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Cynthia G Whitney

Publications and source records attributed to Cynthia G Whitney.

At least 55 records · Page 3Linked to original sources
PubMed2004

Vaccines as tools against resistance: the example of pneumococcal conjugate vaccine.

Pneumococcal conjugate vaccine not only reduces the incidence of invasive antibiotic-resistant pneumococcal infections in young children receiving the vaccine, but it also reduces transmission of these strains to their younger siblings and to adults. Evidence from the United States indicates that the burden of resistant pneumococcal invasive disease in adults is reduced by immunization of children with these vaccines. Data from Israel and California suggest that antibiotic use is reduced in immunized children, and this reduction in use may further reduce the selection of antibiotic-resistant strains in immunized communities. Surveillance is needed to monitor the spread of antimicrobial resistance into nonvaccine serotypes, which may lead to a resurgence of resistance.

Adult↗
PubMed2004

Activities of cethromycin and telithromycin against recent North American isolates of Streptococcus pneumoniae.

The in vitro activities of two investigational ketolides, cethromycin (formerly ABT-773) and telithromycin, were determined for a selected group of 312 Streptococcus pneumoniae isolates from a national surveillance program. The MIC of cethromycin at which 50% of the isolates were inhibited was 0.008 micro g/ml, and the MIC at which 90% of the isolates were inhibited was 0.06 micro g/ml; the corresponding values for telithromycin were </=0.015 and 0.25 micro g/ml, respectively. For six quinupristin-dalfopristin-resistant strains, the cethromycin MICs were 0.25 to 16 micro g/ml and the telithromycin MICs were 1 to 4 micro g/ml. However, there was only 0.3% resistance to telithromycin.

Anti-Bacterial Agents↗
PubMed2004

Emergence of Streptococcus pneumoniae with very-high-level resistance to penicillin.

Penicillin resistance threatens the treatment of pneumococcal infections. We used sentinel hospital surveillance (1978 to 2001) and population-based surveillance (1995 to 2001) in seven states in the Active Bacterial Core surveillance of the Emerging Infections Program Network to document the emergence in the United States of invasive pneumococcal isolates with very-high-level penicillin resistance (MIC > or = 8 microg/ml). Very-high-level penicillin resistance was first detected in 1995 in multiple pneumococcal serotypes in three regions of the United States. The prevalence increased from 0.56% (14 of 2,507) of isolates in 1995 to 0.87% in 2001 (P = 0.03), with peaks in 1996 and 2000 associated with epidemics in Georgia and Maryland. For a majority of the strains the MICs of amoxicillin (91%), cefuroxime (100%), and cefotaxime (68%), were > or =8 microg/ml and all were resistant to at least one other drug class. Pneumonia (50%) and bacteremia (36%) were the most common clinical presentations. Factors associated with very highly resistant infections included residence in Tennessee, age of <5 or > or =65 years, and resistance to at least three drug classes. Hospitalization and case fatality rates were not higher than those of other pneumococcal infection patients; length of hospital stay was longer, controlling for age. Among the strains from 2000 and 2001, 39% were related to Tennessee(23F)-4 and 35% were related to England(14-)9. After the introduction of the pneumococcal conjugate vaccine, the incidence of highly penicillin resistant infections decreased by 50% among children <5 years of age. The emergence, clonality, and association of very-high-level penicillin resistance with multiple drug resistance requires further monitoring and highlights the need for novel agents active against the pneumococcus.

DNA-Cytosine Methylases↗
PubMed2004

Levofloxacin-resistant invasive Streptococcus pneumoniae in the United States: evidence for clonal spread and the impact of conjugate pneumococcal vaccine.

