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To help facilities prepare for potential future cases of severe acute respiratory syndrome (SARS).
Design and Participants:
The Centers for Disease Control and Prevention (CDC), assisted by members of professional societies representing public health, healthcare workers, and healthcare administrators, developed guidance to help facilities both prepare for and respond to cases of SARS.
Interventions:
The recommendations in the CDC document were based on some of the important lessons learned in healthcare settings around the world during the SARS outbreak of 2003, including that (1) a SARS outbreak requires a coordinated and dynamic response by multiple groups; (2) unrecognized cases of SARS-associated coronavirus are a significant source of transmission; (3) restricting access to the healthcare facility can minimize transmission; (4) airborne infection isolation is recommended, but facilities and equipment may not be available; and (5) staffing needs and support will pose a significant challenge.
Conclusions:
Healthcare facilities were at the center of the SARS outbreak of 2003 and played a key role in controlling the epidemic. Recommendations in the CDC's SARS preparedness and response guidance for healthcare facilities will help facilities prepare for possible future outbreaks of SARS.
To rapidly establish a temporary isolation ward to handle an unexpected sudden outbreak of severe acute respiratory syndrome (SARS) and to evaluate the implementation of exposure control measures by healthcare workers (HCWs) for SARS patients.
Design:
Rapid creation of 60 relatively negative pressure isolation rooms for 196 suspected SARS patients transferred from 19 hospitals and daily temperature recordings of 180 volunteer HCWs from 6 medical centers.
Setting:
A military hospital.
Results:
Of the 196 patients, 34 (17.3%) met the World Health Organization criteria for probable SARS with positive results of serologic testing for SARS-associated coronavirus (SARS-CoV), reverse transcriptase polymerase chain reaction (RT-PCR) from nasopharyngeal or throat swabs for SARS-CoV, or both. Seventy-four patients had suspected SARS based on unprotected exposure to SARS patients; three of them had positive results on RT-PCR but negative serologic results. The remaining 88 patients did not meet the criteria for a probable or suspected SARS diagnosis. Of the 34 patients with probable SARS, 13 were transferred to medical centers to receive mechanical ventilation due to rapid deterioration of chest x-ray results, and three patients died of SARS despite intensive therapy in medical centers. During the study period, one nurse developed probable SARS due to violation of infection control measures, but there was no evidence of cross-transmission to other HCWs.
Conclusions:
Despite the use of full personal protection equipment, the facility failed to totally prevent exposures of HCWs to SARS but minimized the risk of nosocomial transmission. Better training and improvements in infection control infrastructure may limit the impact of SARS.
To compare the public's knowledge and perception of SARS and the extent to which various precautionary measures were adopted in Hong Kong and Singapore.
Design:
Cross-sectional telephone survey of 705 Hong Kong and 1,201 Singapore adults selected by random-digit dialing.
Results:
Hong Kong respondents had significantly higher anxiety than Singapore respondents (State Trait Anxiety Inventory [STAI] score, 2.06 vs 1.77; P < .001). The former group also reported more frequent headaches, difficulty breathing, dizziness, rhinorrhea, and sore throat. More than 90% in both cities were willing to be quarantined if they had close contact with a SARS case, and 70% or more would be compliant for social contacts. Most respondents (86.7% in Hong Kong vs 71.4% in Singapore; P < .001) knew that SARS could be transmitted via respiratory droplets, although fewer (75.8% in Hong Kong vs 62.1% in Singapore; P < .001) knew that fomites were also a possible transmission source. Twenty-three percent of Hong Kong and 11.9% of Singapore respondents believed that they were “very likely” or “somewhat likely” to contract SARS during the current outbreak (P < .001). There were large differences between Hong Kong and Singapore in the adoption of personal precautionary measures. Respondents with higher levels of anxiety, better knowledge about SARS, and greater risk perceptions were more likely to take comprehensive precautionary measures against the infection, as were older, female, and more educated individuals.
Conclusion:
Comparative psychobehavioral surveillance and analysis could yield important insights into generic versus population-specific issues that could be used to inform, design, and evaluate public health infection control policy measures.
To investigate and determine the cause of an outbreak of Mycobacterium mucogenicum bacteremias in bone marrow transplant (BMT) and oncology patients.
Design:
Case–control study and culturing of hospital water sources. Isolates were typed using molecular methods.
Setting:
University-affiliated, tertiary-care medical center.
Patients:
Case-patients were adult and pediatric BMT patients or hematopoietic stem cell transplant (BMT) (n = 5) and oncology (n = 1) patients who were diagnosed as having M. mucogenicum bacteremia during the study period of August through November 1998. Two control-patients were selected for each case-patient matched by age, time of hospitalization, inpatient unit, and type of patient (BMT or oncology).
