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OBJECTIVE: To estimate and compare contamination rates of three different urine-sampling methods in pregnant women to assess bacteriuria. METHODS: In this cross-sectional study, 113 pregnant women collected three different midstream urine samples consecutively: morning (first void); midstream (void without further instructions); and clean-catch sample (void after cleaning). The following end points were considered contaminants: epithelial cells, Gram-positive rods or mixed bacteria in the Gram stain, and mixed growth or skin flora in the urine culture. Intraindividual variability in contaminants was quantified with Fleiss-Cohen's weighted kappa statistic. Differences between samples were assessed using generalized estimating equations. RESULTS: Mainly low numbers of Gram-positive rods were more likely to be present in Gram stains of midstream samples compared with clean-catch samples (77.7% compared with 66.7%, P=.022). Morning samples showed more mixed growth compared with midstream samples (6.2% compared with 0.9%, P=.050). No consistency in quantity of contaminants was found in midstream samples compared with morning and clean-catch samples. No differences were found between the other end points in all three urine samples (P>.05). The study could detect an odds ratios of 2.0 for differences in urine-sampling methods with 80% power and 5% significance for most end points. CONCLUSION: In pregnant women, the contamination rate of midstream samples is comparable with the contamination rates of morning and clean-catch samples. The quantity of contaminants varied among the three samples collected by one woman. These results show that more complex, unpractical, and time-consuming morning and clean-catch samples are not superior. Therefore, we recommend a midstream sample to assess bacteriuria in pregnant women. (Obstet Gynecol 2013;121:299-305) DOI: http://10.1097/AOG.0b013e31827e8cfe

1853 packages of fresh chicken breast meat of German, Dutch and French origin were investigated for their contamination with Campylobacter and/or Salmonella. Swabs were taken and cultured from dripwater, meat surface, meat interior and packet bowl. Campylobacter was isolated from 619 meat samples (= 33%), Salmonella from 377 meat packages (= 20%). In 111 of these contaminated chicken samples, both Salmonella and Campylobacter were present. The contamination rate and the species spectrum observed differed depending on the origin of the packages and the time of control.

Summary A one year prospective study was conducted to determine the association between intravenous catheter contamination and increased dwell time, and to identify any related risk factors. Intravenous catheters obtained from 23 cats and 98 dogs in the Intensive Care Unit at the Ontario Veterinary College with dwell times > 72 hours for the test group (n=58) and < 72 hours for a corresponding control group (n=63) were cultured between April 1991 and March 1992. One hundred and twenty one catheters were cultured, 16 jugular, 99 cephalic, and 6 saphenous. The overall contamination rate was 13 out of 121 catheters cultured (10.7%); 9/63 (14.3%) control and 4/58 (6.9%) test catheters. The bacteria isolated were E.aerogenes, S.aureus (3), P.aeruginosa, P.multocida, and Bacillus sp (7). The Bacillus sp positive catheters (5 control and 2 test) were placed during a five day period, and contaminated gauze squares were identified as the source of infection in these catheters. After these were removed from the study, the group infection rate was 6.9% control and 3.6% test. There was no significant difference between groups and no associated risk factors were identified. We conclude that intravenous dwell time need not be restricted to

Using Chandra archive data we conduct a thorough survey of luminous X-ray sources. We directly analyze about 9400 ACIS Observations and cross-correlate the X-ray sources with 77,000 galaxies within 250 Mpc. The final catalog includes 119 unique luminous X-ray source candidates with from 93 galaxies or 41 HLX candidates with from 35 galaxies. We derive a moderate contamination rate due to foreground or background sources. We also cross-correlate the catalog with FIRST, perform variability and periodicity tests, and analyze one HLX candidate in particular. Our catalog could be a starting point to perform follow-up observations.

per bottle (post-intervention) (P＜0.0001). The rate of positive blood culture post-intervention (12.14%) was higher than that pre-intervention (6.65%) (P＜0.0001). The contamination rate post-intervention (1.82%) was also significantly greater than that pre-intervention (0.60%) (P＜0.0001). Except for anaerobes, there was no significant difference in the distribution of microorganisms between the pre- and post-intervention periods. The TTP for anaerobe bottles post-intervention was significantly shorter than that of pre-intervention (16.1±16.3 versus 18.6±18.3 h). Conclusion: This study suggests that continuing education about adequate blood volume and aseptic techniques is needed to increase the rate of positive blood cultures and reduce the contamination rate of blood cultures. (Ann Clin Microbiol 2016;19:70-76)

Contamination of blood samples is a pressing clinical issue for nursing and medical staff involved in obtaining such samples. Contamination of blood samples can lead to false positive results and therefore could potentially have a deleterious impact on clinical decision-making through interpreting an erroneous result. A simple intervention to reduce the incidence of blood sample contamination using a blood culture kit was investigated. One hundred blood samples were collected from patients using either the standard blood sampling protocol (N=50) or a new blood culture kit (N=50). The use of the blood culture kit was associated with a significant reduction of blood sample contamination. Implications for clinical practice are discussed and the direction of future research indicated.

BACKGROUND AND OBJECTIVE: Blood culture contamination in the pediatric population remains a significant quality and safety issue because false-positive blood cultures lead to unnecessary use of resources and testing. In addition, few studies describe interventions to reduce peripheral blood culture contamination rates in this population. We hypothesized that the introduction of a standardized sterile collection process would reduce the pediatric emergency department’s peripheral blood culture contamination rate and unnecessary use of resources. METHODS: A sterile blood culture collection process was designed by analyzing current practice and identifying areas in which sterile technique could be introduced. To spread the new technique, a web-based educational model was developed and disseminated. Subsequently, all nursing staff members were expected to perform peripheral blood cultures by using the modified sterile technique. RESULTS: The peripheral blood culture contamination rate was reduced from 3.9% during the baseline period to 1.6% during the intervention period (P < .0001), with yearly estimated savings of ∼$250 000 in hospital charges. CONCLUSIONS: Subsequent to our intervention, there was a significant reduction of the peripheral blood culture contamination rate as well as considerable cost savings to the institution. When performed in a standardized fashion by using sterile technique, blood culture collection with low contamination rates can be performed via the insertion of an intravenous catheter.

