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J C Butler

Publications and source records attributed to J C Butler.

At least 37 records · Page 2Linked to original sources
PubMed1999

Hospital characteristics associated with colonization of water systems by Legionella and risk of nosocomial legionnaires' disease: a cohort study of 15 hospitals.

OBJECTIVE: To investigate an increase in reports of legionnaires' disease by multiple hospitals in San Antonio, Texas, and to study risk factors for nosocomial transmission of legionnaires' disease and determinants for Legionella colonization of hospital hot-water systems. SETTING: The 16 largest hospitals in the cities of San Antonio, Temple, and Austin, Texas. DESIGN: Review of laboratory databases to identify patients with legionnaires' disease in the 3 years prior to the investigation and to determine the number of diagnostic tests for Legionella performed; measurement of hot-water temperature and chlorine concentration and culture of potable water for Legionella. Exact univariate calculations, Poisson regression, and linear regression were used to determine factors associated with water-system colonization and transmission of Legionella. RESULTS: Twelve cases of nosocomial legionnaires' disease were identified; eight of these occurred in 1996. The rise in cases occurred shortly after physicians started requesting Legionella urinary antigen tests. Hospitals that frequently used Legionella urinary antigen tests tended to detect more cases of legionnaires' disease. Legionella was isolated from the water systems of 11 of 12 hospitals in San Antonio; the 12th had just experienced an outbreak of legionnaires' disease and had implemented control measures. Nosocomial legionellosis cases probably occurred in 5 hospitals. The number of nosocomial legionnaires' disease cases in each hospital correlated better with the proportion of water-system sites that tested positive for Legionella (P=.07) than with the concentration of Legionella bacteria in water samples (P=.23). Hospitals in municipalities where the water treatment plant used monochloramine as a residual disinfectant (n=4) and the hospital that had implemented control measures were Legionella-free. The hot-water systems of all other hospitals (n=11) were colonized with Legionella. These were all supplied with municipal drinking water that contained free chlorine as a residual disinfectant. In these contaminated hospitals, the proportion of sites testing positive was inversely correlated with free residual chlorine concentration (P=.01). In all hospitals, hot-water temperatures were too low to inhibit Legionella growth. CONCLUSIONS: The increase in reporting of nosocomial legionnaires' disease was attributable to increased use of urinary antigen tests; prior cases may have gone unrecognized. Risk of legionnaires' disease in hospital patients was better predicted by the proportion of water-system sites testing positive for Legionella than by the measured concentration of Legionella bacteria. Use of monochloramine by municipalities for residual drinking water disinfection may help prevent legionnaires' disease.

Cohort Studies↗
PubMed1999

A survey of methods used to detect nosocomial legionellosis among participants in the National Nosocomial Infections Surveillance System.

OBJECTIVE: To help define the scope of nosocomial legionnaire's disease (LD) and to assess use of recommended diagnostic methods and transmission control practices. METHODS: We surveyed 253 hospitals participating in the National Nosocomial Infections Surveillance (NNIS) System. The anonymous survey included questions about episodes of nosocomial LD, environmental sampling practices, maintenance of hospital water systems, and diagnostic techniques. RESULTS: Of 192 hospitals that responded, 29% reported at least one episode of nosocomial LD from 1990 through 1996, and 61% of these reported at least two episodes. Of 79 hospitals with transplant programs, 42% reported nosocomial LD, compared with 20% of hospitals without transplant programs. Environmental sampling had been conducted by 55% of hospitals, including 79% of those reporting nosocomial LD. Legionella were isolated in 34% that sampled potable water and 19% that sampled cooling system reservoirs. Supplemental potable-water decontamination systems were installed in 20% of hospitals. Only 19% routinely performed testing for legionellosis among patients at high risk for nosocomial LD. CONCLUSIONS: Nosocomial LD is relatively common among NNIS hospitals, especially those performing organ transplants. Environmental sampling for Legionella is a common practice among NNIS hospitals, and Legionella often are isolated from sampled hospital cooling towers and hospital potable-water systems. Hospitals have responded to suspected nosocomial LD infection with a variety of water sampling and control strategies; some have not attempted to sample or decontaminate water systems despite identified transmission.

Adult↗
PubMed1999

Pneumococcal drug resistance: the new "special enemy of old age".

