Incidence Of Bacterial Contamination Research Articles

The new 222-nm far ultraviolet-C lowers bacterial contamination to endoscopists during esophagogastroduodenoscopy.

This study aimed to clarify the disinfectant efficacy of the 222-nm far ultraviolet-C (UV-C) during esophagogastroduodenoscopy using bacterial cultures. The endoscopists performed esophagogastroduodenoscopy wearing a gown with a tryptic soy agar medium plate on their epigastric region and were divided into two groups: 222-nm far UV-C irradiation (UV group) and non-UV irradiation (non-UV group). As a control group, tryptic soy agar medium plates were placed about 110 cm above the floor. The incidence of bacterial contamination was determined by positive bacterial culture. The cultured bacteria were identified by 16S rRNA sequencing. Additionally, the actual UV exposure dose was measured using the UV-indicator card which changed colors upon exposure to 222 nm far UV-C. The bacterial culture positivity in the UV group (5.03%) was significantly lower than that in the non-UV group (25.76%), p < 0.0001. Most of the bacteria identified in the UV and non-UV groups were normal constituents of the oral flora, including Streptococcus salivarius and Staphylococci. Conversely, pathogenic microbes were found in the control group. The actual exposure doses of 222-nm far UV-C at the endoscopists' face, neck, and epigastric region were 2.09±0.29, 5.89±0.49, and 7.36±0.58 mJ/cm2, respectively. The 222-nm far UV-C irradiation reduced bacterial contamination for endoscopists. It can be used with conventional physical coverings to provide more effective infection control.

Stability of Lidocaine Solutions Following Sodium Bicarbonate Alkalinization

(Reg Anesth Pain Med 2022;47:773–774) It is known that the effectiveness of local anesthesia can be increased by alkalinization using sodium bicarbonate by increasing the fraction of the drug that is undissociated. There is a research gap, however, in examining the degree of alkalinization in different concentrations of lidocaine, its pharmacological stability, and bacterial contamination. This study aimed to fill that gap by examining changes in the amount of unaltered lidocaine according to pH in different concentrations, and by assessing its stability and the incidence of bacterial contamination during preparation.

Needle-free connectors catheter-related bloodstream infections: a prospective randomized controlled trial

BackgroundIn the critically ill, catheter-related bloodstream infection can result from bacterial contamination of infusion hubs of intravascular catheters. Needle-free connectors (NFC) have been suggested to reduce the rate of bacterial contamination and subsequent catheter-related bloodstream infection (CRBSI), but data remains ambiguous. Thus, we tested if a novel NFC would reduce bacterial contamination and subsequent CRBSI.ResultsIn a prospective, randomized controlled trial, surgical ICU patients were randomized to three-way hubs closed by caps or Bionecteur® (Vygon, Inc.) of central venous catheters. Every 72 h, infusion lines were renewed and microbiological samples were taken. Bacterial growth was analyzed by blinded microbiologists. Incidence of bacterial contamination and CRSBI were assessed. Outcome parameters like length of stay on ICU and outcome were retrospectively assessed. Two thousand seven hundred patients were screened, 111 were randomized to the NFC, and 109 into the control group. Finally, 24 patients in the NFC and 23 control patients were analyzed. The majority of samples (NFC 77%; control 70%) found no bacterial growth. Coagulase-negative staphylococci were most commonly detected on CVC samples (NFC 17%; control 21%). We found CRBSI (defined as identical pathogens in blood culture and catheter line tip culture, and clinical manifestations of infection) in two control patients and one patient of the NFC group. Their length of ICU stay did not differ between groups (NFC 19 days; control 23 days).ConclusionThe use of NFC does not influence the rate of bacterial contamination of infusion hubs of central venous catheters.Trial registrationClinicaltrials.gov, NCT02134769. Registered 09 May 2014.