The consumption of foodborne pathogens contaminated in food is one of the major causes of diarrheal diseases in Thailand. The objective of this study was to evaluate the prevalence and types of contaminating bacteria in retailed foodstuffs in Thailand. Food from four categories (137 samples total), including meat (51 samples), vegetables (38 samples), fish or seafood (37 samples), and fermented food (11 samples), was purchased randomly from seven different open-markets and seven supermarkets in Thailand from August 2010 to March 2011. Seven types of major foodborne pathogens were identified using conventional culture methods. Approximately 80% of meat samples tested was contaminated with Salmonella spp. In contrast, the Salmonella spp. contamination rate of vegetable (5%) or fermented food (9%) samples was comparatively low. Six strains of Cronobacter sakazakii and two strains of Yersinia enterocolitica were also isolated. A substantially higher rate of contamination by Bacillus cereus was observed in fermented food (82%) than in samples of meat (2%) and fish or seafood (5%). Seven Listeria spp. isolates were obtained from meat and fish or seafood samples. Approximately 39% of samples tested were found to be contaminated with Staphylococcus spp. (54 isolates). The rate of bacterial contamination of meat did not depend on the type of market. However, the contamination rate of Staphylococcus spp. in vegetables was higher in open markets than in supermarkets, and the contamination rate of Salmonella spp. and Staphylococcus spp. in fish or seafood samples purchased in open markets was likewise higher than in those purchased in supermarkets. Therefore, improvement of hygienic practices throughout the food chain may be required to reduce the risk of food poisoning.

BACKGROUND Healthcare workers' mobile phones are easily contaminated with pathogenic bacteria and could be vehicles of transmission. Smart phones are increasingly used in the hospital. The objective of this study was to compare the contamination rate of bacteria with pathogenic potential between smart phones and non-smart phones. METHODS We screened mobile phones of healthcare workers in three teaching hospitals in South Korea. The identification of cultivated micro-organisms and assessment of antibiotic susceptibility were performed. RESULTS One hundred fifteen (56.7%) participants used smart phones, and 88 (43.3%) used non-smart phones. Bacteria with pathogenic potential were isolated from 58 (28.6%) mobile phones, more often from smart phones than from non-smart phones (34.8% vs 20.5%, P=0.03). Multivariate analysis including various characteristics to determine risk factors revealed that only smart phones (vs non-smart phones) were a significant risk factor for contamination by bacteria with pathogenic potential (adjusted odds ratio [OR], 4.02; 95% confidence interval [CI], 1.43-11.31). Also, in a multivariate model including phone size, the smart phone was still a significant risk factor for the pathogen contamination (OR, 4.17; 95% CI, 1.07-16.33; P=0.04). CONCLUSION The smart phones of healthcare workers were contaminated with bacteria with pathogenic potential to a greater extent than were non-smart phones. Journal of Hospital Medicine 2013;8:144–147. © 2013 Society of Hospital Medicine

A cross-sectional study was conducted from October, 2009 to March, 2010 to assess the level of contamination of informally marketed milk with Staphylococcus aureus at farms and milk collection centers in Debre-Zeit, Ethiopia. One hundred and seventy raw farm bulk milk samples, 25 mixed bulk milk samples and 20 pasteurized and packaged milk samples were collected from 14 milk collection centers and isolation and identification ofS. aureus were carried out following standard method. S. aureus was isolated from 44% of farm bulk milk and 72% of milk collection centers’ bulk milk and it was not detected from pasteurized milk samples. Contamination rates of farm bulk milk with S. aureus were significantly different among the collection centers (c2 = 31.8, df = 13, p = 0.003). The milk produced and collected in peri-urban areas was significantly more contaminated with S. aureus (64%) than milk produced and collected in urban areas (38%) (c2 = 7.18, df = 1, p= 0.007). The frequency of isolation of S. aureus in milk collection centers bulk milk varied between 67 and 100% among collection centers. However, the contamination rates were not significantly different among these collection centers (c2 = 1.5, df = 4, p = 0.83). The overall contamination rate at collection centers (72%) was significantly higher than that at the farm level (33%, c2 = 10.6, df = 1, p = 0.001). Overall, the study revealed that milk produced and collected in and around Debre-Zeit was found to be contaminated with S. aureus, raising the issue of quality control and improving the safety of milk to safeguard the consumer from associated health problems and enabling the producers to earn much more from milk sale. Key words: Bulk milk, collection centers, Debre-Zeit, Ethiopia, Staphylococcus aureus.

Dr. Nelson has no financial or proprietary interest in the materials presented herein. doi: 10.3928/01913913-20120523-01 The incidence of perioperative inflammation after strabismus surgery is uncommon. Many of these cases may be related to when there is prolongation of the suture material dissolving, creating conjunctival injection around the suture. This phenomenon is more common in adult strabismus surgery patients. The incidence of endophthalmitis after strabismus surgery is extremely rare; in this issue, Eustis and Rhodes estimate it as 1 in 35,000 to 1 in 185,000 cases following strabismus surgery. These authors noted that in a prospective randomized analysis that the contamination rate of suture material use in strabismus surgery was least when the suture was pre-soaked with antiseptic and antibiotic/steroid combination compared to sutures without pretreatment or soaked just with antibiotic/steroid combination. Unfortunately, the authors did not identify the pathogen contaminating the sutures. Many of the pathogens were most likely normal flora. Because the incidence of endophthalmitis following strabismus surgery is rare and no specific pathogens were identified in Eustis and Rhodes’ study, further prospective studies may help to determine whether presoaking sutures prior to strabismus surgery are appropriate.