Streptococcus pneumoniae is a leading cause of illness and death among the elderly. The recent emergence of drug-resistant strains has complicated selection of antimicrobial therapy for suspected pneumococcal infections. In some areas of North America, nearly 40% of pneumococcal isolates from the blood or cerebrospinal fluid of persons > or = 65 years old had reduced susceptibility to penicillin. Of all penicillin-resistant infections, >30% occur in persons > or = 65 years old. The increasing prevalence of drug-resistant pneumococci and recent outbreaks of pneumococcal disease in chronic-care facilities emphasize the importance of efforts to prevent these infections in the elderly. Limiting selection for drug-resistant strains through judicious use of antimicrobial drugs and preventing invasive pneumococcal infections through increased use of pneumococcal vaccine form the foundation of these efforts.

Aged↗
PubMed1999

Epidemiology of pneumococcal infections in the elderly.

The risk of invasive Streptococcus pneumoniae infection (primarily bacteraemia and meningitis) is greatest among the very young and the very old. Persons in certain racial groups, including African-Americans, American Indians, Native Alaskans and Australian Aborigines, are also at increased risk of disease. Other factors that appear to increase the risk of pneumococcal infection are lower socioeconomic status, recent infection with influenza and possibly other viral respiratory tract infections, chronic medical conditions, and immunosuppressive medications. Reported annual incidences of invasive pneumococcal disease among persons aged > or = 65 years in North America and Europe range from 25 to 90 cases/100,000 persons. In the US and Canada, these rates represent between 15,000 and 30,000 cases annually among the elderly. Mortality caused by pneumococcal infections is highest among the elderly, with nearly 1 in 5 cases resulting in death. Worldwide, S. pneumoniae is the leading cause of community-acquired pneumonia requiring hospitalisation. The high fatality rates, as well as recent outbreaks of pneumococcal infection among unvaccinated nursing home residents and the emergence of drug-resistant pneumococcal strains, highlight the importance of preventing invasive infection by vaccination.

Aged↗
PubMed1999

Acute otitis media: management and surveillance in an era of pneumococcal resistance. Drug-Resistant Streptococcus Pneumoniae Therapeutic Working Group.

Experts in the management of otitis media and the Drug-resistant Streptococcus pneumoniae Therapeutic Working Group were convened by the Centers for Disease Control and Prevention to respond to changes in antimicrobial susceptibility among pneumococci. The objective was to provide consensus recommendations for the management of acute otitis media (AOM) and for the surveillance of drug-resistant Streptococcus pneumoniae. After summarizing published and unpublished data from the scientific literature and the experience of the panel members, the group concluded that oral amoxicillin should remain the first-line antimicrobial agent for treating AOM. For patients with clinically defined treatment failure after 3 days of therapy, useful alternative agents include amoxicillin-clavulanate, cefuroxime axetil, and intramuscular ceftriaxone. The group also made recommendations to improve surveillance and to obtain antimicrobial susceptibility patterns for local geographic areas.

Acute Disease↗
PubMed1999

Acute otitis media: management and surveillance in an era of pneumococcal resistance--a report from the Drug-resistant Streptococcus pneumoniae Therapeutic Working Group.

OBJECTIVE: To provide recommendations [corrected] for the management of acute otitis media (AOM) and the surveillance of drug-resistant Streptococcus pneumoniae (DRSP). Five questions were addressed: (1) Can amoxicillin remain the best initial antimicrobial agent for treating AOM in the current period of increasing prevalence of DRSP? (2) What are suitable alternative agents for use if amoxicillin fails? (3) Should empiric treatment of AOM vary by geographic region? (4) Where can clinicians learn about resistance patterns in their patient populations? (5) What modifications to laboratory surveillance would improve the utility of the information for clinicians treating AOM? PARTICIPANTS: Experts in the management of otitis media and the DRSP Therapeutic Working Group. This group was convened by the CDC to respond to changes in antimicrobial susceptibility among pneumococci and includes clinicians, academicians and public health practitioners. EVIDENCE: Published and unpublished data summarized from the scientific literature and experience from the experts present. PROCESS: [corrected] After group presentations and review of background materials, subgroup chairs prepared draft responses to the five questions, discussed the responses as a group and edited those responses [corrected]. CONCLUSIONS: Oral amoxicillin should remain the first line antimicrobial agent for treating AOM. In view of the increasing prevalence of DRSP, the safety of amoxicillin at higher than standard dosages and evidence that higher dosages of amoxicillin can achieve effective middle ear fluid concentrations, an increase in the dosage used for empiric treatment from 40 to 45 mg/kg/day to 80 to 90 mg/kg/day is recommended. For patients with clinically defined treatment failure after 3 days of therapy, useful alternative agents include oral amoxicillin-clavulanate, cefuroxime axetil and intramuscular ceftriaxone. Many of the 13 other Food and Drug Administration-approved otitis media drugs lack good evidence for efficacy against DRSP. Currently local surveillance data for pneumococcal resistance that are relevant for the clinical management of AOM are not available from most areas in the United States. Recommendations to improve surveillance include establishing criteria for setting susceptibility breakpoints for clinically appropriate antimicrobials to ensure relevance for treating AOM, testing middle ear fluid or nasal swab isolates in addition to sterile site isolates and testing of drugs that are useful in treating AOM. The management of otitis media has entered a new era with the development of DRSP. These recommendations are intended to provide a framework for appropriate clinical and public health responses to this problem.