Surrogate markers and their correlation to bacterial contamination and other quality parameters in random-donor platelets by platelet-rich plasma method

Introduction: Bacterial contamination in platelet concentrates (PCs) occurs more frequently than other blood components because of several factors such as storage in oxygen permeable blood bags at 20°C–24°C with continuous agitation which facilitates bacterial growth compared to other blood components which are kept frozen or refrigerated which inhibits bacterial proliferation in them. The purpose of the study was to assess the incidence of bacterial contamination of random-donor PCs and factors associated with its contamination and see how well the surrogate markers such as pH and swirling correlate with the same. Methodology: This was a cross-sectional study which included randomly chosen 500 random-donor platelets (RDPs) in blood bank prepared by platelet-rich plasma method. The samples chosen for the study were from the RDPs on the 5th day of storage after their preparation. pH, platelet count, and swirling in platelets, which act as surrogate markers for bacterial contamination, were checked on the RDP units. About 1–3 ml of PCs was inoculated from the RDP units into labeled culture bottles (BD Bactec Peds Plus/F). Results: Among a total of 499 random-donor PCs that were cultured in the automated BACTEC system for the study, none of them were culture positive. Thirty RDP units in the study were visibly lipaemic whereas 93 RDP units were visibly reddish in appearance. PCs having volumes 70 ml did not affect the swirling, pH, and platelet counts. There was a statistically significant difference between mean pH with RDP units having swirling Grade 2 and 3 and platelet counts with RDP units having swirling Grade 1 and 2. Conclusion: Bacterial contamination though poses a significant risk is a very rare event in a meticulously prepared and stored PCs. Surrogate markers though useful in resource-constrained settings does not correlate optimally with the quality indicators.

Bacterial contamination of platelet products in Dongguan Blood Center, Guangdong Province of China

Background: Due to the importance of their preservation and collection methods, it is critical to assess accurately the risk of bacterial contamination of pooled platelets and apheresis platelets. The incidence of bacterial contamination was observed after four preventive measures (FPM) (including: sterilizing donation environment, screening donors, depleting white blood cells from pooled platelets, and removing the first 15 ml of collected platelet) were taken. Methods: Platelet product samples (pooled and apheresis platelet products) from Dongguan Blood Center were tested by bacterial cultures including initial culture, subculture and identification. If initial culture was positive, subculture would be performed, and if subculture was positive, bacterial identification would be done. 3073 platelet samples were examined in 2006. Platelet samples were collected in 2006 and in 2007 until 2016 after the introduction of FPM. Recipient’s blood and transfused platelets were tested for bacterial cultures when adverse reactions occurred after platelet transfusion. Results: In 2006, 0.72% and 0.47% bacterial contamination were found in pooled platelets and apheresis platelets, respectively. A total of 63 out of 28,711 (0.22%) bacterial contaminations were detected from 2006 to 2016 in pooled and apheresis platelets. From 2007 to 2016, the positive rates of contaminated platelet products declined significantly to 0.33% (pooled platelets) and 0.14% (apheresis platelets). Only 44 positive samples could be identified after the introduction of FPM. In 50 patients with post-platelet transfusion adverse reaction, no bacterial contamination could be identified. Conclusions: Our study demonstrated the improvement of platelet transfusion safety by FPM, The rate of bacterial contamination in pooled platelets is higher than that of apheresis platelets.

Bacterial Contamination of Anaesthetic and Vasopressor Drugs in the Operating Theatres: Ameliyathanelerde Anestetik ve Vazopressör İlaçların Bakteriyel Kontaminasyonu.

The aim of this study was to determine the incidence of bacterial and fungal contamination in anaesthetic and vasopressor drugs before and after use in operating theatres. A cross-sectional study was conducted in the operating theatres of a university hospital. We collected 945 samples of three different drugs, namely, propofol, vecuronium and ephedrine, from 20 operating rooms and refrigerators where the unused drugs were stored. Each drug was divided into two groups, the pre-use group and the post-use group. The pre-use drugs were cultured before the patient received the drug. The post-use drugs were cultured after the patient had received the drug or after the drugs had been transferred to other syringes. The culture results were reported as either positive or negative. Out of the 945 drug samples, 26 (2.8%, 95% confidence interval=1.8%-4.0%) gave a positive culture. Of the 317 propofol samples, 20 (6.3%) were found to have bacterial contamination, 11 in the pre-use group and 9 in the post-use group. Of the 318 ephedrine samples, 6 (1.9%) were found to be positive on culture, one in the pre-use group and five in the post-use group. Vecuronium gave no positive cultures. All organisms were non-pathogenic, and no fungal contamination was found. The incidence of bacterial contamination in anaesthetic and vasopressor drugs was 2.8%. Anaesthetic teams must be aware of contamination issues in anaesthetic drugs that have been prepared for later use and, in order to reduce the risk of contamination, they must improve the methods of administering drugs to patients.

