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Prolonged survival of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on environmental surfaces and personal protective equipment may lead to these surfaces transmitting this pathogen to others. We sought to determine the effectiveness of a pulsed-xenon ultraviolet (PX-UV) disinfection system in reducing the load of SARS-CoV-2 on hard surfaces and N95 respirators.
Chamber slides and N95 respirator material were directly inoculated with SARS-CoV-2 and were exposed to different durations of PX-UV.
For hard surfaces, disinfection for 1, 2, and 5 minutes resulted in 3.53 log10, >4.54 log10, and >4.12 log10 reductions in viral load, respectively. For N95 respirators, disinfection for 5 minutes resulted in >4.79 log10 reduction in viral load. PX-UV significantly reduced SARS-CoV-2 on hard surfaces and N95 respirators.
With the potential to rapidly disinfectant environmental surfaces and N95 respirators, PX-UV devices are a promising technology to reduce environmental and personal protective equipment bioburden and to enhance both healthcare worker and patient safety by reducing the risk of exposure to SARS-CoV-2.
The turkey (Meleagris gallopavo) was independently domesticated in Mesoamerica and the Southwest, the latter as the only case of Native American animal domestication north of Mexico. In the upland (non-desert) portion of the American Southwest, distinctive closely related mtDNA lineages belonging to haplogroup H1 (thought to indicate domestication) occur from ca. 1 A.D. (Basketmaker II period) through early historic times. At many sites, low frequencies of lineages belonging to haplogroup H2 also occur, apparently derived from the local Merriam’s subspecies. We report genetic, stable isotope, and coprolite data from turkey remains recovered at three early sites in SE Utah and SW Colorado dating to the Basketmaker II, III, and early Pueblo II periods. Evidence from these and other early sites indicates that both the H1 and H2 turkeys had a predominantly maize-based diet similar to that of humans; prior to late Pueblo II times, the birds were kept primarily to provide feathers for blankets and ritual uses; and ritualized burials indicate turkeys’ symbolic value. We argue that viewing individuals from the H1 and H2 haplogroups as “domestic” versus “wild” is an oversimplification.
The transfusion of blood and blood components is associated with a very low but ever-present risk of infection. It is estimated that 1 in every 2000 units of blood may carry an infectious agent and that about 4 in 10 000 recipients develop a chronic disease or die as a result of receiving contaminated blood. A wide variety of viral, bacterial, and parasitic agents have been associated with blood transfusion (Table 106.1). Concerns have also been raised about the potential for transmission of Creutzfeldt–Jakob disease (CJD) and its new variant (vCJD) through blood products. However, no human episodes of CJD or vCJD have been definitively linked to blood or blood component transfusion to date, and case–control studies have not found blood transfusion to be a risk factor for CJD. The risk of viral transmission has been markedly reduced with improved screening, particularly using nucleic acid testing (NAT). The risk is now estimated to be 1 in 2 million units for human immunodeficiency virus (HIV) or hepatitis C virus (HCV) and approximately 1 in 200 000 units for hepatitis B virus (HBV). Because the risk of viral or parasitic infection is very low and blood is screened for HCV, HBV, HIV, and human T-cell lymphoma/leukemia virus (HTLV) 1, the remainder of this chapter focuses on bacterial complications of blood transfusion, which can be diagnosed and treated.
Healthcare-associated infections (HAIs) are an important cause of morbidity and mortality worldwide. During the period from 2002 through 2004, a group of Italian hospitals was recruited to conduct HAI point-prevalence surveys.
Three point-prevalence surveys.
A total of 9,609 patients were surveyed.
The overall frequency of HAI was 6.7% (645 infections among the 9,609 surveyed patients). The most frequent HAIs were lower respiratory tract infections, which accounted for 35.8% (231 of 645 HAIs) of all HAIs, followed by urinary tract infections (152 [23.6%] of 645 HAIs), bloodstream infections (90 [14.0%] of 645 HAIs), and surgical site infections (79 [12.2%] of 645 HAIs). In both multivariate and univariate analysis, invasive procedures, duration of stay, chemotherapy, trauma, coma, and the location of the hospital were all factors statistically significantly associated with the occurrence of an HAL Enterobacteriaceae were the most common isolates recovered in medical and surgical wards, whereas gram-negative aerobic bacilli were the most common isolates recovered in intensive care units. Approximately one-half of all of the patients surveyed were receiving antibiotics at the time of our study; the most used antibiotic classes were fluoroquinolones in medical wards, cephalosporins in surgical wards, and penicillins and glycopeptides in intensive care units.
Our study emphasizes the need for implementing further HAI surveillance to provide the National Health System with proper tools to prevent and manage infection in hospitalized patients.