Acute Disease↗
PubMed1998

An outbreak of multidrug-resistant pneumococcal pneumonia and bacteremia among unvaccinated nursing home residents.

BACKGROUND: Outbreaks of pneumococcal disease are uncommon and have occurred mainly in institutional settings. Epidemic, invasive, drug-resistant pneumococcal disease has not been seen among adults in the United States. In February 1996, there was an outbreak of multidrug-resistant pneumococcal pneumonia among the residents of a nursing home in rural Oklahoma. METHODS: We obtained nasopharyngeal swabs for culture from residents and employees. Streptococcus pneumoniae isolates were serotyped and compared by pulsed-field gel electrophoresis. A retrospective cohort study was conducted to identify factors associated with colonization and disease. RESULTS: Pneumonia developed in 11 of 84 residents (13 percent), 3 of whom died. Multidrug-resistant S. pneumoniae, serotype 23F, was isolated from blood and sputum from 7 of the 11 residents with pneumonia (64 percent) and from nasopharygeal specimens from 17 of the 74 residents tested (23 percent) and 2 of the 69 employees tested (3 percent). All the serotype 23F isolates were identical according to pulsed-field gel electrophoresis. Recent use of antibiotics was associated with both colonization (relative risk, 2.3; 95 percent confidence interval, 1.3 to 4.2) and disease (relative risk, 3.6; 95 percent confidence interval, 1.2 to 10.8). Only three residents (4 percent) had undergone pneumococcal vaccination. After residents received pneumococcal vaccine and prophylactic antibiotics, there were no additional cases of pneumonia, and the rates of carriage decreased substantially. CONCLUSIONS: In this outbreak a single pneumococcal strain was disseminated among the residents and employees of a nursing home. The high prevalence of colonization with a virulent organism in an unvaccinated population contributed to the high attack rate. Clusters of pneumococcal disease may be underrecognized in nursing homes, and wider use of pneumococcal vaccine is important to prevent institutional outbreaks of drug-resistant S. pneumoniae infection.

Adult↗
PubMed1998

Epidemiology of emerging pneumococcal drug resistance: implications for treatment and prevention.

Drug-resistant Streptococcus pneumoniae infection are becoming increasingly common throughout the world. These strains pose new challenges in the treatment of suspected pneumococcal infections, and they highlight the importance of limiting selection for resistant strains through judicious antibiotic use and preventing infection by immunization of persons at high risk. The clinical impact of drug-resistant S. pneumoniae infection has not been fully defined, but anecdotal reports suggest that outcome is poor for persons with drug-resistant pneumococcal meningitis. The American Academy of Pediatrics has recommended adding vancomycin to the treatment of suspected pneumococcal meningitis cases until the results of culture and susceptibility testing are available. Additional data are needed to determine the optimal empiric antibiotic regimen for nonmeningeal invasive pneumococcal infections. A 23-valent pneumococcal capsular polysaccharide vaccine can prevent many drug-resistant and susceptible invasive pneumococcal infections. The vaccine is recommended in the United States for persons at increased risk of pneumococcal infection due to certain medical conditions and for all persons > or = 65 years old. Vaccine efficacy for immunocompetent persons > or = 65 years is 75%. However, the vaccine is underutilized, and a substantial reduction in the morbidity and mortality associated with invasive pneumococcal infections is unlikely until the vaccine is used more widely among persons at risk for disease.

Adolescent↗
PubMed1998

Epidemic Legionnaires' disease two decades later: old sources, new diagnostic methods.