Results:
There were no significant differences between case-patients and control-patients regarding intravenous products received or procedures performed, frequency of bathing, neutropenia, or steroid use. Nontuberculous mycobacteria were isolated from several water sources at the medical center including tap water from sinks and showerheads, the hospital hot water source, and the city water supply to the hospital. Analysis by multilocus enzyme electrophoresis and randomly amplified polymorphic DNA showed a match between one patient's blood isolate and an isolate from shower water from that patient's prior hospital room.
Conclusions:
The cause of the outbreak seemed to be water contamination of central venous catheters (CVCs) during bathing. A recommendation in early 2001 that CVCs be protected from water during bathing was followed by no M. mucogenicum bacteremias during the second half of 2001, only one in 2002, and none at all during 2003.
Mycobacterium simiae is found primarily in the southwestern United States, Israel, and Cuba, with tap water as its suspected reservoir. Our institution saw an increase in M. simiae isolates in 2001. An investigation into possible contaminated water sources was undertaken.
Design:
Environmental cultures were performed from water taps in the microbiology laboratory, patient rooms, points in the flow of water to the hospital, and patients' homes. Patient and environmental M. simiae were compared by PFGE.
Setting:
Military treatment facility in San Antonio, Texas.
Patients:
All patients with cultures positive for M. simiae between January 2001 and April 2002. Medical records were reviewed.
Results:
M. simiae was recovered from water samples from the hospital, patients' home showers, and a well supplying the hospital. A single PFGE clone was predominant among water isolates (9 of 10) and available patient isolates (14 of 19). There was an association between exposure to hospital water and pulmonary samples positive for the clonal M. simiae strain (P = .0018). Only 3 of 22 culture-positive patients met criteria for M. simiae pulmonary disease. Of them, two had indistinguishable M. simiae strains from tap water to which they were routinely exposed.
Conclusions:
This represents an outbreak of M. simiae colonization with one nosocomial infection. It is only the second time that M. simiae has been recovered from hospital tap water and its first presentation in municipal water. This study raises issues about the need and feasibility of eliminating or avoiding exposure to M. simiae from tap water.
To evaluate cost-effective screening and treatment strategies for healthcare workers (HCWs) at risk for tuberculosis exposure.
Design:
A Markov model was developed to track three hypothetical cohorts of HCWs at low, moderate, and high risk for tuberculosis exposure. For those found to be tuberculin reactors at entry, the choice was for isoniazid treatment or no treatment. For those without tuberculin reactivity, the choice of screening intervals was 6 months, 1 year, 2 years, or 5 years. Outcomes measured were tuberculosis cases, death, life expectancy, and cost. Assumptions were derived from published data and analyses.
Results:
Treatment of initial reactors with isoniazid in all three risk groups was associated with a net savings of $14,800 to $15,700 for each tuberculosis case prevented. For those without evidence of infection at entry, the most cost-effective screening interval was 1 year for high-risk groups, 2 years for moderate-risk groups, and 5 years for low-risk groups, with a net savings $0.20 to $26 per HCW per year. Screening at a more frequent interval was still cost-effective.
Conclusions:
For HCWs found to be tuberculin reactors, treatment of their latent infection is to their benefit and is associated with a net cost-savings. Regular tuberculin screening of HCWs can be cost-effective or result in a net cost-savings. Each institution could use its own skin test surveillance data to create an optimum screening program for its employees. However, for most HCWs, a 1-year screening interval would be a cost-effective and safe choice.
To assess the extent of nosocomial transmission of tuberculosis among infants, family members, and healthcare workers (HCWs) who were exposed to a 29-week-old premature infant with congenital tuberculosis, diagnosed at 102 days of age.
Design:
A prospective exposure investigation using tuberculin skin test (TST) conversion was conducted. Contacts underwent two skin tests 10 to 12 weeks apart. Clinical examination and chest radiographs were performed to rule out disease. Isoniazid prophylaxis was administered to exposed infants at higher risk.
Setting:
A neonatal intensive care unit in an urban hospital in Brussels, Belgium.
Participants:
Ninety-seven infants, 139 HCWs, and 180 visitors.
Results:
Newly positive TST results occurred in HCWs who had been in close contact with the infant. Six (19%) of 32 primary care nurses and physicians had TST conversions and received treatment. Among the 97 exposed infants, 85 were screened and 34 were identified as at higher risk of infection. Of these, 27 received preventive isoniazid. None of the infants and none of the 93 other infants' family members evaluated were infected.