Objectives: To study the potential of buffy coat culture as a diagnostic tool for neonatal late-onset sepsis. Methods: This was a study of diagnostic accuracy in newborn infants born at 28-41 weeks of gestation, weighing >800. g, with ≥8 points on the NOSEP-1 scale. Paired samples for total blood culture (TBC) and buffy coat culture were drawn. We established the positivity rate, sensitivity, specificity, predictive values, and likelihood ratios, and compared time to positivity and contamination rates. Results: Fifty-two newborns were included in the study. Twenty-one TBC and 22 buffy coat cultures were positive. The positivity rate for TBC was 40.4% and for buffy coat culture was 42.3% (p=. not significant). Three TBC were positive with negative buffy coat culture. Four buffy coat cultures were positive with negative TBC; Kappa agreement was 0.723, p

Fifty three samples of four varieties of maize were obtained from 18 storage facilities in Zaria and its environs, all within Kaduna State, Nigeria and plated directly on potato dextrose agar (PDA). Samples which yielded Fusarium species were further tested for the presence of toxins. Seven samples yielded fumonisins alone, while both fumonisins and deoxynivalenol (DON) were found in three samples corresponding to 18.87% toxin contamination rate. Fusarium verticilloides was found to be the most toxigenic species occurring in eight toxin-contaminated samples while Fusarium proliferatum occurred only once. Three samples had fumonisin content above the 5 ppm threshold value while the other samples did not exceed the 1 ppm upper limit for DON. Fusarium contamination of grains used in industrial productions exists and thus there is the need for regulations guiding the storage and industrial utilisation of maize to minimize the risk of mycotoxicoses in humans and animals. Key words: Fumonisins, deoxynivalenol, stored maize, Fusarium, Zaria, mycotoxin, contamination, industrial productions

Surgical site infection remains a concern in orthopedic surgery, and contamination of C-arm covers is a potentially modifiable risk factor.A single-cohort study was conducted using 30 consecutive patients undergoing operative fracture fixation. Cultures were obtained from the C-arm cover after initial draping and every 20 min thereafter. The total number of persons in the operating room (person-hours/h of study time) and the number of door openings were recorded. The C-arm position changes and the time to contamination were monitored.The median time from the start of the operation to contamination was 20 min. There was a 17% contamination rate on initial draping, 50% at 20 min, 57% at 40 min, and 80% by 80 min. The C-arms in five cases were not contaminated during the surgery. Time to contamination correlated significantly with lateral position changes (correlation [r]=0.64; p=0.003) but was not related to C-arm position changes (r=0.22; p=0.34), number of door openings (r=0.20; p=0.39), or person-hours/h (r=0.04; p=0.85).Contamination of the C-arm drape occurs often and early during surgery for orthopedic fractures. We recommend minimal contact with the C-arm to avoid contamination of the surgical field.

A total of 360 samples including fresh fecal droppings, neck skins, and swab samples was collected from 24 broiler flocks and processed by 12 modern processing plants in 6 states in Malaysia. Ninety samples from 10 traditional wet markets located in the same states as modern processing plants were also collected. Microbiological isolation for Campylobacter was performed following ISO 10272-1:2006 (E). The overall rate of contamination for Campylobacter in modern processing plants and in traditional wet markets was 61.1% (220/360) and 85.6% (77/90), respectively. Campylobacter jejuni was detected as the majority with approximately 70% for both facilities. In the modern processing plants, the contamination rate for Campylobacter gradually declined from 80.6% before the inside-outside washing to 62.5% after inside-outside washing and to 38.9% after the post chilling step. The contamination rate for Campylobacter from processed chicken neck skin in traditional wet markets (93.3%) was significantly (P

Summary In this prospective study we analysed 336 consecutive central venous catheters in neonates less than 3500 g. A protocol standardizing the technique of insertion, the care of the catheter, the preparation of solutions and weekly bacteriological screening was applied to all catheter insertions. Mechanical complications were observed in 15 (6%), catheter dislodgement (5%), obstruction (8%), perforation (2%) and caval vein thrombosis (0.6%). Routine bacteriological cultures of feeding solutions and infusion devices showed a contamination rate of 3.5% and 2%. Skin swab and catheter tip cultures after catheter removal demonstrated positive results in 6% and 4.7%, but catheter related sepsis occurred in only 2.3%. Staphylococcus epidermidis was found in 81% of all positive bacterial cultures. Four point seven per cent of catheters were removed for suspected infection though only one third of them produced a bacteriological growth. We conclude that the risk of mechanical complications and contamination of central venous catheters in neonates can be minimized by the use of a standardized protocol.

In a prospective controlled trial we compared the rates of intraluminal contamination between the two lumens of a double-lumen central venous catheter. One lumen was used for repeat infusions and injections, and the other was permanently connected to a slow infusion of 0·9% NaCl. The study was designed so that the patient was his own control. Twenty-eight catheters were examined and comparison with catheter-tip cultures was performed in 24. Intraluminal culture was performed 67–77 h after insertion of the catheter and catheter-tip culture was performed on removal of the catheter. The contamination rate from catheter-tips was 20·8%, which is acceptable compared with other studies. There was only one positive intraluminal culture in each group (3·6%), and thus no correlation was found between contamination rate and the number of times the infusion-line had been interrupted for use. As for catheter-tip contamination, we found no correlation between infusion of blood-products or parenteral nutrition and contamination rates.

