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PubMed1997

Autotransfusion--bacterial contamination during hip arthroplasty and efficacy of cefuroxime prophylaxis. A randomized controlled study of 40 patients.

40 patients undergoing primary hip arthroplasty, given autologous processed blood transfusion, were randomized a receive no antibiotic prophylaxis (group A, n 20) or cefuroxime (1.5 g single injection; group B, n 20). Bacterial contamination at various steps in the autotransfusion procedure was assessed in liquid and solid culture media. The operation field and the wound drainage blood were never contaminated either of the groups but some of the suction tips were. Parts of the Vacufix blood collection bags of group A contained bacteria, but none in group B. Processed red blood cell concentrates in both groups showed bacterial growth. Greater blood loss did not increase the contamination rate in general. Isolated bacteria included the species Staphylococcus epidermidis, coagulase-negative staphylococci and Propionibacteria in both groups, but with different cell counts. In addition, Corynebacterium bovis et minutissimum and Moraxelle were identified in group A. In conclusion, autologous blood transfusion was a safe procedure. If contamination occurred, the bacterial count was low, and the bacteria of low pathogenicity. Antibiotic prophylaxis with cefuroxime reduced this contamination of suction tips and collection bags and limited the transfer of autologous blood products.

Antibiotic Prophylaxis↗

PubMed1982

Noncitrinin toxicity of Penicillium citrinum contaminated corn.

Day-old white Leghorn chicks were fed P. citrinum-contaminated corn at 3.88, 7.75, 31, or 62% levels in the ration for a period of 5 weeks. High treatment levels (31 and 62%) of contaminated corn in the ration caused severe growth depression, high mortality, and significant decreases in feed consumption. Necrosis of periportal and centrilobular hepatocytes, glomerular atrophy and hyperplasia, degeneration and necrosis of tubular cells, lymphoid depletion, suppression of hematopoiesis, necrosis of pancreatic acinar cells, and a cardiac and skeletal myopathy were observed microscopically in chicks fed 31 and 62% contaminated corn in the rations. Low levels of contaminated corn in the ration (3.88 and 7.75%) caused few clinical effects; however, liver and kidney changes were observed microscopically. Ultrastructural observation of affected tissues showed swelling of mitochondria, dilatation of the endoplasmic reticulum, increased numbers of autophagic vacuoles and paramyelin figures, and lipoprotein peroxidation of organelles. The toxin (s) present in the P. citrinum contaminated ration have not been identified.

Animals↗

PubMed1987

Effects of feeding deoxynivalenol (DON, vomitoxin)-contaminated wheat to female White Leghorn chickens from day old through egg production.

White Leghorn chickens one day of age were fed starter and grower diets containing either a control (noncontaminated) wheat diet or a naturally contaminated deoxynivalenol (DON) wheat diet (18 mg DON/kg) from 1 day of age to the onset of egg production. The hens were then placed on their respective layer diets of control wheat or DON-contaminated wheat (18 mg DON/kg) for six 28-day egg production periods. Feeding the DON-contaminated diet did not significantly influence body weights during the growing or the laying phases. Overall, hen-day egg production and egg weights were significantly higher for hens receiving the DON diet. Feeding DON contaminated wheat caused no significant changes in percent shell, albumen height, percent fertility, percent hatch of fertile eggs, percent hatch of eggs set, or weight of chicks at hatch. There were slight, although significant, changes in shell weight and shell thickness and in some serum chemistry values. There were no significant differences in the hematology parameters measured or in prothrombin times. None of the eggs collected from hens fed the control and the DON-contaminated wheat diet contained detectable quantities of DON. Microscopic examination of sections of the liver, kidney, and proventriculus of control and treated hens revealed no unusual histopathology. The results indicate that feeding DON at relatively high levels beginning at 1 day of age and continuing through six egg production periods had only slight effects on the parameters measured.

Animal Feed↗

PubMed2006

Morphological significance of cladosporium contaminants on materials and utensils in contact with food.