Conclusions:
Congenital tuberculosis in an infant poses a risk for nosocomial transmission to HCWs. Delayed diagnosis of this rare disease and close proximity are the most important factors related to transmission.
To determine risk factors for tuberculin skin test (TST) positivity among healthcare workers (HCWs).
Design:
Two-step TST was performed in 2002.
Setting:
Tertiary-care hospital in Ankara, Turkey.
Participants:
A sample of 491 hospital HCWs were included. Information related to demographics, profession, work duration, department, and individual and family history of tuberculosis (TB) was obtained by a structured questionnaire.
Results:
Four hundred eight (83%) had two-step TST positivity. On multivariate analysis, male physicians (relative risk [RR], 1.5; 95% confidence interval [CI95], 1.23–1.69; P = .001), nurses (RR, 1.5; CI95, 1.29–1.66; P = .005), radiology technicians (RR, 1.7; CI95, 1.35–1.73; P = .002), laboratory technicians (RR, 1.6; CI95, 1.3–1.74; P = .007), and male housekeepers (RR, 1.6; CI95, 1.38–1.7; P < .001) had a higher risk than did female physicians. Among laboratory technicians, radiology technicians had the highest TST positivity (85%). HCWs working for less than 1 year (RR, 0.8; CI95, 0.72–0.98; P = .027) had a lower risk of infection. The HCWs having bacille Calmette–Guérin vaccination (RR, 1.12; CI95, 1.08–1.45) had higher TST positivity.
Conclusion:
Male physicians, nurses, and laboratory technicians had increased risk of Mycobacterium tuberculosis infection in this setting, but community exposure likely accounted for most infections.
To determine whether environmental cultures for Legionella increase the index of suspicion for legionnaires' disease (LD).
Design:
Five-year prospective study.
Setting:
Twenty hospitals in Catalonia, Spain.
Methods:
From 1994 to 1996, the potable water systems of 20 hospitals in Catalonia were tested for Legionella, Cases of hospital-acquired LD and availability of an “in-house” Legionella test in the previous 4 years were assessed. After the hospitals were informed of the results of their water cultures, a prospective 5-year-study was conducted focusing on the detection of new cases of nosocomial legionellosis and the availability and use of Legionella testing.
Results:
Before environmental cultures were started, only one hospital had conducted active surveillance of hospital-acquired pneumonia and used Legionella tests including Legionella urinary antigen in all pneumonia cases. Only one other hospital had used the latter test at all. In six hospitals, Legionella tests had been completely unavailable. Cases of nosocomial LD had been diagnosed in the previous 4 years in only two hospitals. During prospective surveillance, 12 hospitals (60%) used Legionella urinary antigen testing in house and 11 (55%) found cases of nosocomial legionellosis, representing 64.7% (11 of 17) of those with positive water cultures. Hospitals with negative water cultures did not find nosocomial LD.
Conclusions:
The environmental study increased the index of suspicion for nosocomial LD. The number of cases of nosocomial LD increased significantly during the prospective follow-up period, and most hospitals began using the Legionella urinary antigen test in their laboratories.
To analyze the efficacy of periodically changing ventilator circuits for decreasing the rate of ventilator-associated pneumonia when a heat and moisture exchanger (HME) is used for humidification. The Centers for Disease Control and Prevention recommended not changing the circuits periodically.
Design:
Randomized, controlled trial conducted between April 2001 and August 2002.
Setting:
A 24-bed, medical–surgical intensive care unit in a 650-bed, tertiary-care hospital.
Patients:
All patients requiring mechanical ventilation during more than 72 hours from April 2001 to August 2002.
Interventions:
Patients were randomized into two groups: (1) ventilation with change of ventilator circuits every 48 hours and (2) ventilation with no change of circuits. Throat swabs were taken on admission and twice weekly until discharge to classify pneumonia as endogenous or exogenous.
Results:
Three hundred four patients (143 from group 1 and 161 from group 2) with similar characteristics (age, gender, Acute Physiology and Chronic Health Evaluation II score, diagnostic group, and mortality) were analyzed. There was no significant difference in the rate of pneumonia between the groups (23.1% vs 23.0% and 15.5 vs 14.8 per 1,000 ventilator-days). There was no significant difference in the incidence of exogenous pneumonia per 1,000 days of mechanical ventilation (1.71 vs 1.25). There was no difference in the distribution of microorganisms causing pneumonia.
Conclusions:
Circuit change using an HME for humidification does not decrease pneumonia and represents an unnecessary cost.