The emergence of fluoroquinolone resistance in sterile-site isolates of Streptococcus pneumoniae is documented in this study characterizing all invasive levofloxacin-resistant (MIC, > or = 8 mg/liter) S. pneumoniae isolates (n = 50) obtained from the Centers for Disease Control and Prevention Active Bacterial Core Surveillance from 1998 to 2002. Resistance among all isolates increased from 0.1% in 1998 to 0.6% in 2001 (P = 0.008) but decreased to 0.4% in 2002, while resistance among vaccine serotypes continued to increase from 0.3% in 1998 to 1.0% in 2002, suggesting that fluoroquinolones continue to exert selective pressure on these vaccine serotypes. Only 22% of resistant isolates were not covered by the conjugate vaccine serogroups. Multilocus sequence typing revealed that 58% of resistant strains were related to five international clones identified by the Pneumococcal Molecular Epidemiology Network, with the Spain(23F)-1 clone being most frequent (16% of all isolates). Thirty-six percent of the isolates were coresistant to penicillin, 44% were coresistant to macrolides, and 28% were multiresistant to penicillin, macrolides, and fluoroquinolones. Fifty percent of the isolates were resistant to any three drug classes. Ninety-four percent of the isolates had multiple mutations in the quinolone resistance-determining regions of the gyrA, gyrB, parC, and parE genes. In 16% of the isolates, there was evidence of an active efflux mechanism. An unusual isolate was found that showed only a single parE mutation and for which the ciprofloxacin MIC was lower (2 mg/liter) than that of levofloxacin (8 mg/liter). Our results suggest that invasive pneumococcal isolates resistant to levofloxacin in the United States show considerable evidence of multiple resistance and of clonal spread.

Anti-Bacterial Agents↗
PubMed2004

Specificity of the antibody response to the pneumococcal polysaccharide and conjugate vaccines in human immunodeficiency virus-infected adults.

Nonspecific antibodies, which are thought to be nonprotective, have been shown to contribute a substantial proportion of the measured concentration in the standardized immunoglobulin G (IgG) enzyme-linked immunosorbent assay (ELISA) for pneumococcal polysaccharide capsular antibodies. The presence of such antibodies in human immunodeficiency virus (HIV)-infected persons has not been evaluated. The amount of nonspecific antibodies is proportional to the reduction in IgG antibody concentration that occurs with serum absorption with the heterologous polysaccharide 22F. We measured the amount of nonspecific antibodies before and after vaccination with the pneumococcal conjugate vaccine (PCV; n = 33) or the pneumococcal polysaccharide vaccine (PPV; n = 34) in HIV-infected adults with CD4 counts of >/== 200 cells/mm3. Blood was drawn before and 2 months after vaccination. For prevaccination sera, we found a substantial amount of nonspecific antibodies for serotypes 4, 6B, 9V, and 23F (23 to 47% of measured IgG concentration), but not for serotype 14. There tended to be proportionately less nonspecific antibodies in postvaccine sera than prevaccine sera for PCV, but not for PPV. Subjects with a low HIV viral load (</= 400 copies/ml) had proportionately more nonspecific antibodies than those with higher viral load before and after both vaccines. After 22F absorption, the geometric mean concentrations of antibodies were significantly higher post-PCV than post-PPV for the high viral load group for all five serotypes, but for no serotypes in the low viral load group. These findings confirm that absorption with a heterologous pneumococcal polysaccharide (e.g., 22F) is necessary to remove nonspecific antibodies in a standardized IgG ELISA for pneumococcal capsular antibodies in HIV-infected adults.

Adult↗
PubMed2004

Nasopharyngeal versus oropharyngeal sampling for detection of pneumococcal carriage in adults.

Several studies have shown that nasopharyngeal sampling is more sensitive than oropharyngeal sampling for the detection of pneumococcal carriage in children. The data for adults are limited and conflicting. This study was part of a larger study of pneumococcal carriage on the Navajo and White Mountain Apache Reservation following a clinical trial of a seven-valent pneumococcal conjugate vaccine. Persons aged 18 years and older living in households with children enrolled in the vaccine trial were eligible. We collected both nasopharyngeal and oropharyngeal specimens by passing a flexible calcium alginate wire swab either nasally to the posterior nasopharynx or orally to the posterior oropharynx. Swabs were placed in skim milk-tryptone-glucose-glycerin medium and frozen at -70 degrees C. Pneumococcal isolation was performed by standard techniques. Analyses were based on specimens collected from 1,994 adults living in 1,054 households. Nasopharyngeal specimens (11.1%; 95% confidence interval [CI], 9.8 and 12.6%) were significantly more likely to grow pneumococci than were oropharyngeal specimens (5.8%; 95% CI, 4.8 to 6.9%) (P < 0.0001). Few persons had pneumococcal growth from both specimens (1.7%). Therefore, both tests together were more likely to identify pneumococcal carriage (15.2%; 95% CI, 13.7 to 16.9%) than either test alone. Although we found that nasopharyngeal sampling was more sensitive than oropharyngeal sampling, nasopharyngeal sampling alone would have underestimated the prevalence of pneumococcal carriage in this adult population. Sampling both sites may give more accurate results than sampling either site alone in studies of pneumococcal carriage in adults.