Cladosporium contaminants on materials and utensils that come into contact with food were morphologically investigated. The most common contaminants, C. cladosporioides and C. sphaerospermum, were detected on the samples. The morphological changes of the Cladosporium species were investigated by using stereoscopic, optical light, fluorescent, and scanning electron microscopes. Microscopically the Cladosporium contaminants were observed as aggregated dark brown spots, strongly pigmented, irregularly swollen, and in long chains. Using fluorescent microscopy, the Cladosporium mycelia were clearly stained with fluorescein diacetate as viable cells, but the old cells were mostly non-viable, as shown by staining with propidium iodide. The dynamics of the morphological changes showed that the penetrating mycelia were closely attached to the surface of the materials and utensils under investigation. These results provide information about the significance of Cladosporium contamination on materials and utensils in contact with food and may contribute to the control of fungal contamination.

Cladosporium↗

PubMed2000

Listeria monocytogenes contamination pattern in pig slaughterhouses.

Ten low-capacity slaughterhouses were examined for Listeria by collecting a total of 373 samples, of which 50, 250, and 73 were taken from carcasses, pluck sets, and the slaughterhouse environment, respectively. Six slaughterhouses and 9% of all samples were positive for Listeria monocytogenes. Of the samples taken from pluck sets, 9% were positive for L. monocytogenes, the highest prevalence occurring in tongue and tonsil samples, at 14% and 12%, respectively. Six of 50 (12%) carcasses were contaminated with L. monocytogenes. In the slaughterhouse environment, L. monocytogenes was detected in two, one, one, and one sample originating from the saws, drain, door, and table, respectively. Carcasses were contaminated with L. monocytogenes in those two slaughterhouses, where the mechanical saws, used for both brisket and back splitting, were also positive for L. monocytogenes. A total of 58 L. monocytogenes isolates were characterized by pulsed-field gel electrophoresis typing. The isolates were divided into 18 pulsotypes, 15 of which were detected in pluck sets. In two slaughterhouses, where the carcasses were contaminated with L. monocytogenes, the same pulsotypes were also recovered from splitting saws. In addition, identical pulsotypes were recovered from pluck sets. Our findings indicate that L. monocytogenes of tongue and tonsil origin may contaminate the slaughtering equipment that may in turn spread the pathogen to carcasses. Thus, it is of the utmost importance to follow good manufacturing practices and to have efficient cleaning and disinfection procedures to prevent equipment being contaminated with L. monocytogenes.

Abattoirs↗

PubMed2001

Continuous online processing of fecal- and ingesta-contaminated poultry carcasses using an acidified sodium chlorite antimicrobial intervention.

The objective of this study was to determine the effectiveness of the combined use of an inside-outside-bird-washer for the removal of visible contamination and an online acidified sodium chlorite (ASC) spray system in reducing microbial levels on contaminated poultry carcasses. Specifically, we attempted to determine if this technique (referred to as continuous online processing [COP]) would (i) eliminate the need for offline reprocessing of contaminated carcasses, (ii) meet Zero Fecal Tolerance standards, and (iii) attain significant reductions in titers of some of the commonly found bacterial species. Carcasses were sampled for Ercherichia coli, Salmonella, and Campylobacter at five stations along the processing lines in a series of five commercial plant studies to compare the efficacy of the COP system to that of offline processing. The microbiological quality of fecally contaminated carcasses was found to be significantly better following COP treatment (E. coli, 0.59 log10 CFU/ml; Salmonella, 10.0% incidence) than after standard offline reprocessing (E. coli, 2.37 log10 CFU/ml; Salmonella, 31.6% incidence). Zero Fecal Tolerance requirements were met by all but 2 (0.2%) of the 1.127 carcasses following COP. COP also significantly reduced the titers of Campylobacter; residual titers were 1.14 log10 CFU/ml (49.1% incidence) following COP, compared to 2.89 log10 CFU/ml (73.2% incidence) in carcasses that underwent offline reprocessing. These results support the combined use of an inside-outside-bird-washer for the removal of visible contamination and an online ASC spray system to reduce microbial levels in commercially processed poultry.

Animals↗

PubMed2003

On-farm and postharvest processing sources of bacterial contamination to melon rinds.