The persistence of accidentally introduced bacterial contaminants inDelphinium tissue cultures can be prevented by acidification of the tissue culture medium. Using this preservation method the contamination rate ofDelphinium cultures could be reduced by more than 50%.

blood culture contamination rate. JAMA 269: 1004-I 006. Weinstein, M.P. 1996. Current blood culture methods and systems: clinical concepts, technology. and interpretation of results. Clin. Infect. Dis. 23:40-46. Aronson, M.D. and D.H. Bor. 1987. Blood cultures. Ann. intern. Med. IO6:246-253. Bryant, J.K. and CL. Strand. 1987. Reliability of blood cultures collected from intravascular catheter versus venipuncture. Am J. Clin. Pathol. 88: 113-l 16. IS. IO. Tonnesen. A.. M. Peuler, and W.R. Lockwood. 1976. Cultures of blood drawn by catheters vs. venipuncture. JAMA 235: 1877. I I. Felices, F.J. et al. 1979. Use of the central venous pressure catheter to obtain blood cultures. Crit. Care Med. 7:78-79. 16.

Objective Blood culture contamination rates (CRs) in emergency departments (EDs) vary from 1% to 9% in previous studies. High CRs cause unnecessary admissions, antibiotics, and costs. Different measures have been tried to improve CR. This study sought to determine the ED CR at Arkansas Children's Hospital (ACH) and evaluate an educational intervention. Design A slide presentation of the ACH's blood culture collection procedure was made. The ED nursing staff viewed this individually and demonstrated the procedure on a mock extremity. Data before (from June 1 to November 30, 2007; PRE) and after (from February 1 to July 31, 2008; POST) intervention regarding blood cultures positive for organism submitted to the ED and any descriptive data were collected retrospectively. Descriptive statistics described the CR, positivity rate (PSR), and pathogen rate (PR). Frequent collectors were identified as those submitting more than 72 blood cultures during PRE and during POST. Contamination rate in frequent collectors was independently assessed for improvement. This study was approved by the institutional review board of the University of Arkansas for Medical Sciences. Results Positivity rate during PRE was 6.8% (n = 15; 95% confidence interval [CI], 2.9-10.7); 114 were contaminants (CR, 5.0%; 95% CI, 1.04-8.98) and 40 were pathogens (PR, 1.8%; 95% CI, ± 4.28). Positivity rate during POST was 6.3% (n = 157; 95% CI, 2.6-10.0); 124 were contaminants (CR, 4.9%; 95% CI, 1.14-8.66) and 33 were pathogens (PR, 1.4%; 95% CI, ± 4.22). For both PRE and POST, contaminants represented 74% or greater of all the positives and more than 75% of contaminants occurred in patients 0 to 36 months old.Contamination rates of individual practitioners ranged from 0% to 17% (PRE) and from 0% to 21% (POST). The CR was lower in POST for samples submitted from frequent collectors (practitioners submitting >72 blood cultures per study period, n = 6), was evaluated separately, and found to improve in POST (from 4.1% to 2.7%). A t test for matched samples for these samplers revealed a significant decrease in the POST period, P = 0.03. Conclusions The CR in the ACH ED for peripherally drawn blood cultures is approximately 5% monthly with less than 2% PR. For each culture positive for organism, the chance of contamination is 75% or higher. An intervention emphasizing the appropriate technique, monitored training, and improved CR of a group of frequent collectors is warranted.

Our hospital’s blood culture contamination rate within adult wards reached 5.2% prior to the introduction of adult blood culture packs. In addition, during 2009 the hospital’s blood culture collection rate was 31 blood culture bottles per 1000 patient days. The aim of the study was to assess the impact of introducing a blood culture collection pack on the rate of blood culture collection and contamination.

At the Institute, blood cultures are drawn by doctors. Since 2009, more than 5% of blood cultures grew organisms as contaminant and was a concern to the Infection Control Committee. Our target is to reduce to 3% to meet the standard set by the American Society of Microbiology. The objectives of the clinical education are to enforce best practices in blood culture collection and to use 2% chlorhexidine as a skin decontaminant.

Syringes used to administer intravenous medications in an intensive care unit were cultured, and the isolates were compared with those from positive blood cultures from the same patients. The overall contamination rate was 16%, and syringes used for drugs such as insulin, which support bacterial growth, had higher contamination rates. All syringes should be changed routinely after 6h.

The purpose of this study was to establish a technique for collecting semen from blue-fronted Amazon parrots (Amazona aestiva aestiva) and to evaluate the samples that were collected. The massage method is the most common technique used to collect semen in birds and has been proven successful in several psittacine species; however, collection attempts in larger parrots have been unsatisfactory. Six blue-fronted Amazon parrot males, 3 paired with hens and 3 unpaired, were used in this study. The semen collection technique was revised to allow collection from individual birds by a single person. Semen collection was attempted from the 6 parrots on 52-56 occasions, which totaled 330 single attempts. Nineteen ejaculates were collected, and each bird produced at least 1 ejaculate that contained spermatozoa. Large ranges of sample volume (1-15.4 microL), sperm quality (motility = 2%-60%; live:dead ratio = 2:198 to 185:15), sperm concentration (0.79-3.3 x 10(6) sperm/mL), and contamination rate (0%-100%) were observed. Measured parameters did not appear to be significantly impacted by birds being paired or kept singly. Because of the relatively short acclimation period, the birds appeared to be sexually inactive for the majority of the study. Further research using sexually active birds will be necessary to determine standard spermatological parameters and verify the success of the methodology used here.

