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PubMed2004

Effect of intestinal content contamination on broiler carcass Campylobacter counts.

Intestinal contents may contaminate broiler carcasses during processing. The objective of this study was to determine what effect various levels of intestinal contents had on the numbers of Campylobacter detected in broiler carcass rinse samples. Eviscerated broiler carcasses were collected from the shackle line in a commercial processing plant immediately after passing through an inside/outside washer. Broiler carcasses were cut longitudinally into contralateral halves using a sanitized saw. Cecal contents from the same flock were collected, pooled, homogenized, and used to contaminate carcass halves. Paired carcass halves were divided into groups of eight each, and then cecal contents (2, 5, 10, 50, or 100 mg) were placed onto one randomly selected half of each carcass, while the corresponding half of the same broiler carcass received no cecal contents. Campylobacter counts from carcass halves with cecal contamination were compared to the uncontaminated halves of the same carcasses using a paired t test. Carcass halves with 5 mg or more of surface cecal contamination had significantly higher numbers of Campylobacter than those without (P < 0.01). Carcass halves contaminated with only 5 mg of cecal contents had an average of 3.3 log CFU Campylobacter per ml of rinse, while corresponding uncontaminated carcass halves had 2.6 log CFU Campylobacter per ml of rinse. These data indicate that even small (5 mg) amounts of cecal contents can cause a significant increase in the numbers of Campylobacter on eviscerated broiler carcasses. Therefore, it is important to keep such contamination to a minimum during processing.

Animals↗

PubMed2006

Hot boning of intact carcasses: a procedure to avoid central nervous system self-contamination in beef and beef products.

Compared with traditional boning of split refrigerated carcasses, hot boning of intact carcasses (the removal of meat from the skeleton prerigor) provides several commercially important cuts, may improve quality and reduce refrigeration costs, and may reduce the contamination of carcasses with central nervous system (CNS) tissue. In a comparative study of hot boning of intact and split carcasses, the CNS tissue contamination of intact carcasses was negligible (as measured with the CNS-related proteins glial fibrillary acidic protein and S-100 protein), but split carcasses were highly contaminated. The same trends were observed for dissection worktables used during the boning process. Most current boning plants have processing lines that are organized for boning carcass quarters, where the carcasses, in addition to transversal division, also are split horizontally. This part of the boning process was incorporated in the design of our study. Nine of the 18 intact carcasses were split horizontally between thoracic vertebrae 10 and 11 before they were hot boned. CNS tissue contamination was not detected on the carcass site related to this procedure. The amount of CNS tissue contamination was similar in boned cuts and minced meat from split and intact carcasses, except in the forerib. Boning of split carcasses appears to reduce CNS tissue contamination significantly to a level comparable to that of intact hot-boned carcasses.

Animals↗

PubMed2006

Daily variability of Listeria contamination patterns in a cold-smoked salmon processing operation.

An understanding of Listeria transmission and contamination patterns in processing environments of ready-to-eat foods is critical for improving control of Listeria monocytogenes. A cold-smoked fish processing operation was the site used to study variability in Listeria contamination in a processing environment associated with a ready-to-eat food product throughout one production week (five consecutive days). Intensive testing was conducted on finished products and environmental samples collected at the beginning, middle, and end of each working day. A total of 20 finished products and 22 to 36 environmental samples were collected at each sampling time, and an additional 12 environmental samples were collected on days 4 and 5. Overall, a total of 782 samples, 300 finished products and 482 environmental samples, were tested. All samples were collected from processing steps after smoking, including skinning, trimming, slicing, staging, and packing. A total of 28 finished and 57 environmental samples (9.3 and 11.8%, respectively) were positive for Listeria spp. (including 1 and 5 samples positive for L. monocytogenes, respectively). DNA sequencing of the sigB gene allowed differentiation of eight Listeria subtypes. Listeria prevalence varied significantly between days, and a high prevalence in both environmental samples and finished products on day 3 was likely associated with a point source contamination event by a single Listeria welshimeri subtype. There were no consistent differences in Listeria prevalence among samples collected from the beginning, middle, and end of the production day, but subtype data often revealed unique contamination patterns for samples collected at different times of a given day. Listeria contamination patterns and prevalences were highly variable between days and within a given day. These findings indicate that chance events play an important role in the contamination of finished products, thus complicating efforts to define Listeria transmission patterns in processing environments associated with ready-to-eat foods.