Assessment of metal and bacterial contamination in cultivated fish and impact on human health for residents living in the Mekong Delta

Fish is the main source of animal protein and micronutrients for inhabitants in the lower Mekong River basin. Consumption of fish in the basin ranges from 41 to 51 kg capita−1 year−1. Thus, concerns of human health impacts caused by daily intake of metals contained in fish, and the incidence of bacterial contamination from Listeria and Escherichia coli have been raised. This study was conducted to 1) determine concentrations of metals, fecal indicator organisms, and Listeria spp. in cultivated common diet fish, and 2) assess human health risks as results of fish consumption on a daily basis. The results showed significant impacts of metal accumulation in fish especially from the intensive aquaculture. Chemical use to promote the rapid allometric growth of fish was expected to be the explanation for this finding. Concentrations of metals contained in different fish species were not statistically different with the exceptions of Na, Mn, and Zn. This might be due to the mobility of elements in aquaculture farms. Listeria and E. coli log CFU/g were 1.36 ± 0.11 (standard error) and 1.57 ± 0.1 s.e., respectively with higher counts observed in samples collected in market sites. Lastly, for human health risk assessment via fish consumption, it was found that hazard quotients of consuming As, Cu, and Zn contained in all fish species could contribute adverse health effects to the local residents (hazard quotients higher than 1). Therefore, risk management measures must be promoted and implemented in all study areas to reduce potential risks to local Vietnamese residents.

Repeated reuse of insulin injection syringes and incidence of bacterial contamination among diabetic patients in Jimma University Specialized Hospital, Jimma, Ethiopia

ObjectiveTo determine the level of bacterial contamination of reused insulin syringes among diabetic patients. MethodsA facility based cross sectional study was conducted among diabetic patients. Data on socio-demographic variables, history of injection syringe reuse, and frequency of reuse of syringes were collected using predesigned questionnaire. Finally, the samples from the syringes were cultured according to standard microbiological techniques. ResultsEighteen diabetic patients at Jimma University Hospital participated. A total of 83.3% of participants reused a single injection syringe for >30 consecutive injections, while 16.7%, reused for ≤30 injections. Our results showed 22.2% of syringes were contaminated with methicillin resistant Staphylococcus aureus. ConclusionsWe conclude reuse of syringes is associated with microbial contamination. The findings that 4/18 syringes being contaminated with bacteria is an alarming situation. A mechanism should be designed for patient's to get injection syringes with affordable price. If reusing is not avoidable, reducing number of injections per a single syringe and avoiding needle touching with hand or other non-sterile material may be an alternative to reduce the risk of contamination.

The management of the domestic refrigeration: microbiological status and temperature