Multistate and international foodborne illness outbreaks, particularly involving cantaloupe and often involving rare Salmonella spp., have increased dramatically over the past 13 years. This study assessed the sources and extent of melon rind contamination in production fields and at processing and packing facilities. In the spring of 1999, cantaloupe (Cucumis melo L. [reticulatus group] cv. Cruiser) sampled from two sites in the Rio Grande River Valley showed that postharvest-processed melon rinds often had greater plate counts of bacterial contaminants than field-fresh melons. Cantaloupe in the field had 2.5 to 3.5 log CFU g(-1) rind total coliforms by aerobic plate counts, whereas washed melons had 4.0 to 5.0 log CFU g(-1). In the fall of 1999, coliforms on honeydew melons (C. melo [inodorous group] cv. Honey Brew) ranged from 2.6 to 3.7 log CFU g(-1) after processing, and total and fecal coliforms and enterococci never fell below 2.5 log CFU g(-1). A hydrocooler at another site contaminated cantaloupe rinds with up to 3.4 log CFU g(-1) total and fecal enterococci; a secondary rinse with chlorinated water incompletely removed these bacteria. Sources of coliforms and enterococci were at high levels in melon production soils, especially in furrows that were flood irrigated, in standing water at one field, and in irrigation water at both sites. At one processing facility, wash water pumped from the Rio Grande River may not have been sufficiently disinfected prior to use. Because soil, irrigation water, and process water were potential sources of bacterial contamination, monitoring and management on-farm and at processing and packing facilities should focus on water quality as an important control point for growers and packers to reduce bacterial contamination on melon rinds.

Colony Count, Microbial↗

PubMed2003

Male-specific coliphages as an additional fecal contamination indicator for screening fresh carrots.

The objective of this study was to evaluate the efficacy of male-specific (F+) coliphages as a fecal-contamination indicator for fresh carrots. The prevalence of specific pathogens and indicator organisms on the surface of carrots obtained from a farm, truck, and processing shed was studied. Twenty-five carrot samples collected from each of these locations were washed, and aliquots of the wash were analyzed for the presence of F+ coliphages, Escherichia coli, Salmonella, and Shigella. Additionally, the Salmonella isolates were genotyped using pulsed-field gel electrophoresis (PFGE). Our studies detected the presence of F+ coliphages, E. coli, and Salmonella on carrots. All samples, however, tested negative for Shigella. Although none of the carrot samples from the field were positive for E. coli, one sample was positive for Salmonella, and another was positive for F+ coliphages. From the truck, two carrot samples (8%) were positive for Salmonella, four (16%) were positive for F+ coliphages, and four (16%) were positive for E. coli. None of the carrot samples from the processing shed were positive for Salmonella. However, 2 carrot samples (8%) were positive for E. coli, and 14 carrot samples (56%) were positive for F+ coliphages. The PFGE results suggest that there were three distinct Salmonella genotypes among the carrot samples from the truck and that the Salmonella isolates identified on carrot samples from the field and truck locations were different. Microbiological screening of fresh produce such as carrots (which can be exposed to fecal contaminants in soils and water) should ensure the detection of both viral and bacterial contaminants. Overall, in this study, F+ coliphages were detected in 25% of the carrot samples, compared to E. coli (8%), Salmonella (4%), and Shigella (0%). The results suggest F+ coliphages can serve as a conservative indicator of fecally associated viruses on carrots. This suggests that in addition to E. coli screening, F+ coliphages should be included when produce such as carrots that are vulnerable to fecal contaminants are screened. Since the detection of specific enteric viral pathogens is expensive, screening for viral indicators of fecal contamination using F+ coliphages can be an economical approach to providing an additional level of assurance about the microbiological quality of fresh carrots.

Coliphages↗

PubMed2003

Optimal fluorescence excitation and emission bands for detection of fecal contamination.

Fecal contamination of food products is a critical health issue. To test the feasibility of the use fluorescent techniques to detect fecal contamination, fluorescence excitation and emission characteristics of fecal matter from cows, deer, swine, chickens, and turkeys in the UV to far-red regions of the spectrum were evaluated. To allow the optimization of the detection of fecal contamination on animal carcasses and cut meats, emission-excitation spectra of the feces were compared with spectra for animal meats. The feedstuffs for the swine, chickens, and turkeys were also analyzed. Excitation at approximately 410 to 420 nm yielded the highest level of fluorescence for both feces and feedstuffs. Emission maxima were in the red region (at 632 nm for chicken feces and at 675 nm for the feces of the other species). The major constituent responsible for emission at 632 nm was tentatively identified as protoporphyrin IX; emission at 675 nm most likely emanates from chlorophyll a or its metabolites. Animal meats emitted strong fluorescence in the blue-green regions, but no emission peaks were observed in the red region for these meats. These results suggest that fluorescence emissions from naturally occurring chlorophyll a and its metabolites are good markers for fecal contamination and that with excitation at 410 to 420 nm, the responses of fecal matter can easily be differentiated from the responses of animal meats. We suggest that the detection of fecal contamination can be enhanced by requiring a minimum chlorophyll a content in the finishing diets of all farm animals.

