plants in Taiwan.

Microbial contamination levels at broiler slaughter plants were investigated at three major slaughter plants in Taiwan during the summer and winter. The microbial contamination levels in chicken carcasses and on food contact surfaces were examined using the swab method. The results indicated that the bacterial counts were affected by the slaughter processing plant, processes, and season (P < 0.05). The bacterial counts on food contact surfaces of the equipment before operation were not significantly lower than those after processing. Regardless of the bacterial type, bacterial counts of chicken carcasses generally decreased from the scalding step to the washing step before evisceration and then increased. The cleaning procedures for food contact surfaces should be evaluated, and special attention should be given to utensils used during processing, such as gloves, baskets, and hand tools.

Abattoirs↗

PubMed2006

[Influence of milking technique, milking hygiene and environmental hygiene parameters on the microbial contamination of milking machines].

It was the aim of this study to investigate the effect of various factors of the milking technique, milking hygiene and environment on microbial contamination of the milking machine. In 31 dairy herds, the degree of bacterial contamination was examined by taking swabs at four locations (teat cup liner, claw, short and long milk tube) before the milking procedure was started using a standardized protocol (DIN ISO 6887-1:1999). Furthermore, the total germ count was determined in the first milk entering the bulk tank as well as in the bulk tank milk following milking. For each farm, the quality of the milking process and the condition of the milking machine as well as of various environmental factors were recorded. A subjective evaluation of the status of the milking cluster or other parts of the milking machine ("good" or "moderate-poor") gave more information about bacterial contamination than the determination of age and type of material used. A temperature of the rinsing water of < 42 degrees C increased the contamination with Pseudomonas spp. and coliform bacteria. Milking clusters kept out of the cluster pick-up between milking had a higher risk of microbial contamination. Various methods of teat cleaning before milking or of postmilking teat disinfection did not affect the contamination of the milking machine and the bulk tank milk with environmental bacteria. Furthermore, type of bedding material affected bacterial contamination of milking clusters and bulk tank milk. In conclusion, our results suggest that the microbial contamination of the milking machine is not only influenced by the sanitation pro-

Animals↗

PubMed2005

Using a medium-fill simulation to evaluate the microbial contamination rate for USP medium-risk-level compounding.

PURPOSE: The estimated microbial contamination rate for complex, multiple-step, medium-risk-level compounding was studied. METHODS: The results of evaluations of the aseptic technique of pharmacists and technicians in compounding complex USP medium-risk-level sterile preparations were compiled to estimate the microbial contamination rate. The testing took place in 2002 and 2003 at a single institution and involved reconstitution of sterile dry growth medium and a series of complicated transfers of the medium from vials and ampuls to intravenous bags. The bags were incubated at 25-35 degrees C for 14 days and observed for microbial growth. RESULTS: Of 539 evaluations, 28 (5.2%) resulted in preparations that yielded microbial growth. Pharmacists' compounding resulted in a slightly lower contamination rate (4.4%) than that of technicians (6.2%). Inadvertent touch contamination may have been the principal source of the contamination. CONCLUSION: . A two-year series of 539 evaluations of the aseptic technique of pharmacists and technicians conducted with sterile growth medium and designed to simulate the compounding of USP medium-risk-level sterile preparations yielded an overall contamination rate of 5.2%.

Drug Compounding↗

PubMed2000

A prospective clinical study to investigate the microbial contamination ofa needleless connector.