The goal of this effort was to reduce central venous catheter (CVC)-associated bloodstream infections (BSIs) in pediatric intensive care unit (ICU) patients by means of a multicenter evidence-based intervention.
An observational study was conducted in 26 freestanding children's hospitals with pediatric or cardiac ICUs that joined a Child Health Corporation of America collaborative. CVC-associated BSI protocols were implemented using a collaborative process that included catheter insertion and maintenance bundles, daily review of CVC necessity, and daily goals. The primary goal was either a 50% reduction in the CVC-associated BSI rate or a rate of 1.5 CVC-associated BSIs per 1,000 CVC-days in each ICU at the end of a 9-month improvement period. A 12-month sustain period followed the initial improvement period, with the primary goal of maintaining the improvements achieved.
The collaborative median CVC-associated BSI rate decreased from 6.3 CVC-associated BSIs per 1,000 CVC-days at the start of the collaborative to 4.3 CVC-associated BSIs per 1,000 CVC-days at the end of the collaborative. Sixty-five percent of all participants documented a decrease in their CVC-associated BSI rate. Sixty-nine CVC-associated BSIs were prevented across all teams, with an estimated cost avoidance of $2.9 million. Hospitals were able to sustain their improvements during a 12-month sustain period and prevent another 198 infections.
We conclude that our collaborative quality improvement project demonstrated that significant reduction in CVC-associated BSI rates and related costs can be realized by means of evidence-based prevention interventions, enhanced communication among caregivers, standardization of CVC insertion and maintenance processes, enhanced measurement, and empowerment of team members to enforce adherence to best practices.
Several medical devices used during hemodynamic procedures, particularly angiographic diagnostic and therapeutic cardiac catheters, are manufactured for single use only. However, reprocessing and reuse of these devices has been reported, to determine the frequency of reuse and reprocessing of single-use medical devices used during hemodynamic procedures in Brazil and to evaluate how reprocessing is performed.
National survey, conducted from December 1999 to July 2001.
Most of the institutions affiliated with the Brazilian Society of Hemodynamic and Interventional Cardiology were surveyed by use of a questionnaire sent in the mail.
The questionnaire response rate was 50% (119 of 240 institutions). Of the 119 institutions that responded, 116 (97%) reported reuse of single-use devices used during hemodynamic procedures, and only 26 (22%) reported use of a standardized reprocessing protocol. Cleaning, flushing, rinsing, drying, sterilizing and packaging methods varied greatly and were mostly inadequate. Criteria for discarding reused devices varied widely. Of the 119 institutions that responded, 80 (67%) reported having a surveillance system for adverse events associated with the reuse of medical devices, although most of these institutions did not routinely review the data, and only 38 (32%) described a training program for the personnel who reprocessed single-use devices.
The reuse of single-use devices used during hemodynamic procedures was very frequent in hospitals in Brazil. Basic guidance on how to reuse and reprocess single-use medical devices is urgently needed, because, despite the lack of studies to support reusing and reprocessing single-use medical devices, such devices are necessary in limited-resource areas in which these practices are current.
The costs of living with wildlife are assessed using Namibian subsistence farmers' willingness to pay (WTP) for deterrents to attacks on crops and livestock. A utility-theoretic approach jointly estimates household WTP for deterrent programs in two ‘currencies’: maize and cash. This has a double payoff. Use of a non-cash staple increases respondent comprehension and provides more information about preferences, improving the accuracy of results. The household shadow value of maize is also identified. Significant costs from living with elephants and other types of wildlife are demonstrated. Compensation for farmers may be warranted on equity and efficiency grounds. Uncontrolled domestic cattle generate even higher costs to farmers than wildlife, highlighting the need to clarify property rights among these farmers.
The transfusion of blood and blood components is associated with a very low but ever-present risk of infection. It is estimated that 1 in every 2000 units of blood may carry an infectious agent and that about 4 in 10 000 recipients develop a chronic disease or die as a result of receiving contaminated blood. A wide variety of viral, bacterial, and parasitic agents have been associated with blood transfusion (Table 104.1). Concerns have also been raised about the potential for transmission of Creutzfeldt–Jakob disease (CJD) and its new variant (nv-CJD) through blood products. However, no human episodes of CJD or nv-CJD have been causally liked to blood transfusion, and case–control studies have not found blood transfusion to be a risk factor for CJD. The risk of viral transmission has been markedly reduced with improved screening, particularly using nucleic acid testing (NAT). The risk is now estimated to be 1 in 2 million units for human immunodeficiency virus (HIV) or hepatitis C virus (HCV) and approximately 1 in 200 000 units for hepatitis B virus (HBV). Because the risk of viral or parasitic infection is very low and blood is screened for HCV, HBV, HIV, and human T-cell lymphoma/leukemia virus (HTLV) 1, the remainder of this chapter focuses on bacterial complications of blood transfusion, which can be diagnosed and treated.