OBJETIVO: avaliar a contaminação bacteriana presente na ponta ativa de alicates ortodônticos utilizados no meio acadêmico. MÉTODOS: selecionou-se 34 alicates, 17 do modelo 347 e 17 do modelo 139. O grupo controle foi composto por 3 alicates de cada modelo, previamente autoclavados. Os alicates do grupo experimental, após o uso, foram imersos em 10ml do meio de cultura líquido Brain-Heart Infusion (BHI) por 2 minutos, seguido de cultivo a 37°C (24 a 48h) e semeadura (duplicata) em diferentes meios de cultura sólidos à base de ágar, para detecção e identificação de agentes microbianos. RESULTADOS: as análises microbiológicas revelaram contaminação em ambos os tipos de alicates ortodônticos. Observaram-se variadas formas bacterianas, predominando estafilococos e cocos isolados gram-positivos. Os alicates removedores de anéis apresentaram maiores índices de contaminação, com médias entre 2,83 x 10(9) e 6,25 x 10(9) UFC/ml, variando de acordo com o tipo de meio de cultura. Os alicates 139 também continham bactérias da microbiota bucal, com variações entre 1,33 x 10(8) e 6,93 x 10(9) UFC/ml, sendo que a maior média obtida refere-se ao meio de cultura próprio para desenvolvimento de estafilococos, indicando, em certos casos, presença da espécie Staphylococcus aureus, microrganismos que não fazem parte da microbiota bucal normal, sendo comumente encontrados na cavidade nasal e superfícies epiteliais das mãos. CONCLUSÃO: constatou-se que os alicates ortodônticos apresentam-se contaminados, como qualquer outro instrumental odontológico, após serem empregados em atendimentos clínicos. Em razão disso, há necessidade de submetê-los previamente aos procedimentos de esterilização após cada utilização em pacientes.

SUMMARY: Requirements for bacterial testing of blood components on a defined quantity as part of routine quality control were introduced in Germany by the National Advisory Committee Blood of the German Federal Ministry of Health in 1997. The philosophy was to establish standardized methods for bacterial testing. Numerous measures to reduce the risk of bacterial contamination were implemented into the blood donation and manufacturing processes between 1999 and 2002. German Blood establishments performed culture-based bacterial testing on random samples of platelet concentrates (PCs), red blood cells (RBCs) and fresh frozen plasma (FFP) and reported data out of the production periods 1998, 2001 and 2005/2006. While the bacterial contamination rate of apheresis PCs remained nearly unchanged, it decreased by 70% for pooled PCs to a rate of 0.158% in the last observation period. Leukocyte-depleted RBCs with diversion of the initial blood volume showed a contamination rate of 0.029% which is significantly lower than that of RBCs without leukocyte depletion and diversion (0.157%). The contamination rate of plasma decreased by 80%. Preventive measures resulted in a significant reduction of bacterial contamination of blood components. Long-term monitoring with standardized methods for bacteria testing supports evaluation of the cumulative effect of contamination reducing measures.

EUV lithography is the most promising new technology for the next node of semiconductor devices. Unfortunately, the high energy photons are likely to generate more contamination than observed with ArF or KrF light which can reduce the transmission of the EUV optics. Resist outgassing is considered to be an important contamination source, however, not enough is known about the way a resist composition influences the contamination growth rate, while this information is crucial to guide the development of EUV resists. To reduce the knowledge gap, FUJIFILM and imec started a joint effort aimed at systematically exploring the contribution of the different resist components and at understanding the effect of chemical modifications of the different components on the contamination tendency of resists. The project focuses on (1) the identification and quantification of the outgassing components from resist by RGA measurements, (2) on the quantification of the resist related contamination rate by witness sample (WS) testing, and (3) on the correlation between these two results knowing the details of the resist chemistry. To explore the effect of the resist composition upon contamination growth, the following approach was followed. The focus was put on chemically amplified resists (CAR), since this chemistry is mostly used in EUV lithography. Both PAG blended as well as PAG bound systems were explored, and the following resist components are individually varied: polymer matrix, blocking groups, PAG type and concentration. In this way the total contamination of a resist can be divided into the separate contributions of the different resist components upon the contamination growth rate, which is a huge step forward in the understanding of optics contamination due to resist.

Peer-reviewed journal article, Applied Rheology

We evaluated the performance of MGIT 960 system in terms of recover rate, detection time of mycobacteria and contamination rate from various human clinical specimens and compared it with already in use BACTEC 460 TB system and conventional LJ medium. This is the first reported study on MGIT 960 and its comparison with BACTEC 460 system in Pakistan. A total of 260 different clinical specimens received for the culture of mycobacteria were dealt during the six months study period. All the specimens were digested and decontaminated according to the standard N-acetyl-Lcysteine NaOH method. All the processed specimens were inoculated on both the liquid systems and solid medium and incubated for six weeks and eight weeks consecutively. A total of 44 mycobacterial isolates (Mycobacterium tuberculosis, n=43; Mycobacteria other than tuberculosis, n=1) were recovered from 260 clinical specimens. The recovery rate of M. tuberculosis complex was 97.6% on BACTEC MGIT 960 system and 93.0% on BACTEC 460 system and 83.7% on LJ medium. The mean detection time of mycobacteria on BACTEC MGIT 960 system was 11.2 days in smear positive cases, 14.2 days in smear negative cases and 14.8 days in smear positive cases on BACTEC 460 system. Contamination rates were 9.6% and 5.6% and 3.4% for BACTEC MGIT 960, BACTEC 460 system and LJ medium respectively. The non-radiometric, fully automated BACTEC MGIT 960 system has better diagnostic ability as compared with radiometric, semi-automated BACTEC 460 system and LJ medium, so it can be used as a reliable alternative in over burden laboratories.