Needleless connectors, which allow direct access to intravascular catheters, are widely used in clinical practice. The benefits of these devices to healthcare workers are well documented; however, the potential risk of microbial contamination and associated infection is unclear. This clinical study evaluated microbial contamination rates for a needleless connector, Connecta Clave(R) (CC(R)), as compared to a conventional three-way tap, which was connected to the hubs of central venous catheters (CVC) immediately following insertion. Patients in the study group had CC(R) attached to the three-way taps, whereas the control group had standard entry port caps. On removal (up to 72 h) the connectors were studied for microbial contamination. There was no significant difference between the number of three-way taps contaminated on the internal surface with micro-organisms in the control group with entry port caps (19/132, 14%) compared to the group with CC(R) (18/105, 17%). Sixteen percent (27/173) of the CC(R) were contaminated with micro-organisms on the internal surfaces. The external surface of 33% (27/82) of the CC(R) silicone seals were contaminated after clinical use. Micro-organisms were also isolated from 9% (8/91) of the silicone seals after disinfection. The use of this needleless connector, compared to standard caps therefore does not appear to increase the risk of infection via the internal lumen of three-way taps.

Aged↗

PubMed1987

Intrinsic and extrinsic microbial contamination of home total parenteral nutrition manufactured in eva-infusion bags (the i.v. bag).

Microbial contamination of total parenteral nutrition including fat emulsions in 1-3 litres plastic infusion bags (the i.v. bag) was studied during production in the pharmacy and administration both at home and in the hospital. Production contamination was investigated by dispensing test bags containing growth medium mixed with dextrose-salt solution. In this highly sensitive system, contamination was detected in less than 4% of cases. In-use contamination was estimated at the end of the infusion. The average contamination rate (+/- growth) in the five patients studied was 6.7% accompanied by considerable variation. Identification of the contaminants revealed that 85% of the contaminated bags contained staphylococci, indicating skin contamination. An investigation on the effect of the procedure used for attaching the infusion set on the contamination rate, was carried out with bags that contained sterile growth medium. This showed no contamination in 14 cases indicating the catheter as the most plausible source of contamination. It is concluded that both production in the community pharmacy and administration in the home are not associated with a higher microbial contamination than in central hospitals. It is, however, recommended that the microbial quality of the production process and the administration procedure are regularly monitored.

Adolescent↗

PubMed1997

Different treatment regimens to reduce microbial contamination of purified porcine islets of Langerhans.

BACKGROUND: Different treatment regimens for minimizing microbial contamination of purified porcine islets were analyzed. METHODS: Purified islets, prepared from abattoir-excised pancreata (n=26), were cultured in Hams F-12 with or without antibiotics after islet isolation. Aliquots of pancreas transport media were all contaminated with microbes (100%). Of those islets cultured with no antibiotics, 70% were contaminated, compared with 42% of the islets cultured in penicillin and streptomycin (P/S) (P>0.05). A further 20 consecutive pancreata were then randomized to saline washing (N=10) before islet isolation. Islets were then cultured in either Hams F-12 with P/S (groups C and E) or Hams F-12 with gentamicin, penicillin, and amphotericin B (G/P/A) (groups D and F). RESULTS: None of those purified islets prepared from washed pancreata and then undergoing culture in Hams F-12 with G/P/A (group F) were contaminated. This compared with 30% contamination when islets were cultured in P/S (group E). Neither antibiotic regimen compromised stimulated insulin release (P=0.13). CONCLUSIONS: In conclusion pancreas washing in saline and culture in G/P/A was shown to eradicate detectable microbial contamination of purified porcine islets isolated from abattoir-excised pancreata.

Animals↗

PubMed1992

Microbial contamination of brushes used for preoperative shaving.

Microbial contamination of brushes used for preoperative shaving was investigated. Of the 24 brushed examined, 18 were contaminated with 10(6)-10(9) colony forming units (cfu) per brush. Non-fermentative Gram-negative bacilli such as Pseudomonas aeruginosa and Xanthomonas maltophilia, and yeast-like fungi such as Candida parapsilosis were the primary contaminants. The mean bacterial count on the skin after the use of contaminated brushes (having a mean bacterial count 2.2 x 10(8) cfu) in 14 subjects was 4.6 x 10(5) cfu 25 cm-2, which was about 100 times (p less than 0.001) the control level. Contaminated brushes could not be disinfected with 80% ethyl alcohol, 0.1% sodium hypochlorite or 0.5% chlorhexidine. These findings suggest that the use of brushes should be avoided for preoperative shaving with a razor, and that sterile gauze and shaving foam should be used instead of a brush and soap.