Purpose – The purpose of this paper is to provide information on the consumer management of refrigerated food, establish the level and the incidence of bacterial contamination and operating temperatures in domestic refrigerators from north and centre Italy. Design/methodology/approach – A questionnaire was designed involving 24 questions which covered three topics: the socio-demographic data, the domestic management of refrigerated food and general information about the refrigerator. The questionnaire responses were subjected to descriptive statistical analysis and further processed with the multiple correspondence analysis (MCA) and cluster analysis (CA). Based on MCA and CA, 84 refrigerators were selected to assess the temperature and the microbiological status (total viable counts (TVC); Enterobacteriaceae total counts (ETC); Salmonella spp. and Listeria spp.). Findings – Totally, 660 interviews were carried out. The majority of respondents were female (81.4 per cent) and were married (71.4 per cent). Almost an half of them were between 31 and 50 years old (48.2 per cent) and had a secondary school degree (47 per cent). Regarding domestic management of refrigerated food, the majority of respondents (87.2 per cent) were aware of the correct temperature range (1-5°C) for retail refrigerator units, but only 18 per cent of them check the temperature. Listeria monocytogenes and Salmonella spp. were not recovered; Listeria innocua was recovered (2.4 per cent). Regarding the TVC values, the 21.5 per cent of the tested refrigerators were classified as insufficient (from 100 to 104 cfu/cm2) or inadequate (&gt;104 cfu/cm2). Consumer education should be focused in order to reduce foodborne disease. Only safety-conscious consumers can become active partners within the food safety chain. Originality/value – Result obtained from the present survey revealed that consumers are not familiar with their role in the food safety chain and that they allow numerous opportunities for microbiological contamination of food. The study clearly indicates the need for greater consumer education regarding proper domestic refrigerator management. Indeed, appropriate behaviours could make the refrigerator less likely to act as a significant niche for persistence and dissemination of food pathogens.

Incidence of bacterial contamination and predisposing factors during bone and tendon allograft procurement

The aim of this study was to analyze factors contributing to bacteriological contamination of bone and tendon allograft. Between 2008 and 2011, 2,778 bone and tendon allografts obtained from 196 organ and tissue donors or tissue donors only were retrospectively analysed. Several variables were taken into account: donor type (organ and tissue donors vs. tissue donor), cause of death, time interval between death and tissue procurement, duration of the procurement procedure, type of allografts, number of team members, number of trainees members, associated surgical procedures, positivity to haemoculture, type of procurement. The overall incidence of graft contamination was 23 %. The cause of death, the procurement time, the duration of procurement, the associated surgical procedures were not associated with increased risk of contamination. Significant effect on contamination incidence was observed for the number of staff members performing the procurement. In addition, our study substantiated significantly higher contamination rate among bone allografts than from tendon grafts. According to these observations, in order to minimize the contamination rate of procured musculoskeletal allografts, we recommend appropriate donor selection, use of standard sterile techniques, immediate packaging of each allograft to reduce graft exposure. Allograft procurement should be performed by a small surgical team.

Incidence of Bacterial Contamination in Primary THA and Combined Hardware Removal

Prior fracture surgery in the setting of subsequent arthroplasty may confer an increased risk of infection. The current authors retrospectively reviewed 122 patients from 2006 to 2010. Joint aspirations performed preoperatively in two of 52 patients revealed bacterial growth. Preoperative CRP levels were elevated in 22.8% with a mean value of 10.4 mg/L (range 5.5 to 33.3). Intra-operative cultures were performed in 109 patients, with a single patient sample exhibiting bacterial growth (0.9%). Preoperative aspiration showed a sensitivity of 1.0 and specificity of 0.98 (P<0.039) for bacterial contamination. There was no postoperative periprosthetic infection noted. In conclusion the retrieval of internal fixation devices and total hip arthroplasty can be performed safely as a single stage procedure without significantly increasing the risk of periprosthetic infection.

Significant bacterial contamination risk reduction with the use of diversion pouch

Significant efforts have been made towards bacterial risk minimization by limiting the chance of bacteria entering into collected blood, detecting its presence and eliminating them by pathogen reduction technology. Improved skin disinfection and the use of diversion pouch are effective upstream measures to reduce the risk of bacterial sepsis. Here we report on our experience with the use of blood bags with diversion pouch. An observational study was performed to compare the bacterial contamination rate for two periods of time, i.e. before and after introduction of diversion pouch into blood bags. The incidence of bacterial contamination was monitored by the existing bacterial surveillance programme using pooled samples from 5 units of random donor platelets underwent aerobic culture in the BacT/ALERT 3D system. Between 1 June 2004 and 31 May 2006 (blood bag without diversion pouch), 50 (0·0213%) out of 234,252 units of random donor platelets were found to have bacteria on culture whereas 15 (0·0057%) isolates out of 262,156 units were found from 1 June 2007 to 31 May 2009 (after diversion pouch was introduced). Overall, there was an 85% reduction in bacterial contaminated risk due to skin flora (P < 0·0001) but an increasing trend of detection of non skin flora such as Streptococcus bovis was noted. Integration of diversion pouch into blood bags to divert the first 30 mL blood during blood collection on top of the current skin disinfection protocol can significantly reduce the risk of bacterial contamination.