Animals↗

PubMed1986

Parenteral handling precaution: particulate introduction resulting from needle sheath contamination.

The purpose of this in vitro experiment was to determine if inadvertent needle cap nicking would introduce particulate contamination. After a preliminary observation (n = 21), a more thorough confirmatory experiment (n = 28) was performed. Twenty-four of 28 needles were contaminated before, and 18 of 28 needles after, entry into a Latex injection port; 5 of these 18 needles remained contaminated post sterile water injection and withdrawal from the port. Since 19 of 24 contaminated needles lost their contamination within the simulated injection system, it was proposed that inadvertent needle cap particulate contamination to needle shafts may be introduced into in vivo tissue or delivered intravascularly.

Equipment Contamination↗

PubMed2000

Reducing the risk of bacterial contamination of cellular blood components.

Transfusion-associated septic reactions occurring during or following the transfusion of cellular blood components was one of the earliest recognised complications of allogeneic blood transfusions. The presence of bacteria in cellular blood products thus has been a problem for many decades and currently it is the most common microbiological cause of transfusion-associated morbidity and mortality. Transfusion-associated septic reactions due to contaminated platelet concentrates appear to be much more common than those due to red cell concentrates. The prevalence of contaminated cellular blood products (red cells and platelets) is approximately 1 in 2,000. However, the transfusion to a recipient of a contaminated blood product may not be associated with morbidity, because many contaminated blood product units contain only few bacteria and such transfusions may be innocuous to the recipient. In other instances, contaminated blood product units may contain large numbers of virulent bacteria and endotoxins, and their transfusion may be associated with significant morbidity and may even be lethal to the recipient. The prevalence of severe episodes of transfusion-associated sepsis has not been clearly established, but is probably of the order of 1 in 50,000 for platelet units and 1 in 500,000 for red blood cell units transfused. As a result of the increased recognition that such transfusion-associated septic episodes can occur, a variety of measures have been proposed to try to prevent and/or control the rate of contamination of blood products.

Bacteria↗

PubMed2000

[Residual bacterial contamination of rhinoscopes used in ENT consultation after cleaning with a pad impregnated with a disinfectant].

INTRODUCTION: The duration of the official disinfection procedure of a Hopkins rhinoscope agreed by the hospital hygiene authorities may be a handicap in a busy ENT consultation. A shortened procedure is sometimes used, but without risk assessment. OBJECTIVE: To determine the risk of contamination of the endoscope used for rhinoscopy after simple manual cleaning with a pad impregnated with a disinfectant solution (Neosabenyl). PATIENTS AND METHOD: In 60 patients undergoing rhinoscopy at our ENT policlinic, a nasal swab as well as the endoscope were examined bacteriologically. The nasal physiological flora and specifically Staphylococcus aureus were semiquantitatively analysed on each specimen. In 50 patients, the rhinoscopes were simply cleaned with an impregnated pad, whereas in 10 patients the official disinfection procedure with glutaraldehyde was applied. RESULTS: 25 out of the 50 endoscopes (50%) which were manually cleaned with the impregnated pad, were still contaminated with bacteria. Among the 12 (20%) identified healthy carriers of S. aureus, 7 (58%) showed a rhinoscope still contaminated with S. aureus after cleaning with the pad. The overall risk of contaminating the following patient with S. aureus is 14%. None of the 10 endoscopes cleaned and disinfected with glutaraldehyde were contaminated. CONCLUSIONS: Simple manual cleaning and disinfection with an impregnated pad is insufficient and carries the risk of contaminating the following patient. This emphasises the need to follow the recommended cleaning and disinfection procedures even in a small or busy practice.