Candida↗

PubMed1997

Minimisation of microbial contamination for potential islet xenografts using specific pathogen-free pigs and a protected environment during tissue preparation.

One major risk of islet xenotransplantation is transmission of infections. We thus compared microbial contamination during preparation of islets from 4 pigs conventionally breeded and slaughtered or 8 specific pathogen free (SPF) pigs, and different environmental conditions during pancreas excision. Pancreas harvested in a slaughterhouse (for conventional pigs) or in a protected autopsy room (for SPF pigs) were soaked in betadine solution and submitted to enzymatic digestion with collagenase. Islets were purified on histopaque gradient with a COBE 2991 processor. For each step of the process, a 10 ml aliquot was harvested and microbial contamination was analysed. For all animals, contamination of livers, which were not soaked in betadine solution, was also examined. Analysis of livers from the 4 conventional pigs showed polymicrobial contaminations (1,122 +/- 841 CFU/mg) with several species of Staphylococcus, Streptococcus, Bacillus and Enterobacteriaceae. For these conventional pigs, soaking of pancreas in betadine solution and presence of antibiotics in all media decreased the pancreatic contamination compared to hepatic contamination, but were unable to suppress it, as transport solution and crude suspension obtained after the digestion step with collagenase showed persistent contamination (9.7 +/- 2.4 and 10.5 +/- 4 CFU/ml, respectively). After islet purification by histopaque gradient, no medium remained contaminated. During analysis of the 8 SPF pigs, no liver exhibited contamination. Analysis of medium from each preparation step showed complete absence of contamination for 7 pancreases. Only one contamination with Staphylococcus simulans was observed for one pancreas in transport solution (6 CFU/ml), and persisted in digestion medium (16 CFU/ml). Finally, all purified suspensions were completely sterile. In conclusion, breeding conditions of pig islet donors, and controlled environment for pancreas excision, considerably influence the risk of microbial contamination. In order to limit the risk, SPF pigs are a suitable and compulsory source of islets.

Animals↗

PubMed2000

Monitoring the microbial contamination of beef carcass tissue with a rapid chromogenic Limulus amoebocyte lysate endpoint assay.

A chromogenic Limulus amoebocyte lysate (LAL) endpoint assay was found to be an accurate and rapid means of gauging levels of beef carcass microbial contamination within 10 min. The assay demonstrated a high correlation with the total mesophilic bacterial and coliform surface populations from inoculated beef carcass surface tissues. This assay was tested on a set of actual beef carcass surface samples (n = 121) demonstrating the utility of the chromogenic LAL test as a means of monitoring carcass microbial contamination in a near real-time fashion. Classifying the chromogenic LAL results into four contamination groups was found to be a sound means of utilizing the resultant chromogenic LAL data for detecting carcasses with high levels of microbial contamination. For beef carcass testing, this assay can be used with no instrumentation other than the required 37 degrees C incubator and, as an option, a microplate reader.

Abattoirs↗

PubMed1976

Microbial contamination of dental units and ultrasonic scalers.

Microbial contamination of the water system in 12 dental units and nine ultrasonic scalers was investigated. Water samples from ultrasonic scalers, high-speed handpieces and water syringe lines showed microbial concentrations of up to 2.6 million, 3.3 million and 190,000 colony forming units/ml respectively. Flushing the lines for 2 minutes reduced the microbial levels, but complete elimination of all bacteria was not achieved. The infectious potential of contaminated water, to the dentists and patients, particularly the compromised host is discussed.

Dental High-Speed Equipment↗

PubMed1995

Controlling microbial contamination on beef and lamb meat during processing.