Incidence of bacterial contamination in infusion set needles

We examined the incidence and types of bacterial contamination in 265 infusion set needles in adult critically ill patients. Bacterial contamination was detected in 15 samples (5.7%), and a total of 17 organisms were isolated. Ten were coagulase-negative staphylococci (CNS) and Staphylococcus aureus, and the remainder were α-Streptococcus, Corynebacterium, and gram-negative rods. Although the contamination was not directly related to catheter-related bloodstream infections exchanging infusion bottles can cause intraluminal contamination and is a possible route of these infections.

Scrub the Hub! Catheter Needleless Port Decontamination

THE central venous catheter (CVC) is an essential tool in the care of critically ill and high-risk intraoperative patients. Catheter- related bloodstream infection (CR-BSI) related to CVC insertion technique has been greatly reduced by the use of preventive protocols.1However, late CR-BSI remains a significant threat to patient safety and healthcare cost containment. Appropriate CVC maintenance may be the most important factor in the prevention of late CR-BSI.2Even transient improper CVC maintenance (e.g. , with perioperative drug administration) may cause life-threatening CR-BSI.We examined the effect of scrub duration on macroscopic contamination of needleless CVC connector hubs to illustrate the importance of hub cleaning. We applied commercially available fluoresceine-impregnated powder (Brevis Corporation, Salt Lake City, UT) to CVC hubs and subsequently scrubbed the hubs with 70% isopropyl alcohol pads for 0 (control), 5, 10, and 15 s. Using ultraviolet light, we exposed residual fluorescent powder on the CVC hub.We found a direct relationship between scrub duration and powder contamination, particularly in areas with complex 3-dimensional topography. The correlation between this finding and the incidence of bacterial contamination is unclear, although Menhay has previously questioned the efficacy of a 3–5 s alcohol scrub for heavily contaminated CVC hubs.3Anesthesiologists are encouraged to follow best-practice guidelines for CVC maintenance, including attention to disinfection of CVC hubs with isopropyl alcohol pads before syringe or infusion tubing connection. Future studies are needed to determine whether increasing scrub duration will also reduce bacterial colonization and CR-BSI outcomes.The authors thank Herbert Mann, B.S., Johns Hopkins Hospital Pediatric Intensive Care Unit, The Johns Hopkins Hospital, Baltimore, Maryland, whose artistic and photographic guidance were invaluable in the production of the image.

Bacterial Contamination of Needles Used for Intravitreal Injections: A Prospective, Multicenter Study

Purpose: To determine the incidence of bacterial contamination of needles used for intravitreal injections.Methods: Patients undergoing intravitreal injections were enrolled prospectively. No pre-injection antibiotics were administered. Following povidone–iodine irrigation, conjunctival cultures were taken and the injection was performed. The needle was cultured. A dry control needle was exposed to the surgical field and cultured.Results: No patients developed endophthalmitis. Eighteen injection needles (18%) yielded positive bacterial growth. The most commonly encountered organisms were Propionibacterium acnes (n = 8) and Staphylococcus epidermidis (n = 6). Four control needles showed positive growth, in 2 cases with the same organism as a matching positive used needle. The difference between contamination rates of used and control needles was significant (p = .002, McNemar’s test).Conclusions: Bacterial contaminants are present on a substantial proportion of needles. Since the needle contacts both the ocular surface and the vitreous, it is possible that inoculation of the vitreous cavity occurs in such cases.