Carrier State↗

PubMed2001

[Microbiological contamination of intraoperatively collected erythrocyte concentrate in mechanical autotransfusion in tumor surgery].

Intraoperative autotransfusion is an effective method of the autologous haemotherapy. Gamma irradiation of the salvaged erythrocyte concentrates leads to inactivation of malignant cells and allows retransfusion in oncologic surgery. The risk of microbiological contamination of the autologous blood product has not been systematically studied in this field of surgery. During the evaluation of intraoperative autotransfusion in oncologic surgery at the University Hospital of Leipzig, the salvaged blood of 46 patients who underwent tumour surgery (urology, gynaecology and neurosurgery) was processed to a washed erythrocyte concentrate with a Cell Saver 5 or a Haemolite 2 (Haemonetics). Specimens for microbiological studies were taken from the area of surgery, the reservoir bottle of the autotransfusion system and the salvaged erythrocyte concentrates. The investigation with plate cultures and the identification of microorganisms were performed according to standard procedures of microbiological diagnosis. The ethics committee of the University Hospital of Leipzig approved the study protocol. We found a microbiological contamination in 10 of 46 salvaged erythrocyte concentrates (22%), above all the growth of saprophytes (Streptococcus, Staphylococcus and Neisseria species). We also identified bacteria which have their habitats in the intestinal tract (E. coli and Enterococcus). The highest rate of microbial contaminated erythrocyte concentrates was found in urologic oncosurgery (37%). In neurosurgery (laminectomy and craniotomy including tumour extirpation), there was no bacterial growth in the salvaged erythrocyte concentrate. Intraoperative autotransfusion should be avoided during surgery touching the urinary tract, e.g. prostatectomy and cystectomy. In neurosurgery, it seems to be safe as far as microbiological contamination is concerned. To assess the real risk of microbiological contamination of the salvaged erythrocytes, more investigations are necessary to determine not only the extent and nature of contamination but also the clinical effects.

Adult↗

PubMed2001

[Vaccination of calves with contaminated batches of bovine herpes virus 1 vaccines did not result in infection with bovine virus diarrhea virus].

The aim of the experiment was to study whether bovine herpesvirus 1 (BHV1) marker vaccine batches known to be contaminated with bovine virus diarrhoea virus (BVDV) type 1 could cause BVD in cattle. For this purpose, four groups of cattle were used. The first group (n = 4 calves, the positive control group), was vaccinated with vaccine from a batch contaminated with BVDV type 2. The second group (n = 4 calves, the negative control group), was vaccinated with vaccine from a batch that was not contaminated with BVDV. The third group (n = 39 calves), was vaccinated with a vaccine from one of four batches contaminated with BVDV type 1 (seronegative experimental group). The fourth group (n = 6 seropositive heifers), was vaccinated with a vaccine from one of three batches known to be contaminated with BVDV type 1. All cattle were vaccinated with an overdose of the BHV1 marker vaccine. At the start of the experiment, all calves except those from group 4 were seronegative for BVDV and BHV1. The calves from group 4 had antibodies against BVDV, were BVDV-free and seronegative to BHV1. After vaccination, the positive control calves became severely ill, had fever for several days, and BVDV was isolated from nasal swabs and white blood cells. In addition, these calves produced antibodies to BVDV and BHV1. No difference in clinical scores of the other groups was seen, nor were BVDV or BVDV-specific antibody responses detected in these calves; however, they did produce antibodies against BHV1. The remainder of each vaccine vial used was examined for the presence of infectious BVDV in cell culture. From none of the vials was BVDV isolated after three subsequent passages. This indicates that BVDV was either absent from the vials or was present in too low an amount to be isolated. Thus vaccination of calves with vaccines from BHV1 marker vaccine batches contaminated with BVDV type 1 did not result in BVDV infections.