In July 1995 we investigated a pneumonia outbreak in a Pennsylvania town. We conducted epidemiological and molecular microbiological studies to determine the outbreak source and interrupt transmission of disease. Legionnaires' disease (LD) was quickly identified by urine antigen testing, and a newly developed immunohistochemical stain confirmed nosocomial transmission to a hospital inpatient. LD was confirmed in 22 patients. Case-patients were more likely than controls to have been within 1,000 feet of the hospital (matched odds ratio, 21.0; 95% confidence interval, 2.9-368) during the 2 weeks prior to illness. Legionella pneumophila serogroup 1 (Lp-1) was isolated from hospital cooling towers (CTs) and rooftop air samples but not from hospital potable water or community CTs. Hospital CT and air Lp-1 isolates matched all five patient isolates by monoclonal antibody, arbitrarily primed polymerase chain reaction, and pulsed-field gel electrophoresis subtyping. Strategies to prevent LD must include minimizing transmission from CTs.

Adult↗
PubMed1998

Detection of chlamydiosis in a shipment of pet birds, leading to recognition of an outbreak of clinically mild psittacosis in humans.

Avian chlamydiosis was detected in a shipment of > 700 pet birds from a Florida bird distributor that were sold to nine Atlanta-area pet stores in August 1995. Respiratory illness among persons who had recently acquired birds from this shipment was reported to local public health officials. The attack rate of acute respiratory illness was 10.7% among persons in households exposed to birds from the implicated flock vs. 1.8% among control households (odds ratio, 6.60; 95% confidence interval, 1.39-31.2). Illness and serological evidence of infection in the absence of symptoms were more common among persons in households with recently purchased birds that were sick or that had died and among persons who had had direct contact with the birds. Clinical psittacosis or serological evidence of Chlamydia psittaci infection was found in 30.7% of households with birds from the infected flock. Mild illnesses and asymptomatic infections in exposed persons were unusual features of this outbreak.

Animals↗
PubMed1998

More than 10 years of unrecognized nosocomial transmission of legionnaires' disease among transplant patients.

OBJECTIVE: To investigate a cluster of cases of legionnaires' disease among patients at a hospital. SETTING: A university hospital that is a regional transplant center. DESIGN: Retrospective review of microbiology and serology data from the hospital laboratories and prospective surveillance via the radiology department; a case-control study and environmental sampling within the hospital and from nearby cooling towers. RESULTS: Diagnosis of seven cases of legionnaires' disease in the first 9 months of 1996 led to recognition of a nosocomial outbreak that may have begun as early as 1979. Review of charts from 1987 through September 1996 identified 25 culture-confirmed cases of nosocomial or possibly nosocomial legionnaires' disease, including 18 in bone marrow and heart transplant patients. Twelve patients (48%) died. During the first 9 months of 1996, the attack rate was 6% among cardiac and bone marrow transplant patients. For cases that occurred before 1996, intubation was associated with increased risk for disease. High-dose corticosteroid medication was strongly associated with the risk for disease, but other immunosuppressive therapy or cancer chemotherapy was not. Several species and serogroups of Legionella were isolated from numerous sites in the hospital's potable water system. Six of seven available clinical isolates were identical and were indistinguishable from environmental isolates by pulsed-field gel electrophoresis. Initial infection control measures failed to interrupt nosocomial acquisition of infection. After extensive modifications to the water system, closely monitored repeated hyperchlorinations, and reduction of patient exposures to aerosols, transmission was interrupted. No cases have been identified since September 1996. CONCLUSIONS: Legionella can colonize hospital potable water systems for long periods of time, resulting in an ongoing risk for patients, especially those who are immunocompromised. In this hospital, nosocomial transmission possibly occurred for more than 17 years and was interrupted in 1996, after a sudden increase in incidence led to its recognition. Hospitals specializing in the care of immunocompromised patients (eg, transplant centers) should prioritize surveillance for cases of legionnaires' disease. Aggressive control measures can interrupt transmission of this disease successfully.

Case-Control Studies↗
PubMed1998

The use of Streptococcus pneumoniae nasopharyngeal isolates from healthy children to predict features of invasive disease.