Cabin surfaces of ambulance cars transporting hospitalised patients are at risk of meticillin-resistant Staphylococcus aureus (MRSA) contamination. In this study ambulance cars were analysed for the presence of MRSA immediately after transport of MRSA-colonised or -infected patients (two sites at the stretcher, three sites at the interior walls). Eighty-nine of 100 transport events, which fulfilled the inclusion criterion of transport time less than 20 min, were further analysed. Eight ambulance cars (9%) were contaminated (90% confidence interval: 4-14%). Transport time of 11-20 min did not result in a higher contamination rate than shorter transport time of 1-10 min. MRSA was detected only on the stretcher, i.e. the headrest and the handles. Cabin walls were not contaminated. In conclusion, ambulance cars were contaminated with MRSA even at short transport times. Disinfection after short-term transport of MRSA-positive patients should be restricted to surfaces in close vicinity to the patient's position. Consecutive investigation of 60 transport events in the absence of MRSA notification did not reveal any MRSA, but meticillin-susceptible S. aureus was detected in 12 cars, predominantly at handles and headrests. This finding highlights the importance of disinfection of surfaces in the vicinity of patients irrespective of the MRSA status.

Blood culture is a vital investigation and can be the first step in obtaining a definitive diagnosis in a patient with presumed sepsis, but can also have serious adverse consequences for the patient. The aim of this study was to evaluate the extent of the blood culture contamination problem at the Lancashire Teaching Hospitals (LTH) and to assess the impact of the introduction of a new blood culture collection kit on the contamination rate. Blood culture contamination rate at the LTH before the introduction of the blood culture collection kit was 9.2%. A fall in contamination rate was observed after kit introduction, to 3.8%, a proportion approaching the American Society of Microbiologists' recommended standard of ≤3%. The reduction in contamination was associated with an unintended, yet sustained, reduction in the total number of blood culture sets collected and an unwanted reduction in the number of genuine Gram-negative bacteraemias. This reduction may reflect education and training issues at the time of the introduction. In the era of 'route cause analyses', it may also reflect fears by junior colleagues of the consequences of being found responsible for a blood culture contaminant. The study recommended continuing with the blood culture kit, but ensuring regular training and education sessions, carried out in a non-blame manner.

Diagnosis of urinary tract infection (UTI) is primarily done by microbiologic culture, which is time-consuming and can produce false-positives and false-negatives. Flow cytometry allows for rapid screening of many samples and eliminates culturing. We analyzed the Sysmex UF-1000i (TOA Medical Electronics, Kobe, Japan) for accuracy in identifying RBCs and WBCs, casts, bacteria, and epithelia. We also evaluated its precision, linear estimation of results, carryover contamination rate, and anti-interference. UF-1000i agreement with manual counting was approximately 95% for RBCs and WBCs, epithelia, and casts. Its coefficient of variation for bacteria ranged from 4.7% to 15.2%. UF-1000i screening for UTIs exhibited great sensitivity (97%), specificity (79%), positive predictive value (70%), negative predictive value (99%), and accuracy (85%). The negative predictive value remained high even with complex UTI samples. The Sysmex UF-1000i shows great promise in excluding more than 50% of true-negative samples, improving detection efficiency, and reducing laboratory costs.

Background Gloves are a necessary contact precaution to prevent transmission of infectious pathogens that spread by direct or indirect contact with an infected person or a contaminated environment. This article reports a study investigating hand and environmental contamination levels when health care workers (HCWs) followed two different methods of removing gloves at two distances from the rubbish bin. Methods Fifty HCWs performed a personal or causal glove removal method (pretest) and a Centers for Disease Control (CDC)-recommended glove removal method (posttest) at distances of 2 feet and 3 feet from the rubbish bin after the application of fluorescent solution (the simulated contaminant) onto their gloved hands. Results The incidence of the small patch of fluorescent stain ( 2 ) on the front of the doffed gloves was significantly lower in the posttest than in the pretest. The incidence of small and large patches (>1 cm 2 ) on the front of the doffed gloves and on the cover of the rubbish bin was significantly lower at 3 feet than at 2 feet. Health care assistants had significantly higher levels of contamination than other HCWs in the pretest but not in the posttest. There was no significant difference in hand contamination rate between pretest and posttest based on distance from the rubbish bin and type of HCW. Conclusion The impact of the glove removal procedure and the distance to the bin in which used gloves are discarded should be taken into consideration on a daily basis, along with the supervision of infection control measures by minor staff.

Two similar trials were conducted to evaluate the effects of bird density on Salmonella contamination of processed broilers. Commercial strain broiler chicks were reared in floor pens on new litter at densities of 557, 619, 697, 796, 929, and 1,115 cm2 per bird. Twenty percent of the chicks in each density were gavaged directly into the crop with .5 mL of 108 nalidixic-acid-resistant (NAR) Salmonella typhimurium on Day 2. Twenty percent of the uninoculated birds in each density category were processed at 42 days. Prechill carcasses were evaluated for NAR Salmonella incidence using the whole carcass rinse technique and a mechanical shaking device. The resulting NAR Salmonella contamination rates (from lowest to highest bird densities) were as follows: 55, 4.2, 35.7, 34.3, 88.9, and 20% in Trial 1; and 30, 20.8, 28.6, 50, 58.3, and 30% in Trial 2. A random sample of the prechill carcasses of gavaged birds indicated a contamination rate of 13.8% in Trial 1 and 61.1% in Trial 2. The NAR Salmonella contamination rates of the prechill carcasses did not appear to be affected by the bird densities evaluated in these trials. Feed intake and body weight at 42 days were adversely affected by the highest bird density, but feed utilization was not affected.

We studied the effect of the procurement team on the risk of contamination in 270 large bone allografts retrieved from 53 non-living donors under strictly aseptic conditions.The overall contamination rate was 8.1%. When the procurement team was constituted by three or less members the contamination rate was 5.6%, while if there were four or more members the rate was 12.9%; this difference was significant in the statistical analysis.We conclude that a procurement team constituted by three or less trained members is a determinant factor in decreasing the bacterial contamination rate of bone allografts.