Animals↗

PubMedDate not supplied

An assessment for the presence of bacterial contamination of Venturi principle atomizers in a clinical setting.

BACKGROUND: Venturi principle atomizers have been criticized for potential contamination and disease transmission when used for nasal application. A recent laboratory study reported a high rate of contamination of these atomizers after their tips were immersed and sprayed into a broth containing Staphylococcus aureus. The objective of this study was to determine whether the Venturi-type atomizers used regularly at a busy referral center for sinonasal disorders were contaminated with bacteria. METHODS: Fifteen Venturi-type atomizers containing 2% lidocaine (four bottles), 4% lidocaine (three bottles), or 0.05% oxymetazoline (eight bottles) were sprayed onto blood agar plates. All atomizer bottles had been in routine use in a tertiary rhinology clinic for 1 month. The contents within each bottle's reservoir also were cultured. Thus, the total sample size was 30 plates. Then, the plates were incubated at 35 degrees C for 48 hours and then at room temperature for 72 hours. RESULTS: Three of our 30 plates grew one colony each of Gram-positive bacilli, Gram-positive cocci, and Staphylococcus species. CONCLUSION: The rare growth of any bacteria seen in our samples could as likely represent contamination during processing and handling of the plates as contamination of the atomizers themselves. Thus, Venturi-type atomizers may not have a high potential contamination risk, which has been suggested by previous reports.

Colony Count, Microbial↗

PubMed1991

Contaminant identification: the importance of thorough interviewing techniques.

The exact name of a contaminant is of extreme importance to the poison information specialist (SPI) in order to make a correct assessment of the poisoning exposure and to recommend proper treatment modalities. Incorrect contaminant information could lead to a serious and possibly fatal mistake on the part of the SPI. Thorough and effective interviewing techniques must be employed to avoid errors. We conducted a prospective study to determine how often misinformation is provided to the SPI at the time of the initial contact with the poison center. Over a 6-mo period 159 calls were identified in which the original caller mistakenly identified the contaminant. Fifty-two (33%) of these calls were received from health care professionals and 107 (67%) were from the lay public. Drug names were improperly reported in 80 cases, cleaning products in 26, cosmetics 14 times, general products 19, chemicals 7, rodenticides 8, and plants were incorrectly identified in 5 cases. In 110 of these cases, proper identification of the contaminant changed the assessment and also the treatment recommendations made by the SPI. Errors in contaminant identification occurs more frequently than is realized by poison center professionals. It is imperative to have the caller clarify the contaminant name by checking the container, when available, and supplying the SPI with as much information as possible. It is equally important that the SPI employ precise interviewing techniques to obtain information to avoid a serious error in assessment and treatment of the poisoned victim.

Drug Contamination↗

PubMedDate not supplied

[Studies of microbiological contamination of ultrasonic apparatus used in pediatric aerosol therapy].

It was found that inflating tube is most rarely contaminated with microorganisms during the use of ultrasonic inhalator TUR USI 70. Glass cylinder is contaminated more frequently whereas a diaphragm, aerosol preparation, inhaling mask and a pipe joining it with the device are contaminated most frequently. Sporadic contamination of the inflating tube indicate an efficient work of air filters while frequent contamination of the diaphragm, aerosol preparation and glass cylinder prove that the contamination is caused by a coupling fluid. It was also found that ultrasound exerts a destructive effect on microorganisms in the aerosol preparation. The investigations have shown that the inhaling mask and tubes joining it with the device should be changed before each use while the other parts of an inhalator and aerosol preparation may be changed once per 15 inhalations. It was also noted that disinfection of different parts of the device by a 2% aqueous glutaric aldehyde (30 minutes at room temperature) is efficient in about 95%.

Air Microbiology↗

PubMed1989

[The significance of the contamination of dental care articles. The results of a field study].