Adult↗
PubMed2004

Immunoblot method to detect Streptococcus pneumoniae and identify multiple serotypes from nasopharyngeal secretions.

Conventional culture techniques are limited in the ability to detect multiple Streptococcus pneumoniae serotypes in nasopharyngeal (NP) secretions. We developed an immunoblot (IB) method with monoclonal antibodies (MAbs) to detect S. pneumoniae and to identify serotypes. NP specimens stored in skim milk-tryptone-glucose-glycerol medium were assessed by the IB method and the reference culture method (RM). In the RM, four optochin-sensitive alpha-hemolytic colonies resembling pneumococci were typed by the Quellung reaction. In the IB method, a nitrocellulose membrane blot of surface growth was reacted with a pneumococcal surface adhesion (PsaA) MAb and visualized. Of 47 NP specimens, 32 (68%) were found to be positive and 13 (28%) were found to be negative for pneumococci by both methods; each method alone yielded one positive result. The sensitivity and specificity of the IB method for the detection of pneumococci were 97 and 93%, respectively. To identify serotypes, blots were tested with serotype-specific MAbs (4, 6A, 6B, 9V, 14, 18C, 19F, and 23F). To detect the remaining serotypes, positive serotype-specific replicate blots were compared visually to an original anti-PsaA-positive blot; four unidentified colonies were subcultured and serotyped by the Quellung reaction. Fifty-eight S. pneumoniae-positive NP specimens containing 69 pneumococcal strains (23 serotypes) were tested; 68 (98.6%) of the strains were detected by the IB method, and 66 (95.6%) were detected by the RM. For 11 specimens found to contain two serotypes, both methods detected both serotypes in 7 (63.6%), the IB method alone detected the two serotypes in 3 (27.3%), and the RM alone detected both serotypes in 1 (9%). The IB method identified multiple clones and minor populations of pneumococci in NP secretions. This method is useful for detecting specific serotypes and carriage of multiple serotypes in epidemiologic surveillance and carriage studies.

Antibodies, Bacterial↗
PubMed2004

SARS surveillance during emergency public health response, United States, March-July 2003.

In response to the emergence of severe acute respiratory syndrome (SARS), the United States established national surveillance using a sensitive case definition incorporating clinical, epidemiologic, and laboratory criteria. Of 1,460 unexplained respiratory illnesses reported by state and local health departments to the Centers for Disease Control and Prevention from March 17 to July 30, 2003, a total of 398 (27%) met clinical and epidemiologic SARS case criteria. Of these, 72 (18%) were probable cases with radiographic evidence of pneumonia. Eight (2%) were laboratory-confirmed SARS-coronavirus (SARS-CoV) infections, 206 (52%) were SARS-CoV negative, and 184 (46%) had undetermined SARS-CoV status because of missing convalescent-phase serum specimens. Thirty-one percent (124/398) of case-patients were hospitalized; none died. Travel was the most common epidemiologic link (329/398, 83%), and mainland China was the affected area most commonly visited. One case of possible household transmission was reported, and no laboratory-confirmed infections occurred among healthcare workers. Successes and limitations of this emergency surveillance can guide preparations for future outbreaks of SARS or respiratory diseases of unknown etiology.

Adolescent↗
PubMed2003

Recurrent invasive pneumococcal disease: a population-based assessment.