The microbiological quality of carcases, meat and environmental surfaces was evaluated in commercial boning rooms processing beef and lamb. There was considerable variation in the level of microbial contamination on both carcases and meat, with counts ranging from less than 20 to 10(8)/cm2 on carcases and to 2 x 10(7)/cm2 on meat. The level of microbial contamination on meat was influenced by the level of carcase contamination at boning and by the boning process itself. Carcase contamination was the major determinant of microbiological quality, as more than 70% of carcase had microbial counts greater than 10(3)/cm2. Cutting boards were a major source for microbial dissemination during boning, particularly when carcase counts were less than 10(3)/cm2. If carcases were heavily contaminated, the contamination of processing surfaces was irrelevant in determining microbial loads on meat. Where carcase contamination was at low to moderate levels, the contribution of the boning process to the contamination on meat assumed increased significance. Under these conditions, improved sanitation of cutting surfaces in the boning room resulted in a significant reduction in microbial contamination on the surface of meat. These results can form the basis for ensuring that improvements made in carcase management before boning, to improve microbiological quality, will be preserved through attention to cutting board hygiene during boning.

Animals↗

PubMed2001

Comparison of microbial contamination of enteral feeding solution between repeated use of administration sets after washing with water and after washing followed by disinfection.

We compared microbial contamination of in-use enteral feeding solution from repeatedly used administration sets (a delivery bag and an infusion tube) after washing with water or washing followed by disinfection. In eight hospitals where administration sets were re-used after washing with water, residual solution was collected from both the delivery bag and the distal end of the infusion tube immediately after use and the microbial contamination level and microbial species found examined. The residual enteral feeding solution (28 samples) in the delivery bag grew 10(2)-10(8) colony forming units (cfu)/mL and 36 samples from the distal end of the infusion tube grew 10(2)-10(9) cfu/mL. Re-processing was changed to washing with water followed by disinfection with 0.1% (100 ppm) sodium hypochlorite, and similar examinations were performed. The residual solutions in the bag (22 samples) and in the distal end of the infusion tube (24 samples) were contaminated with < 10(1)-10(4) cfu/mL each, a significant decrease (P < 0.01, Wilcoxon U-test) compared with washing with water alone.

Disinfectants↗

PubMed1986

Reduction of microbial contamination in dental units with povidone-iodine 10%.

Ten dental units were surveyed for microbial contamination of the waterlines. All units were found to be colonized with bacteria and fungi at levels ranging from 9.0 X 10(4) to 4.1 X 10(5) CFU/mL. Undiluted povidone-iodine 10%, loaded in five experimental units for 12 hours prevented recovery of microorganisms for 3 to 14 days when used in combination with sterile water reservoirs. Use of sterile water reservoirs alone did not effectively reduce levels of microbial contamination in five control dental units.

Bacteria↗

PubMed1994

Antimicrobial factors and microbial contaminants in human milk: recent studies.

An overview of recent studies of antimicrobial factors and microbial contaminants found in human milk is presented. The incidence of gastrointestinal and respiratory infections in infants receiving human milk continues to be lower than in those not breast-fed due to the presence of specific antibody and possibly anti-adhesion factors in the milk. Whether the many other antimicrobial factors, which have been shown to be active in vitro or in animal model systems, have any influence on infant infections is still not clear. Microbial contaminants in human milk are rare, as are associated infant infections from the milk. However, some contaminants such as cytomegalovirus are commonly transferred to infants from the milk of seropositive mothers, fortunately without any adverse effects in the infants. Human T-lymphotropic virus type 1 is transferred via human milk in endemic areas, human milk being the main source of mother-to-infant transmission. While some reports suggest human immunodeficiency virus type 1 transfer may occur through human milk, this is not the predominant mode of transmission to infants.

Antibodies, Bacterial↗

PubMed2002

Microbial contamination of medicinal plants--a review.