Permissible conclusions both from recent available literature and our own field-study results concerning the problematic nature of microbial contamination of dental hygiene articles and the resulting possible health hazard for the consumer can be summarized as follows: Manufacturing practices as are given in the basic instructions for production sites of the cosmetic industry, render a possible degree of microbial contamination. This largely rules out the danger of infection of the consumer upon acquisition of the dental hygiene product. Secondary contamination of these products, as inevitably is the case during use of dental hygiene articles, leads to microbial colonization especially of toothbrush bristles. The extent of this colonization depends at least partially upon the utilization age of the toothbrush. Also for this reason a toothbrush should be replaced by a new one after period of three months, six months at the latest and in all cases of inflammatory changes of the mouth and throat region. The contamination of both the glass or plastic container used for rinsing the teeth after brushing or for gargling can be held within certain limits by dry storage. Only in exceptional cases do mouthwashes show a small degree of contamination. Provided they contain antimicrobial substances, no therapeutically serviceable possibilities worth mentioning follow for the reduction of oropharyngeal flora. Microbial colonization of toothpastes as a result of secondary contamination following use is observed only in exceptional cases due to their preservative content. Significant germination of stagnated residual water in waterpicks often occurs, achieving germ counts up to more than 10(7) cfu per ml. Moreover, waterpicks can represent a biotope for Pseudomonas aeruginosa, and should be used neither by patients with open wounds or mucous membrane lesions in the oropharyngeal area, nor by patients with reduced immune resistance. Manufacturers of waterpicks are urged to impede or prevent the stagnation of residual water more effectively by introducing constructive improvements. Denture and retainer cleansing agents presently on the market display a sufficient antimicrobial effect within the frame of their application, however do not meet the standards set for disinfectants. Dental hygiene products are without relevance for the epidemiology of Legionnaires' disease.

Bacteria↗

PubMed1985

Viral contamination of intradermal skin test syringes.

Intradermal skin tests are often performed using a common syringe with multiple needles. Bacterial contamination of intradermal skin test syringes can occur as a result of apparent siphoning caused by needle changing. The bacterial contamination of the syringe can be prevented by flushing the contaminated needle prior to changing. In this study, two different needle changing techniques were examined using a polio virus contaminant. Viral contamination of the syringe was not prevented by flushing the infected needle prior to removal. All syringes were contaminated with virus regardless of needle changing technique. We, therefore, cannot recommend the continued use of a common syringe for intradermal skin tests between patients regardless of needle changing technique.

Equipment Contamination↗

PubMed1985

Microbial contamination potential of sterile disposable plastic syringes.

The contamination potential of sterile disposable plastic syringes was evaluated after subjecting the syringes to both simulated in-use conditions and an intentional microbial challenge. Lots of 20 Luer-lock syringes in 10 or 12-cu cm and 20- or 30-cu cm sizes from three manufacturers were tested. Sampling was conducted using 30-ml vials of sterile aerobic culture media containing 14C-labeled substrates. Microbial contamination was confirmed by both visual observation of the turbidity caused by colonization and instrumental detection of 14CO2 caused by the microbial metabolism of 14C-substrates. No contamination of 120 samples was found after the ribbed plunger shaft was grasped by a bare, unprepared dry hand during five cycles of filling and injecting the medium into the vials without removing the needles from the stoppers. When this sampling technique was applied to the syringes inoculated on the upper piston surface with Bacillus subtilis suspension, a 100% contamination rate was observed in 120 samples each under both positive and negative in-vial pressure. Grasping the ribbed plunger shaft of disposable plastic syringes with a dry bare hand did not compromise the sterility of the syringe contents in this study; however, this practice should be avoided when possible. Personnel should absolutely avoid introducing fluid-borne microbial contaminants into the distal barrel end of these syringes because the contents are readily labile to contamination under these conditions.

Bacillus subtilis↗

PubMed1982

Evaluation of three methods for detecting low-level bacterial contamination in intravenous solutions.