Purpose To determine the rates of microbial contamination of solutions and lens accessories of existing ortho-k lens wearers and the effect on contamination rates of monthly replacement and warnings. To investigate self-reported levels of compliance with care of the lenses and lens accessories and correlation of these levels with the rates of microbial contamination. Methods Asymptomatic ortho-k lens wearers with at least 6-month successful use were requested to bring their lenses, solutions, and accessories to their next aftercare visit. All items, except the lenses, were replaced at each data collection visit. Samples collected from the lens surface, solution, and accessories were cultured for pathogens. These procedures were repeated twice at 1-month intervals. At the first visit, each subject and/or parent was interviewed about the care/use of the lens and accessories. Results Thirty-eight subjects completed the study. Initial contamination rates of the lenses, lens cases, and tweezers were 29, 34, and 46%, respectively. Rates of contamination dropped for lenses, suction holders, and tweezers during the three-visit intervention. Contact lens solutions, except lens cleaner were contaminated on all occasions with the most contaminated product being artificial tears [33% (n = 18)]. There was no improvement in the contamination rate of the lens cases. The most common pathogens isolated were Staphylococcus aureus and Serratia marcescens. Compliance was lowest for care of lens cases and highest for care of lenses. However, correlation between reported compliance and presence of pathogens failed to reach significance. Conclusions Subjects' awareness of the importance of lens cleanliness is high and can be improved by regular reinforcements. However, attitudes toward cleaning of accessories was far less satisfactory and while replacement and warnings resulted in significant improvements of contamination rates of tweezers and suction holders, more emphasis should be placed on educating patients on correct care of lens accessories.

Background Nosocomial bacteremia caused by the contamination of intravenous (IV) infusates is considered rare. Unfortunately, this problem has been underestimated because its identification requires culturing infusates, a procedure not performed routinely. Methods This study was conducted in a referral hospital where IV infusates are admixed in nursing areas. The aim was to determine the prevalence of infusate contamination in adult patients with gram-negative rod (GNR) bacteremia. Over a period of 32 months, a specimen of infusate was drawn for culture from each patient recruited after the laboratory reported a GNR in the blood. Results A total of 384 infusates were cultured from 384 patients who had been diagnosed with GNR bacteremia. Seven infusates grew a GNR in culture, for a contamination rate of 2% (7/384; 95% confidence interval [CI] = 1% to 3%). In all cases, the infectious organism was the same as the organism isolated from the blood. Infusate contamination was responsible for 7% (7/108; 95% CI = 2% to 11%) of all primary bloodstream infections and 11% (7/62; 95% CI=2% to 22%) of all primary bloodstream infections not associated with central venous catheter infection. Conclusions For patients in hospitals where IV drugs are admixed in nursing units, we recommend instituting infusate culture as routine practice following the diagnosis of a GNR in the blood.

Cetylpyridinium chloride (CPC), sodium hydroxide (NaOH) and formaldehyde (HCHO) were compared for their efficacy as decontamination substances for the isolation of mycobacteria from drinking water samples. For this purpose pure cultures of nine mycobacterial strains and four strains of potential contaminants were tested for their sensitivity to CPC (0.001, 0.003, 0.005%), NaOH (0.5, 1.0%) and HCHO (0.1, 0.5, 1.0%). The results of these tests are given in terms of decimal reduction times. Additionally, 36 drinking water samples were processed using the following six decontamination methods: (i) CPC, 0.001%, 30 min; (ii) CPC, 0.005%, 30 min; (iii) NaOH, 0.5%, 30 min; (iv) NaOH, 1.0%, 30 min; (v) HCHO, 0.1%, 60 min; (vi) HCHO, 0.5%, 60 min. In this field study method ii proved to be the most effective procedure resulting in the highest isolation (64%) and lowest contamination rate (11%). Method iii may be useful when testing water samples for Mycobacterium chelonae and M. fortuitum and if high concentrations of red pigmented contaminants resistant to CPC are to be expeected. Methods v and vi were not found to be suitable for decontamination.

The bacterial contamination rate of contact lens cases in different care systems was investigated and a comparison was made between the case caps and the case wells. Contact lens cases were collected from 39 hydrogen peroxide care system users and 14 non-hydrogen peroxide care system users at the Southern California College of Optometry during routine follow-up care. The total contamination rate of all the case samples was found to be 19% (10/53). Fifteen percent of the cap samples (8/53) and 19% of the well samples (10/53) were found to be contaminated. Of the samples that were contaminated, 80% (8/10) were found to be contaminated in both the cap and the well and 80% were found to be positive for the Pseudomonas aeruginosa strain of bacteria. There was no difference in contamination rate between hydrogen peroxide and non-hydrogen peroxide disinfecting systems. These results indicate a lower incidence of lens case contamination than in previous investigations, but emphasize the need for regular cleaning or disinfecting of the entire contact lens case as part of routine care by contact lens patients.

Pathogenic Yersinia enterocolitica strains (serogroups 0:3;0:9 and 0:5.27) were isolated from 36 (42%) of 86 porcine tonsils, 8 (20%) of 40 tongues, 17 (17%) of 100 rectal swabs and from 4 (1%) of 400 pork samples. Pathogenic Yersinia strains were not isolated from samples of 210 pig carcasses and from 20 samples of porcine head meat. These results confirm that pigs are an important reservoir of pathogenic Y. enterocolitica. However, contamination of carcasses during the slaughtering process with Yersinia from either faecal material or from the tonsillary region does not seem to occur frequently and this may also explain the low contamination rate of pathogenic Y. enterocolitica found for pork. For the isolation of pathogenic Y. enterocolitica strains from foods, enrichment in irgasan-ticarcillin-chlorate broth (ITC) and isolation on SS-deoxycholate-calcium agar (SSDC) is recommended.