Animal Feed↗

PubMed2004

Impact of intervention strategies on Listeria contamination patterns in crawfish processing plants: a longitudinal study.

Two ready-to-eat crawfish processing plants were monitored for 2 years to study the impact of Listeria control strategies, including employee training and targeted sanitation procedures, on Listeria contamination. Environmental, raw material, and finished product samples were collected weekly during the main processing months (April to June) and tested for Listeria spp. and Listeria monocytogenes. Before implementation of control strategies (year 1), the two processing plants showed Listeria spp. prevalences of 29.5% (n = 78) in raw, whole crawfish, 5.2% (n = 155) in the processing plant environment, and 0% (n = 78) in finished products. In year 2, after plant-specific Listeria control strategies were implemented, Listeria spp. prevalence increased in raw crawfish (57.5%, n = 101), in the processing plant environment (10.8%, n = 204), and in the finished product (1.0%, n = 102). Statistical analysis showed a significant increase in Listeria spp. prevalence (P < 0.0001) and a borderline nonsignificant increase in L. monocytogenes prevalence (P = 0.097) on raw material in year 2. Borderline nonsignificant increases were also observed for Listeria spp. prevalence in environmental samples (P = 0.082). Our data showed that Listeria spp. prevalence in raw crawfish can vary significantly among seasons. However, the increased contamination prevalence for raw materials only resulted in a limited Listeria prevalence increase for the processing plant environment with extremely low levels of finished product contamination. Heat treatment of raw materials combined with Listeria control strategies to prevent cross-contamination thus appears to be effective in achieving low levels of finished product contamination, even with Listeria spp. prevalences for raw crawfish of more than 50%.

Animals↗

PubMed2004

Effect of prechill fecal contamination on numbers of bacteria recovered from broiler chicken carcasses before and after immersion chilling.

Paired carcass halves were used to test whether fecal contamination of skin during processing of broiler chickens can be detected by increased bacterial counts in samples taken before and after immersion chilling. In each of three trials, six freshly defeathered and eviscerated carcasses were cut in half, and a rectangle (3 by 5 cm) was marked with dots of ink on the breast skin of each half. One half of each pair was chosen randomly, and 0.1 g of freshly collected feces was spread over the rectangle with a spatula. After 10 min, both halves were sprayed with tap water for 10 to 15 s until feces could no longer be seen in the marked area. Both halves were sampled with a 1-min carcass rinse and were then put in a paddle chiller with other eviscerated carcasses for 45 min to simulate industrial immersion chilling. Immediately after chilling, each carcass half was subjected to another 1-min rinse, after which the skin within the rectangle was aseptically removed from the carcass halves and stomached. Rinses of fecally contaminated halves had significantly higher Enterobacteriaceae immediately before chilling, but there were no differences in coliform and Escherichia coli counts. After chilling, there were no differences in Enterobacteriaceae, coliform, and E. coli counts in rinse or skin samples from the paired carcass halves. Correlations were generally poor between counts in rinse and skin samples but were significant between prechill and postchill rinses for both control and fecally contaminated halves. Correlations were also significant between counts in rinses of control and contaminated halves of the same carcass after chilling. Bacterial counts in postchill carcass rinses did not indicate that fecal contamination occurred before chilling.

Animals↗

PubMed2006

Cryptosporidium contamination in harvesting areas of bivalve molluscs.