The accuracy of three sterility-testing methods in detecting low-level contamination in deliberately contaminated intravenous solutions was studied. One-liter bags of 5% dextrose (D5W) and 0.9% sodium chloride (saline injections were contaminated with Staphylococcus epidermidis and Pseudomonas aeruginosa; approximately 10(1) viable bacteria were injected into each bag. Two membrane-filtration methods (Ivex-2 and Addi-Chek) and one aliquot method [twice concentrated trypic soy broth (2X-TSB)] were used to test each of 10 diliberately contaminated solutions for both D5W and saline; 500 ml of each liter bag was filtered or added to 2X-TSB. Incubation containers were stored at 37 degrees C and inspected at 24, 48, and 72 hours for turbidity. There was no significant difference among the three methods in the detection of contaminated saline solutions. The Addi-Chek system was significantly less effective in detecting contamination in D5W than either of the other methods. It is concluded that the Ivex-2 system is accurate and the easiest-to-use system of the three tested.

Bacteriological Techniques↗

PubMed1995

Bacterial contamination of the water supply in newly installed dental units.

Bacterial contamination of the water supply of newly installed dental units was investigated. Water samples were collected from water supply lines to the dental operatories prior to connection of the dental units. Within hours following connection, and continuing for up to the 6 months of the study, water samples were obtained from the air-water syringe of the units. The samples were serially diluted 10-fold and plated on culture media for quantitative analysis. The formation of bacterial biofilm in the dental water supply tubing was monitored by scanning electron microscopy. The results of these studies revealed that the building's water supply to the dental units was contaminated prior to connection to the units. The water supply from the air-water syringe was therefore contaminated as well. The number of contaminant bacteria in the dental unit water supply increased for several weeks and then stabilized. The lumen of the dental tubing became progressively contaminated with bacterial biofilm, which subsequently became the primary reservoir for maintenance of the contamination of the dental unit water supply.

Bacteria↗

PubMed1994

[Grain contamination by deoxynivalenol in Russia].

Deoxynivalenol (DON) contamination of fresh harvested grain (570 samples of wheat and barley harvested in 1990-1992) and food grain crops (468 samples of wheat, rye, barley from different regions of the Russian Federation) was examined for frequency and degree. DON was detected in 70% of the fresh harvested wheat, exceeding MPC in 26% of the samples and in 67% of the stored barley samples, exceeding MTL in 14%. In 1992 100% of the harvested wheat from fusariosis natural habitat were contaminated exceeding MPC in 92%. Out of 314 samples of food wheat, 29% contained DON in quantities exceeding MTL in 14%. 11% of food barley and 8% of food rye samples contained DON within MTL. Maximum quantities of contaminated wheat were produced in the North-Caucasian regions (66% of the contaminated samples) or were imported (21%). Contaminated wheat was used most frequently in the North-Caucasian region and Central regions (56% and 30% of the contaminated samples, respectively).

Edible Grain↗

PubMed1994

Contamination of disinfection solution bottles used by contact lens wearers.

We investigated the contamination of disinfection solution bottles after 2 weeks of patient use. Forty-four subjects participated in the study and each used three soft lens care systems (cross-over study). The order in which the three care systems were dispensed was randomized to eliminate systematic bias. Sixteen subjects used only one of the systems (disinfection solutions) over three consecutive 2-week periods (reliability study). Contamination of the disinfection solution bottles occurred in 12 of the 180 bottles sampled (7%), and the level of contamination of these bottles ranged up to 10(5) colony forming units per milliliter. A wide range of microorganisms was identified in these positive samples, many of which were potential ocular pathogens. None of the subjects in the study (n = 60) showed contamination in more than one of the three solution bottles sampled, suggesting that the phenomenon was not strongly patient specific. The rate of contamination of disinfection solution bottles was not influenced by contact lens wearing experience (i.e., familiarity with care procedures), by the time of year (season) at which the samples were collected, or by the subjects' compliance with hand washing. However, among the 44 subjects in the cross-over study, the rate of contamination of disinfection solution bottles was influenced by the type of disinfection solution.

Bacteria↗