We sought to define the risk of recurrence of invasive pneumococcal disease (IPD) and to define the characteristics of persons experiencing recurrent IPD through population-based surveillance. Cases of IPD were identified through the US Centers for Disease Control and Prevention's Active Bacterial Core Surveillance. Recurrent episodes were defined as isolation of Streptococcus pneumoniae from any normally sterile site > or =30 days after initial positive culture. Among 13,924 persons who survived their initial episode of IPD, 318 (2.3%) experienced > or =1 subsequent episode, for 376 total recurrences. The recurrence rate was 1294 episodes per 100,000 person-years, or 50 times the annual incidence of IPD. In multivariable analysis, a higher risk of recurrence was seen in persons infected with human immunodeficiency virus and in children <5 years old with chronic illness. Most (92%) persons with recurrence had a vaccine indication. The risk of recurrence among certain persons with IPD is extremely high.

Adolescent↗
PubMed2003

Risk of bacterial meningitis in children with cochlear implants.

BACKGROUND: In June 2002, the Food and Drug Administration received reports of bacterial meningitis in patients with cochlear implants for treatment of hearing loss. Implants that included a positioner (a wedge inserted next to the implanted electrode to facilitate transmission of the electrical signal by pushing the electrode against the medial wall of the cochlea) were voluntarily recalled in the United States in July 2002. METHODS: We identified patients with meningitis and conducted a cohort study and a nested case-control investigation involving 4264 children who had received cochlear implants in the United States between January 1, 1997, and August 6, 2002, and who were less than six years of age when they received the implants. We calculated the incidence of meningitis in the cohort and assessed risk factors for meningitis among patients and among 199 controls, using data from interviews with parents and abstracted from medical records. RESULTS: We identified 26 children with bacterial meningitis. The incidence of meningitis caused by Streptococcus pneumoniae was 138.2 cases per 100,000 person-years--more than 30 times the incidence in a cohort of the same age in the general U.S. population. Postimplantation bacterial meningitis was strongly associated with the use of an implant with a positioner (odds ratio, 4.5 [95 percent confidence interval, 1.3 to 17.9], with adjustment for medical, surgical, and environmental factors) and with the joint presence of radiographic evidence of a malformation of the inner ear and a cerebrospinal fluid leak (adjusted odds ratio, 9.3 [95 percent confidence interval, 1.2 to 94.5]). The incidence of meningitis among patients who had received an implant with a positioner remained higher than the incidence among those whose implants did not have a positioner for the duration of follow-up (24 months from the time of implantation). CONCLUSIONS: Parents and health care providers should ensure that all children who receive cochlear implants are appropriately vaccinated and are then monitored and treated promptly for any bacterial infections after receiving the implant.

Bacterial Vaccines↗
PubMed2003

Effectiveness of the 23-valent polysaccharide vaccine against invasive pneumococcal disease in Navajo adults.

Invasive pneumococcal disease occurs 2-3-fold more often among Navajo adults than among adults in the general United States population. The objective of this observational study was to determine the effectiveness of the 23-valent pneumococcal polysaccharide vaccine (PPV23) among Navajo adults. Active surveillance identified cases of invasive pneumococcal disease during 1996-1997. Three control patients per case patient were matched according to underlying medical conditions, sex, age, and location of medical care. Effectiveness was calculated by regression analysis of case-control sets and by indirect cohort methodology. Diabetes and alcoholism occurred in 41% and 43% of 108 case patients, respectively; 62% of case patients and 64% of control patients were immunized. Overall vaccine effectiveness was 26% (95% confidence interval [CI], -29% to 58%); 15% (95% CI, -116% to 67%) for patients with diabetes and -5% (95% CI, -141% to 54%) for patients with alcoholism. Overall vaccine effectiveness, as determined by use of the indirect cohort methodology, was 35% (95% CI, -33% to 69%). PPV23 was not significantly effective among Navajo adults and may be inadequate to prevent serious pneumococcal disease in this population.

Adult↗
PubMed2003

Cost-effectiveness of vaccination against invasive pneumococcal disease among people 50 through 64 years of age: role of comorbid conditions and race.