Cryptosporidium contamination was evaluated in areas in Galicia (northwestern Spain) where bivalve molluscs are harvested. Galicia is the main mussel-producing region in Europe. Data were collected on water contamination of effluents that are discharged into these areas. Cryptosporidium spp. were detected by immunofluorescence microscopy and molecular methods in 71% of the river water samples (n = 7), 64% of raw sewage samples (n = 11), 50% of effluents from wastewater treatment plants (n = 16), and 29.3% of the mussel samples (Mytilus galloprovincialis, n = 184). Cryptosporidium parvum was identified in all samples of contaminated mussels, Cryptosporidium muris was found in three samples of effluent from wastewater treatment plants, and Cryptosporidium baileyi was found in a sample of raw sewage. Further studies are needed to determine the parasitological quality of water in these shellfish harvesting and recreational areas. Cryptosporidium could be a public health risk from consumption of raw or undercooked contaminated molluscs and use of contaminated waters for recreational purposes.

Animals↗

PubMed2006

Influence of eggshell condensation on eggshell penetration and whole egg contamination with Salmonella enterica serovar enteritidis.

Shells of agar-filled and whole eggs were inoculated with 10(3) to 10(4) CFU of Salmonella enterica serovar Enteritidis per eggshell. The agar-filled eggs were used to study bacterial eggshell penetration, and the whole egg results were used to characterize contamination of the egg contents. In each group, half of the eggs were stored for 21 days at 20 degrees C and 60% relative humidity (RH), and the other half was stored for 24 h at 6 degrees C and then for 20 days at 20 degrees C. The latter conditions resulted in condensation on the eggshell for 30 min from the moment the eggs were placed in the 20 degrees C chamber. Taking into account the ages at which hens were studied (39, 53, and 67 weeks), an average of 62% of the eggshells with condensate were penetrated compared with 43% for the control group; this difference was significant (P < 0.01). No significant difference in whole egg contamination was found; 18% of the control eggs were contaminated compared with 22% of the condensate eggs. Whole egg contamination was significantly higher for eggs from the hens at an older age (67 weeks). This difference probably was not due to a higher penetration potential because differences were not observed for the corresponding agar-filled eggs. Condensation on the eggshell seemed to encourage bacterial penetration of the eggshell but had a smaller impact on whole egg contamination.

Age Factors↗

PubMed1993

Residual bacterial contamination on reusable pulse oximetry sensors.

BACKGROUND: An early study demonstrated that standard cleaning techniques did not adequately disinfect reusable pulse oximetry sensors that had been intentionally contaminated with high titers of pathogenic microorganisms. This current study evaluated patient-ready sensors being used in hospitals, by testing them for bacterial contamination. METHODS: Reusable pulse oximetry sensors from 15 hospitals throughout the United States were tested. Each sensor was deemed by the hospital to be ready for patient use, and it had been prepared for use according to hospital procedures. Patient-contact areas of each sensor were swabbed, and the swabs were analyzed for bacterial contamination using standard testing procedures. This study had two stages, and different sensors were tested in each stage. In the "bacterial-growth stage," swabs were evaluated for bacterial contamination but organisms were not identified; in the "identification stage," bacterial species were identified. RESULTS: Forty-four sensors were evaluated, 16 in the bacterial-growth stage and 28 in the identification stage. Bacteria were cultured from 29 of the 44 sensors (66%), including 20 that had been cleaned with alcohol or an antibacterial/antiviral agent. Among the isolated organisms were Staphylococcus aureus, Staphylococcus haemolyticus, Enterococcus faecalis, and Klebsiella oxytoca. Bacterial contamination was found on sensors from 12 of the 15 participating hospitals. CONCLUSIONS: These data demonstrate the need to define effective cleaning methods for reusable sensors, and we are currently conducting such studies. The data also suggest that disposable patient-dedicated sensors may be the most appropriate choice when infection control is of particular concern.

Bacterial Infections↗

PubMed1999

[Monitoring of microbial contamination of stick wound in swine carcasses].

This study was done to evaluate the microbial contamination by Salmonella spp., Escherichia coli, fecal coliforms, and total aerobic count of the stick wound of swine carcasses. The effectiveness of trimming the stick wound in the 2 Québec slaughterhouses visited was evaluated. A bacteriological analysis was done on 276 stick wounds. Results indicated that, before trimming, 0.9% stick wounds were contaminated by Salmonella spp. Contamination by coliforms was observed in 40.6% of samples, and 27.7% were positive for E. coli. After trimming the stick wounds, 1.1% were contaminated by Salmonella spp., 34.1% were contaminated by coliforms, and 26.2% were positive for E. coli. The results showed that trimming contributes to reducing significantly the bacterial total count at the site and that the bacterial load at this site was less important than that found on the brisket.