We conducted an intervention study to assess the impact of the use of an alcohol-chlorhexidine-based hand sanitizer on surgical site infection (SSI) rates among neurosurgical patients in Ho Chi Minh City, Vietnam.
A quasi-experimental study with an untreated control group and assessment of neurosurgical patients admitted to 2 neurosurgical wards at Cho Ray Hospital between July 11 and August 15, 2000 (before the intervention), and July 14 and August 18, 2001 (after the intervention). A hand sanitizer with 70% isopropyl alcohol and 0.5% Chlorhexidine gluconate was introduced, and healthcare workers were trained in its use on ward A in September 2000. No intervention was made in ward B. Centers for Disease Control and Prevention definitions of SSI were used. Patient SSI data were collected on standardized forms and were analyzed using Stata software (Stata).
A total of 786 patients were enrolled: 377 in the period before intervention (156 in ward A and 221 in ward B) and 409 in the period after intervention (159 in ward A and 250 in ward B). On ward A after the intervention, the SSI rate was reduced by 54% (from 8.3% to 3.8%; P = .09), and more than half of superficial SSIs were eliminated (7 of 13 vs 0 of 6 in ward B; P = .007). On ward B, the SSI rate increased by 22% (from 7.2% to 9.2%; P = .8). In patients without SSI, the median postoperative length of stay and the duration of antimicrobial use were reduced on ward A (both from 8 to 6 days; P <.001) but not on ward B.
Our study demonstrates that introduction of a hand sanitizer can both reduce SSI rates in neurosurgical patients, with particular impact on superficial SSIs, and reduce the overall postoperative length of stay and the duration of antimicrobial use. Hand hygiene programs in developing countries are likely to reduce SSI rates and improve patient outcomes.
To characterize red eye reactions occurring within 24 hours after receipt of units of leukocyte-reduced red blood cells, determine their etiology, and investigate their potential link to transfusion.
We conducted a survey of transfusion facilities nationwide to determine the scope and magnitude of the reactions; performed case-control and cohort studies among transfused patients at the facility where most reactions occurred; and performed animal experiments, using cellulose acetate derivatives extracted from leukocyte-reduction filters and filter precursors, to reproduce reactions.
From January 1, 1997, through January 15, 1998, we identified 159 reactions in 117 patients from 17 states. Reactions were characterized by conjunctival erythema or hemorrhage (in 100% of patients), eye pain (in 62%), photophobia (in 46%), and decreased visual acuity (in 32%). Symptom onset occurred 1-24 hours after initiation of transfusion and resolved within a median of 5 days. Reactions were associated with transfusion sessions that included units of red blood cells filtered with a specific brand of filter, the LeukoNet filter (HemaSure) (odds ratio, 100.4; P< .001). There was a dose-response relationship between the number of LeukoNet-filtered units transfused and the attack rate for reactions, ranging from 0.8% among sessions in which 1 unit was transfused to 27.3% among sessions in which 3 or more units were transfused (P< .001). A similar ocular syndrome was elicited in rabbits injected with cellulose acetate derivatives extracted from unused LeukoNet filters or filter precursors. No reactions were reported after LeukoNet filters were withdrawn from the market.
This transfusion-associated red eye syndrome was linked to a specific brand of leukocyte-reduction filter and likely resulted from cellulose acetate derivatives leached from the filter membrane.
A 19-item survey instrument was designed and mailed by the Infectious Diseases Society of America to its membership to determine the media preferred by infectious diseases physicians for continuing medical education on general topics and on antimicrobial resistance. The objective of the survey was to offer the developers of educational programs knowledge on which to base more-effective ways to deliver educational materials to physicians in this specialty.
To compare the cumulative incidence of infections acquired in the pediatric intensive care unit (PICU) and neonatal intensive care unit (NICU).
Estimation of the cumulative incidence of infections with data obtained from the Pediatric Prevention Network (PPN) point-prevalence survey and observed rates from the National Nosocomial Infections Surveillance (NNIS) system.
Ten hospitals participated in both the PPN survey and NNIS system.
All patients present on the PPN survey dates (August 4, 1999, or February 1, 2000) in the NICUs or PICUs of the PPN hospitals were included in the survey. Point prevalences for PICU-acquired and for NICU-acquired infections at these hospitals were calculated from the survey data. The cumulative incidence rates were estimated from the point prevalence rates using a standard formula and a standard method for calculating the time to recovery (ie, on the basis of the assumption that discontinuance of antimicrobial therapy indicates recovery from infection); alternate methods to judge the time to recovery from infection were also explored.