BACKGROUND: The role of sampling nasopharyngeal carriage isolates of Streptococcus pneumoniae to determine characteristics of isolates causing invasive disease has not been established. METHODS: Data were compared from two 1995 studies of S. pneumoniae in Metropolitan Toronto and Peel Region (population, 3.1 million). The first was a prospective survey of nasopharyngeal (NP) carriage in child care centers. The second was a prospective surveillance for all cases of invasive disease. RESULTS: There were 545 NP S. pneumoniae isolates obtained from 532 children and 96 cases of invasive S. pneumoniae disease in children. The prevalences of reduced antibiotic susceptibility in the NP carriage and invasive studies, respectively, were: penicillin (16% vs. 11%, P=0.29); erythromycin (12% vs. 7%, P=0.25); and multiresistant (16% vs. 12%, P=0.34). The power to rule out a difference between the groups was <30% for each comparison. Trimethoprim/sulfamethoxazole resistance was more common in NP carriage isolates than invasive isolates (38% vs. 23%, P=0.02). Serotype 14 was more common in invasive isolates, whereas serogroup 6 was more common in NP carriage isolates. Antibiotic-resistant isolates were predominantly serogroups 6, 19 and 23 in both studies. CONCLUSIONS: Nasopharyngeal carriage isolates of S. pneumoniae reflect the antibiotic susceptibility rates of invasive isolates found in the same period for most antibiotics. However, even a large study like this may have limited power to detect a difference. The most common NP carriage serotypes are the same as the invasive isolates, although the rank order of specific serotypes is different. Routine surveys of S. pneumoniae NP carriage are not feasible because of the cost of serotyping and limited power of the observations, unless sample sizes are extremely large.

Age Factors↗
PubMed1998

Legionnaires' disease: clinical, epidemiological, and public health perspectives.

Legionnaires' disease is a modern environmental infectious disease. It stems from the capacity of the causative agent, Legionella, to multiply within amoebae in warm water and the use, during the 20th century, of devices that maintain water at warm temperatures and produce aerosols. When contaminated with Legionella, aerosols consisting of respirable droplets place the bacteria in juxtaposition with alveolar macrophages, which, as with amoebae, they may parasitize, resulting in illness in susceptible persons. The disease is much more common than previously appreciated with at least 13,000 cases estimated to occur per year in the United States, based on prospective studies. Two highly specific tests, urinary antigen detection and sputum culture, are available for diagnosis during illness. With 60% to 80% sensitivity, urinary antigen tests rapidly detect antigens of Legionella pneumophila serogroup 1, which are responsible for 70% of the cases of legionnaires' disease; results can be available within a few hours. Culture of sputum is 50% to 60% sensitive, but several days are required for growth, and many patients do not produce sputum. Serologic testing, although useful for epidemiologic studies when convalescent-phase antibody titers can be compared with acute-phase titers, is not helpful for clinical decision making because of the low positive predictive value of commercially available acute-phase serologic tests. Erythromycins, intravenous azithromycin, and levofloxacin are currently approved by the US Food and Drug Administration for treatment of legionnaires' disease. However, clarithromycin and several other fluoroquinolones are active against Legionella and may also provide effective therapy. Recent recommendations from the Centers for Disease Control and Prevention's Hospital Infection Control Practices Advisory Committee should be helpful in reducing nosocomial legionnaires' disease. Recommendations are in place or are being developed to minimize the risk of disease in a variety of other settings.

Communicable Disease Control↗
PubMed1998

A recurrent outbreak of nosocomial legionnaires' disease detected by urinary antigen testing: evidence for long-term colonization of a hospital plumbing system.

BACKGROUND: In 1994, a hospital reported an increase in nosocomial legionnaires' disease after implementing use of a rapid urinary antigen test for Legionella pneumophila serogroup 1 (Lp-1). This hospital was the site of a previous nosocomial legionnaires' disease outbreak during 1980 to 1982. METHODS: Infection control records were reviewed to compare rates of nosocomial pneumonia and the proportion of cases attributable to legionnaires' disease during the 1994 outbreak period with those during the same period in 1993. Water samples were collected for Legionella culture from the hospital's potable water system and cooling towers, and isolates were subtyped by monoclonal antibody (MAb) testing and arbitrarily primed polymerase chain reaction (AP-PCR). RESULTS: Nosocomial pneumonia rates were similar from April through October 1993 and April through October 1994: 5.9 and 6.6 per 1,000 admissions, respectively (rate ratio [RR], 1.1; P=.56); however, 3.2% of nosocomial pneumonias were diagnosed as legionnaires' disease in 1993, compared with 23.9% in 1994 (RR, 9.4; P<.001). In 1994, most legionnaires' disease cases were detected by the urinary antigen testing alone. MAb testing and AP-PCR demonstrated identical patterns among Lp-1 isolates recovered from a patient's respiratory secretions, the hospital potable water system, and stored potable water isolates from the 1980 to 1982 outbreak. CONCLUSIONS: There may have been persistent transmission of nosocomial legionnaires' disease at this hospital that went undiscovered for many years because there was no active surveillance for legionnaires' disease. Introduction of a rapid urinary antigen test improved case ascertainment. Legionella species can be established in colonized plumbing systems and may pose a risk for infection over prolonged periods.

Connecticut↗