Medicinal plants may be associated with a broad variety of microbial contaminants, which are represented by bacteria, fungi and viruses. Inevitably, this microbiological background depends on several environmental factors and exerts an important impact on the overall quality of herbal products and preparations. Risk assessment of the microbial load of medicinal plants has therefore become an important subject in the establishment of modern Hazard Analysis and Critical Control Point (HACCP) schemes. This study intends to contribute to this knowledge by giving a survey of published data regarding the microbial contamination of herbal plants, by dealing with methodological aspects and by considering the influence of different commonly used pharmaceutical preparation techniques on the microbiological status of the products. Finally, quality standards are discussed, which could be considered for guidelines and/or possible inclusion in the Ph.Eur. 2000.

Bacteria↗

PubMed1978

[Microbial contamination of dust in minimum-morbidity housings for pig rearing].

The range of the microbial contamination of 1 g of dust in minimum-morbidity pig rearing houses is from 2.9 . 10(7) to 7.6 . 10(9) in the microbes growing on meat-peptone agar (MPA), from 4.6 . 10(7) to 4.6 . 10(8) in moulds growing on the Czapek-Dox agar, from 1.4 . 10(2) to 7.0 . 10(4) in the total number of microbes growing on End's agar, and from 3.1 . 10(2) to 5.7 . 10(3) in the typically lactose-positive microbes growing on End's agar. The numbers of microbes in 1 g of dust in the conventional pig houses are close to the numbers found in pig rearing houses with minimum morbidity. However, in the moulds on the Czapek-Dox agar, the range of the microbial contamination of dust in the minimum-morbidity pig houses was much higher. The highest level of the contamination of dust with microbes was found on all types of media from houses with continual operation. It was revealed by the control of the effectiveness of disinfection in the minimum-morbidity piglet rearing section, operated on the all-in all-out basis, that in a half of the cases studied the disinfection had low effectiveness. The total number of microbes per 1 sq. cm was lower than required on the basis of research published in literature, but the occurrence rate of positive smears with lactose-positive microbes after disinfection was higher in percentual expression.

Animals↗

PubMed2006

Modeling the frequency and duration of microbial contamination events.

The frequency and duration of microbial contamination events in the environment in which ready-to-eat (RTE) foods are exposed for processing and packaging is subject to uncertainty and variability. Variability, within-model parameter uncertainty, and uncertainty regarding model selection are formally considered in modeling the frequency and duration of such contamination events by Listeria species. The estimated duration of contamination events represents a case where variability dominates with relatively little uncertainty about parameter values or model form. The estimated frequency of contamination events represents a case where there is not only substantial variability but also considerable within-model parameter uncertainty, as well as some uncertainty regarding model selection. The Bayesian Information Criterion provides a formal way of taking into account model uncertainty.

Animals↗

PubMed2003

Microbial contamination of dialysate and its prevention in haemodialysis units.

At the haemodialysis centres of nine hospitals in Japan, microbial contamination of treated water (reverse osmosis method), acid and bicarbonate concentrates, and dialysate was investigated. Among these fluids used in haemodialysis, the dialysate was most frequently contaminated and had the highest concentration of bacteria. Of 40 dialysate samples analysed, 42.5% showed a bacterial count of more than 2000cfu/mL, which was above the Association for the Advancement of Medical Instrumentation (AAMI) standard. However, among the 40 samples from 20 dialysis machines, all six dialysate samples from three dialysis machines that used an ultrafiltration membrane in the circuit before the entrance of the dialysate into the dialyser, showed a bacterial count of < or =10 cfu/mL. In addition, when an ultrafiltration membrane was used in the circuit before the entrance of the dialysate into the dialyser for four dialysis machines showing dialysate samples contaminated with 10(4)-10(5)cfu/mL the bacterial count in dialysate samples from these machines became zero. Because dialysis machines are susceptible to microbial contamination, it is necessary to take measures such as placing an ultrafiltration membrane into the circuit before the entrance of dialysate into the dialyser.

Colony Count, Microbial↗