The average cumulative incidence of intensive care unit-acquired infection for NICUs and PICUs combined (all units), as measured by NNIS, was 14.1 cases per 100 patients; in comparison, the prevalence was 14.06 cases for 100 patients (median difference, —0.95 cases per 100 patients; 95% confidence interval, —4.6 to 5.0 cases per 100 patients), and the estimated cumulative incidence using the standard method of calculating the time to recovery was 13.8 cases per 100 patients (median difference, —1.5 cases per 100 patients; 95% confidence interval, —9.1 to 2.9 cases per 100 patients). Estimates of cumulative incidence using alternate methods for calculation of time to recovery did not perform as well (range, 4.9-100.9 cases per 100 patients). The average incidence density for all units, as measured by the NNIS system, was 6.8 cases per 1,000 patient-days, and the estimate of incidence density using the standard method of calculating the time to recovery was 3.6 cases per 1,000 patient-days (median difference, 4.3 cases per 1,000 patient-days; 95% confidence interval, 0.9 to 9.2 cases per 1,000 patient-days). Estimated incidence densities using alternate methods for determining recovery time correlated closely with observed incidence densities.
In this patient population, the simple point prevalence provided the best estimate of cumulative incidence, followed by use of a standard formula and a standard method of calculating the time to recovery. Estimation of incidence density using alternate methods performed well. The standard formula and method may provide an even better estimate of cumulative incidence than does simple prevalence in general populations.
Of 33,111 patients admitted to a large hospital in Vietnam from November 2000 through July 2001, a total of 303 were undergoing hemodialysis and had pyrogenic reactions (ie, fever and/or rigors). Ten case patients (3.3%) had documented bacteremia; pathogens were largely waterborne microorganisms. Pyrogenic reactions in case patients might have occurred because of suboptimal water quality or inadequate dialyzer reprocessing procedures.
To assess influenza vaccination rates of healthcare workers (HCWs) in neonatal intensive care units (NICUs), pediatric intensive care units (PICUs), and oncology units in Pediatric Prevention Network (PPN) hospitals.
Infection control practitioners and HCWs in NICUs, PICUs, and oncology units.
In November 2000, posters, electronic copies of a slide presentation, and an influenza fact sheet were distributed to 32 of 76 PPN hospitals. In January 2001, a survey was distributed to PPN hospital participants to obtain information about the immunization campaigns. On February 7, 2001, a survey of influenza immunization was conducted among HCWs in NICU, PICU, and oncology units at participating hospitals.
Infection control practitioners from 19 (25%) of the 76 PPN hospitals completed the surveys. The median influenza immunization rate was 43% (range, 12% to 63%), with 7 hospitals exceeding 50%. HCWs (n = 1,123) at 15 PPN hospitals completed a survey; 53% of HCWs reported receiving influenza immunization. Immunization rates varied by work site: 52% in NICUs and PICUs compared with 60% in oncology units. Mobile carts and PPN educational fact cards were associated with higher rates among these subpopulations (P < .001) (361 [63%] of 575 vs 236 [44%] of 541 for mobile carts; 378 [60%] of 633 vs 219 [45%] of 483 for fact cards).
Despite delayed distribution of influenza vaccine during the 2000–2001 season, immunization rates at 7 hospitals and among HCWs in high-risk units exceeded the National Association of Children's Hospitals and Related Institutions goal of 50%.
To determine the magnitude of van-comycin-resistant enterococci (VRE) in three counties in the San Francisco Bay area.
Active laboratory-based surveillance for VRE from January 1995 through December 1996 and a laboratory-based and hospital-based questionnaire survey for 1993 to 1994 and 1997 to 1998.
All 33 general acute care hospitals in three counties in the San Francisco Bay area.
Laboratories and infection control professionals serving these hospitals, and staff of the California Emerging Infections Program.
The number of hospitals reporting 1 or more patient clinical VRE isolates was 1 (3%) in 1993, 7 (21%) in 1994, 31 (94%) in 1995, and 33 (100%) in 1996 to 1998. The number of patient isolates increased from 1 in 1993 to 24 in 1994, 176 in 1995,429 in 1996, 730 in 1997, and 864 in 1998. Most VRE isolates in 1995 and 1996 were from urine and were not associated with serious clinical disease. However, the number of isolates from blood increased from 9 (6% of total) in 1995 to 44 (12% of the total) in 1996, 90 (14%) in 1997, and 100 (13%) in 1998.
Our data document the rapid emergence and increase of VRE in all hospitals in three counties in the San Francisco Bay area during 1994 to 1998. Infection control measures for VRE together with antibiotic utilization programs should be implemented to limit further spread.