A prospective clinical trial on prevention of catheter contamination using the hub protection cap for needleless injection device

Catheter hub contamination has been recognized as a source of catheter-related bloodstream infections. We have investigated the efficacy of a protection cap for a needleless injection device in preventing intraluminal catheter contamination, compared with a conventional 3-way stopcock. Adult patients requiring an intravascular catheter placement for at least 48 hours in an intensive care unit were randomly assigned to receive either the needleless injection device with protection cap (test group, n = 31, number of devices = 151) or with a conventional 3-way stopcock (comparator group, n = 33, number of devices = 179). To evaluate intraluminal contamination, we examined the bacteria isolated in the inline bacterial filters, which were attached downstream of the injection ports. The incidence of bacterial contamination was significantly different between the groups (test group 2/151 (1.3%) vs comparator group 11/179 (6.2%), P = .04). There was no correlation between the microbial contamination rate and the in situ time of catheter or numbers of injections. The protection cap for needleless injection devices decreased microbial transfer from the injection port to the intraluminal fluid pathway and lowered the risk of catheter-related bloodstream infections.

Microbial Contamination in Burn Patients Undergoing Urgent Intubation as Part of Their Early Airway Management

Inhalation injuries occur in approximately one third of all major burns and account for a significant number of deaths in burn patients each year. Previous studies have examined ventilator-associated pneumonia in patients with inhalation injury, but no study to date has evaluated the incidence of bacterial contamination of the airways on admission in patients with inhalation injuries. Because pulmonary complications have been found to cause or directly contribute to mortality in as high as 77% of patients, with combined inhalation injury and thermal injury, early detection of community-acquired pneumonia may significantly alter treatment outcomes. The authors conducted a retrospective review of all burn patients with early intubation and inhalation injury admitted between January 1, 2004 and December 31, 2006 who underwent bronchoscopy with bronchoalveolar lavage (BAL) within 24 hours of admission. Seventy-four consecutive patients fulfilled the inclusion criteria. Age, sex, percentage of total body surface area (%TBSA), presence of alcohol, site of intubation, grade of injury, and BAL results were examined. Analysis revealed a patient population that was 67.6% male, with a 42.0 +/- 17.1-year-old mean age, 27.0 +/- 24.7 %TBSA average burn, 1.6 +/- 1.2 inhalation grade, 17.8 +/- 24.4 ventilator days requirement, 27.3 +/- 31.4 days of length of stay, and 21.6% mortality. BAL results were grouped into four categories: 1) No growth, 2) Normal flora, 3) <100,000 colony-forming units (cfu), and 4) >100,000 cfu. By this criteria, 13 patients (17.6%) had no growth, 22 (29.7%) had normal flora, 27 (36.5%) had <100,000 cfu, and 12 (16.2%) had >100,000 cfu on the initial BAL. Therefore, 53% grew pathogenic organisms and 16% had >100,000 cfu on BAL with initial bronchoscopy. The predominant organisms were gram-positive cocci, with Streptococcus viridans found in 15 patients (20%), Staphylococcus aureus in eight (11%), and Streptococcus pneumonia in four (6%). Analysis of the patients with the highest bacterial loads revealed that they were 75% female and had a trend toward an increased ventilator requirement and longer length of stay. Patients with combined thermal and inhalation injury requiring urgent intubation have a high incidence of bacterial bronchial contamination. Inhalation injury creates a damaged tracheobronchial mucosa and early intubation provides a portal for bacterial contamination. Further studies with a larger patient population and randomization to treatment and nontreatment of the BAL culture results may show statistically significant differences in ventilator days, length of stay, and mortality.

Effect of genetic resistance of the hen toSalmonellacarrier-state on incidence of bacterial contamination: synergy with vaccination

Salmonella is one of the major sources of toxi-infections in humans. The association between egg consumption and Salmonella outbreaks is a serious economic and public health problem. To control the incidence of Salmonella in poultry flocks, many prophylactic means have been developed but none allows a total reduction of the risk. In a previous study, we derived mathematical models for Salmonella transmission and used them to appreciate the most important factors of variation of egg contamination rate and thus of risk of human contamination. Thanks to recent data of a selection experiment for increased or decreased rate of carrier-state (also called divergent selection), we showed that mixing, in an equal proportion, animals issued from a line selected for a lower (denoted Sal-) or higher propensity to carry Salmonella (denoted Sal+) results in a reduction by half of the maximal percentage of contaminated animals but does not accelerate the extinction of the disease. Vaccination and selection should be synergic, since a former contamination reduces the maximal prevalence by 45 and 71%, respectively, in Sal+ or Sal- flocks respectively. These results show the interest in the introduction, even at a rather moderate percentage, of animals selected for a reduced rate of Salmonella carrier-state within commercial flocks. This could be achieved by using one or more selected lines in commercial crosses. These results must be confirmed experimentally while the mathematical model could be extended with minor modifications to other animal species or pathogenic species.