Background: Bacterial contamination of enteral feeding solutions has been associated with a variety of infectious complications. In order to minimize contamination of enteral feeding solutions, it is recommended that their infusion times be limited. This leads to wasted product and inefficient use of personnel time. The contamination rate for sterile, non-air-dependent, closed system enteral feeding solutions and the length of time over which they can be safely infused in immunocompromised patients is not known. Methods: Enteral feeding was administered to 15 liver transplant recipients via a sterile, closed, non-airdependent system. At the conclusion of infusion of each bag of enteral feeding solution, the residual solution was quantitatively cultured. Subjects were also monitored for infectious complications. Results: The mean infusion time per 1.5-L bag of enteral feeding solution was 22.7 hours (range 10 hours to 35 hours). None of the 52 samples harbored bacteria. No subject developed a nosocomial in...

Bacterial blight of onion is a severe disease, which emerged over the past decade in several onion-producing areas. This disease currently is observed in both the Old and New Worlds. Although the causative agent, Xanthomonas axonopodis pv. allii, is potentially seedborne, seed transmission and significance of seedborne initial inoculum for the development of bacterial blight of onion previously has not been assessed. This article describes experimental work designed to evaluate the biological importance of seedborne X. axonopodis pv. allii as an initial inoculum source, and examine the temporal and spatial dynamics of the disease. Over 3 years, outbreaks of bacterial blight of onion always were induced in experimental plots sown with naturally contaminated seed lots, with a contamination rate determined as 0.04%. Analyses of disease patterns indicated a likely seedborne origin for the inoculum associated with the early stages of epidemics. Spatial analyses performed with several statistical methods indicated aggregated patterns of disease incidence data. Primary foci enlarged over time, and a few distinct secondary foci sometimes were established after occurrence of wind-driven rains (with gusts up to 15 m s-1). Distances between primary and secondary foci ranged from less than 1 m (satellite foci) to 25 m. It remains possible that longdistance dispersal of inoculum was at least partly involved in the later stages of epidemics.

Sixty samples of tissue fragments with lesions suggestive of tuberculosis from bovine abattoirs, kept in saturated solution of sodium borate, were subjected to four treatments: 4% NaOH (Petroff Method), 12 % H2SO4 and 1.5% HPC (1-Hexadecylpyridinium Chloride) decontamination, and physiological saline solution (control). The HPC method showed the lowest contamination rate (3%) when compared to control (88%, p

Background: The BACTEC MGIT 960 was evaluated and compared with BACTEC 9000 MB and Lowenstein-Jensen medium for recovery rate of mycobacteria, time to detection, and contamination rate. Methodology: 147 sputum samples obtained from patients with suspicion of tuberculosis were processed and inoculated into BACTEC MGIT 960, BACTEC 9000 MB and Lowenstein-Jensen medium using standardized procedures. Results: BACTEC MGIT 960 detected 57.1%; BACTEC 9000 MB detected 57.8%; and LJ medium detected 43.5% specimens with Mycobacterium tuberculosis complex (MTBC). BACTEC MGIT 960 had the shortest mean number of days (10.3) to detection, followed by BACTEC 9000 MB (13.2) and LJ medium (26.1). Sign rank test showed all three methods had significant difference in days to detection (each P

To determine whether changing needles during the collection of blood cultures reduces contamination, we randomly assigned 303 children undergoing blood cultures to 1 of 3 groups: no needle changes (blood instilled directly into culture media through the needle used for venipuncture); 1 needle change (before inoculation into the first of 2 culture bottles); and 2 needle changes (before inoculation into each of 2 culture bottles). Each patient's skin was cleansed with povidone-iodine for 60 seconds before venipuncture. We found similar rates of contamination among the 3 groups: no change, 2 of 92 (2.2%); 1 change, 0 of 106 (0.0%); 2 changes, 2 of 105 (1.9%). The combined contamination rate of all 3 groups (1.3%) was significantly lower than the prestudy rate of contamination (4.4%), based on 315 blood cultures (P = 0.04). These data suggest that careful skin preparation is a more important factor than changing needles in reducing contamination during blood culture collection.

A survey of the bacteriological quality of pre‐packed sandwiches on sale in the UK is reported. A total of 91 sandwiches, of which 46 had been on display at ambient temperature, were analysed. Total viable counts were high: 38 per cent of all sandwiches had counts greater than 10⊃7. Coliforms were isolated from 37 per cent of the samples and at levels greater than 10⊃7 in 10 per cent. Listeria monocytogenes was isolated from 17 per cent of all sandwiches. Sandwiches that had been on display at ambient temperature had higher total viable counts and were more likely to contain listeria (28 per cent compared to 7 per cent for those stored at chilled temperatures). A small follow‐up study of sandwich ingredients found high counts in salad. The significance to the public health of the high contamination rate by listeria is unclear. Nevertheless, it would seem appropriate to ensure that sandwiches are always adequately refrigerated.

In order to determine the initial bacterial contamination of corneal donor material the abraded epithelia from 125 donors, i.e., 250 globes, were examined immediately after enucleation. Of these, 49 (19.6%) were sterile, while 201 (80.4%) were contaminated. Monoinfection was identified in 174 globes and mixed infection in 27. The pathogen most frequently isolated was Pseudomonas aeruginosa. Neither the donor's age not the time elapsed between death and enucleation had any influence on the contamination rate. Prolonged hospitalization of donors leads to an increase in gram-negative bacteria. The necessity of antibacterial prophylaxis prior to keratoplasty is pointed out.