BACKGROUND: Guidelines are increasingly recommending preventive services starting at 50 years of age, and policymakers are considering such a recommendation for pneumococcal polysaccharide vaccination. The finding that pneumococcal vaccination is cost-saving for people 65 years of age or older raises the question of the vaccination's implications for other older adults, especially black people, whose disease incidence exceeds that of nonblack people, and those with high-risk conditions. OBJECTIVE: To assess the implications of vaccinating black and nonblack people 50 through 64 years of age against invasive pneumococcal disease. DESIGN: Cost-effectiveness analysis. DATA SOURCES: Published literature for vaccination effectiveness and cost estimates; data on disease incidence and case-fatality rates from the Centers for Disease Control and Prevention. TARGET POPULATION: Hypothetical cohort 50 through 64 years of age with the 1995 U.S. age distribution. TIME HORIZON: Lifetime. PERSPECTIVE: Societal. INTERVENTION: Pneumococcal polysaccharide vaccination compared with no vaccination. OUTCOME MEASURES: Incremental medical costs and health effects, in quality-adjusted life-years per vaccinee. RESULTS OF BASE-CASE ANALYSIS: Vaccination saved medical costs and improved health among high-risk black people (27.55 dollars savings per vaccinee) and nonblack people (5.92 dollars savings per vaccinee), excluding survivors' future costs. For low-risk black and nonblack people and the overall general population, vaccination cost 2477 dollars, 8195 dollars, and 3434 dollars, respectively, to gain 1 year of healthy life. RESULTS OF SENSITIVITY ANALYSIS: Excluding survivors' future costs, in the general immunocompetent population, cost per quality-adjusted life-year in global worst-case results ranged from 21 513 dollars for black people to 68 871 dollars for nonblack people; in the high-risk population, cost ranged from 11 548 dollars for black people to 39 000 dollars for nonblack people. In the global best case, vaccination was cost-saving for black and nonblack people in the general immunocompetent and high-risk populations, excluding survivors' future costs. The cost-effectiveness range was narrower in probabilistic sensitivity analyses, with 95% probabilistic intervals ranging from cost-saving to 1594 dollars for black people and from cost-saving to 12 273 dollars for nonblack people in the general immunocompetent population. Costs per quality-adjusted life-year for low-risk people with case-fatality rates from 1998 were 2477 dollars for black people and 8195 dollars for nonblack people, excluding survivors' medical costs. CONCLUSIONS: These results support the current recommendation to vaccinate high-risk people and provide useful information for considering extending the recommendation to the general population 50 through 64 years of age. Lack of evidence about the effectiveness of revaccination for people 65 years of age or older, when disease risks are higher, argues for further research to guide vaccination policy.

Black or African American↗
PubMed2003

Decline in invasive pneumococcal disease after the introduction of protein-polysaccharide conjugate vaccine.

BACKGROUND: In early 2000, a protein-polysaccharide conjugate vaccine targeting seven pneumococcal serotypes was licensed in the United States for use in young children. METHODS: We examined population-based data from the Active Bacterial Core Surveillance of the Centers for Disease Control and Prevention to evaluate changes in the burden of invasive disease, defined by isolation of Streptococcus pneumoniae from a normally sterile site. Serotyping and susceptibility testing of isolates were performed. We assessed trends using data from seven geographic areas with continuous participation from 1998 through 2001 (population, 16 million). RESULTS: The rate of invasive disease dropped from an average of 24.3 cases per 100,000 persons in 1998 and 1999 to 17.3 per 100,000 in 2001. The largest decline was in children under two years of age. In this group, the rate of disease was 69 percent lower in 2001 than the base-line rate (59.0 cases per 100,000 vs. 188.0 per 100,000, P<0.001); the rate of disease caused by vaccine and vaccine-related serotypes declined by 78 percent (P<0.001) and 50 percent (P<0.001), respectively. Disease rates also fell for adults; as compared with base line, the rate of disease in 2001 was 32 percent lower for adults 20 to 39 years of age (7.6 cases per 100,000 vs. 11.2 per 100,000, P<0.001), 8 percent lower for those 40 to 64 years of age (19.7 per 100,000 vs. 21.5 per 100,000, P=0.03), and 18 percent lower for those 65 years of age or more (49.5 per 100,000 vs. 60.1 per 100,000, P<0.001). The rate of disease caused by strains that were not susceptible to penicillin was 35 percent lower in 2001 than in 1999 (4.1 cases per 100,000 vs. 6.3 per 100,000, P<0.001). CONCLUSIONS: The use of the pneumococcal conjugate vaccine is preventing disease in young children, for whom the vaccine is indicated, and may be reducing the rate of disease in adults. The vaccine provides an effective new tool for reducing disease caused by drug-resistant strains.