Food Safety Knowledge of Consumers and the Microbiological and Temperature Status of Their Refrigerators

The objectives of this study were to examine domestic food safety knowledge levels of consumers, establish the levels and incidence of bacterial contamination and operational temperatures in domestic refrigerators, and identify areas in which consumer food safety education is necessary in Ireland. A food safety knowledge questionnaire applied to a representative sample of households (n = 1,020) throughout the island of Ireland found the gaps in consumer food safety knowledge. Analysis of swab samples (n = 900) recovered from the domestic refrigerators in these households showed average total viable counts of 7.1 log CFU/cm2 and average total coliform counts of 4.0 log CFU/cm2. Analysis of swab samples also detected the incidence of Staphylococcus aureus (41%), Escherichia coli (6%), Salmonella enterica (7%), Listeria monocytogenes (6%), and Yersinia enterocolitica (2%). Campylobacter jejuni and E. coli O157:H7 were not detected in domestic refrigerators. The temperature profiles of a subset of the sampled refrigerators (100) were monitored for 72 h, and 59% were found to operate, on average, at temperatures above the recommended 5°C. Knowledge and temperature survey results varied considerably, but consumers who scored better in terms of basic food safety knowledge had reduced levels of bacterial contamination in their refrigerators and reported a reduced incidence of food-associated illnesses. This study confirms the effect of basic food hygiene knowledge on hygienic practice and identifies specific areas for emphasis in the development and delivery of effective food safety risk communication messages to consumers.

Evaluation of Storage Conditions and Bacterial Proliferation in Blood Components

616 LABMEDICINE Volume 35 Number 10 October 2004 labmedicine.com The safety of the blood supply, particularly the risk of transfusion transmitted infections, is a great public health concern. The transfusion of bacterially contaminated blood and blood products may have severe or even fatal consequences.1-4 Bacterial contamination of blood components is the most frequently reported cause of transfusion-related fatalities reported to the FDA after hemolytic transfusion reactions, accounting for more than 10% [77/694] of transfusion-associated fatalities from 1985 to1999.5 Of these, a majority (62%) were associated with the transfusion of bacterially contaminated platelets, while a minority (38%) were associated with transfusion of bacterially contaminated red cells. Platelets are stored at 22°C to 24°C and as a result are more likely to support bacterial growth than are the red cells, which are refrigerated between 1°C to 6°C. Review of literature6-16 on bacterial contamination of blood components reveals that there are no definite and clear cut guidelines or effective measures being practiced to tackle this problem, as not all contaminated blood components lead to overt clinical bacterial infections, and often there is lack of suspicion on the part of clinicians. Thus, there is not enough data in the literature to document the exact frequency of transfusion-transmitted bacterial infections, but reported values are around 0.1%.6 Recent figures estimate a prevalence of 0.2% for whole blood,6 0.002% to 1.0% for packed red cells, and 0.04% to 10% for platelets depending upon processing, storage, and the method of culture (Table 1).7-13 Much attention has been paid to the storage conditions and prevention of possible contamination during the collection and preparation of blood components in the blood bank,14-16 but the storage conditions and handling of blood and blood components outside the blood bank (ie, various wards and operation theaters) have never been looked into seriously. Keeping this in mind, we tried to evaluate: 1. The storage conditions within and outside the blood bank by sending random cultures of components stored in the blood bank and single cultures from received-back units from various wards and operation theaters. 2. The overall incidence of bacterial contamination of blood components at our center and the resultant morbidity and mortality over a period of 3 years, from January 1999 to December 2001. Evaluation of Storage Conditions and Bacterial Proliferation in Blood Components