Abattoirs↗

PubMed1999

Incidence of contamination of preserved saline solutions during normal use.

PURPOSE: To ascertain the incidence of microbial contamination of preserved contact lens saline solutions with normal patient use. METHODS: Eight different brands of preserved saline were dispensed to 40 patients attending optometric practices in the Sydney area. After specific periods of time (7 to 28 days), the samples were collected and the solution bottle nozzles and contents underwent microbial analysis. RESULTS: The overall contamination rate was approximately 26% for contents only and 55% for nozzles of preserved saline solutions. This rate remained constant for all periods of use. Coagulase-negative Staphylococci were most frequently isolated. No Acanthamoebae were isolated. Saline preserved with ethylene-diamine-tetraacetic acid (EDTA) in conjunction with sorbic acid showed the highest percentage of sterility. CONCLUSIONS: The results of this study show that preserved saline became contaminated with gram-positive bacteria. This is in contrast to our previously published paper using unpreserved saline, where contamination was predominantly with gram-negative bacteria. The overall contamination rates with preserved saline were lower than for unpreserved saline.

Contact Lens Solutions↗

PubMed1976

Epidemiology of organomercury poisoning in Iraq. I. Incidence in a defined area and relationship to the eating of contaminated bread.

A survey was carried out in a defined area in rural Iraq where there had been many cases of organomercury poisoning following the consumption of bread contaminated by mercury, in order to determine the true incidence of the disorder. The results were compared with those obtained from a similar rural area from which few cases had been reported. A questionnaire was used to determine the amount of contaminated bread eaten and the frequency of symptoms; a simple clinical examination was performed and blood and hair samples were collected for estimation of total mercury concentration. Of 700 people over the age of 5 years in the high-exposure area, 66% admitted to having eaten contaminated bread, while none of the 864 persons in the low exposure area had done so. The mean period during which contaminated bread was eaten was 32 days, but some people had eaten it for as long as 3 months. A mean of 121 loaves was eaten, the maximum being 480 loaves. For the mean number of loaves the intake of methylmercury was likely to have been between 80 mg and 250 mg, but the people who had consumed the largest amount of contaminated bread may have ingested up to 1 000 mg of methylmercury over a 3-month period. Of those with signs of alkylmercury poisoning at the time of the survey, 80% had eaten more than 100 loaves, and 53 (71%) out of 75 persons who had eaten more than 200 loaves showed some evidence of poisoning.The incidence rate for poisoning was estimated at 271 per 1 000; this figure includes a mortality rate of 59 per 1 000, 32 per 1 000 cases with severe disability, 41 per 1 000 cases with mild or moderate disability and 138 per 1 000 cases with only subjective evidence of poisoning at the time of the study.

Adolescent↗

PubMedDate not supplied

Origin, result and measurement of USP "essentially free" inspection for visible contaminating particles.

The efficient mass production of pharmaceuticals requires scientifically replicable measurements. The measurements, in turn, must be capable of description in words and terms that can be universally understood and applied beyond national, corporate, or measurement laboratory boundaries. A notable present exception has been the required evaluation of visible particle contamination in injectable products. Beginning in USP23 <788> (1) and continuing in USP 24 there is official recognition that the results of the nondestructive inspection for "visible" particles cannot be described in simple terms. Although the call for injectable products to be free of any visible particle contamination has been repeated, variability in the results of the nondestructive inspection for contaminating particles has been officially recognized. This recognition is expressed in one sentence, "Injectable solutions, including solutions constituted from sterile solids intended for parenteral use, should be essentially free from particles that can be observed on visual inspection." This phrasing describes a probabilistic contaminating particle inspection result. Methodology with which to evaluate the effectiveness of the probabilistic manual, semi- or fully-automated inspection for contaminating particles in sealed containers has been well tested for the last 21 years. This paper provides a brief, nonmathematical review of the core concepts that are used.

Drug Contamination↗