Adolescent↗
PubMed2003

An outbreak of conjunctivitis due to atypical Streptococcus pneumoniae.

BACKGROUND: In February 2002, clinicians at the Dartmouth College Health Service recognized an outbreak of conjunctivitis; cultures of conjunctival swabs implicated Streptococcus pneumoniae. An investigation was begun to determine the extent of the outbreak, confirm the cause, identify modes of transmission, and implement control measures. METHODS: Investigators reviewed the health service's data base for diagnoses of conjunctivitis. Viral and bacterial cultures were obtained from ill students. Bile-soluble isolates that were susceptible to ethylhydrocupreine (optochin) and therefore were presumed to be pneumococci underwent serotyping, capsular staining, pulsed-field gel electrophoresis, a DNA probe, and multilocus sequence typing. A cohort study of risk factors was conducted with the use of the Internet. Control measures included distribution of alcohol-based hand gel and messages about prevention. RESULTS: Among 5060 students, 698 (13.8 percent) received a diagnosis of conjunctivitis from January 1, 2002, through April 12, 2002, including 22 percent of first-year students. Presumed pneumococci were isolated from 43.3 percent of conjunctival swabs (110 of 254); viral cultures performed on 85 specimens were negative. DNA probes and multilocus sequence typing confirmed that the organisms were pneumococci, although the bacteria did not have the characteristic capsule. On pulsed-field gel electrophoresis, strains were found to be identical to pneumococci that caused outbreaks of conjunctivitis in other parts of the country in 1980. Analysis of survey data from 1832 students indicated that close contact with a student with conjunctivitis, wearing contact lenses, membership on a sports team, and attending parties at or living in a fraternity or sorority house were associated with conjunctivitis. The rate of diagnosis of conjunctivitis declined after the implementation of control measures and after spring break. CONCLUSIONS: This large outbreak of conjunctivitis on a college campus was caused by an atypical, unencapsulated strain of S. pneumoniae that was identical to strains that had caused outbreaks two decades earlier.

Conjunctiva↗
PubMed2003

Geographic diversity and temporal trends of antimicrobial resistance in Streptococcus pneumoniae in the United States.

Resistance of Streptococcus pneumoniae to antibiotics is increasing throughout the United States, with substantial variation among geographic regions. We show that patterns of geographic variation are best explained by the intensity of selection for resistance, which is reflected by differences between the proportions of resistance within individual serotypes, rather than by differences between the frequencies of particular serotypes. Using a mathematical transmission model, we analyzed temporal trends in the proportions of singly and dually resistant organisms and found that pneumococcal strains resistant to both penicillin and erythromycin are increasing faster than strains singly resistant to either. Using the model, we predict that by 1 July 2004, in the absence of a vaccine, 41% of pneumococci at the Centers for Disease Control and Prevention (CDC)'s Active Bacterial Core surveillance (ABCs) sites, taken together, will be dually resistant, with 5% resistant to penicillin only and 5% to erythromycin only.

Drug Resistance↗
PubMed2003

Invasive pneumococcal disease in older adults residing in long-term care facilities and in the community.

OBJECTIVES: To examine the epidemiology of invasive pneumococcal disease in older adults hospitalized for invasive pneumococcal disease who are living in the community and in long-term care facilities (LTCFs) in the United States. DESIGN: Analysis of 2402 cases of invasive pneumococcal disease requiring hospitalization in 2000 and 2001 that the Centers for Disease Control and Prevention's Active Bacterial Core Surveillance collected in nine states. SETTING: Hospital. PARTICIPANTS: Hospitalized LTCF residents and community-living older adults in the United States. MEASUREMENTS: Age- and residence-specific pneumococcal disease incidence rates per 100000 persons, case-fatality rates, and trends in antimicrobial resistance. RESULTS: Nationally, the rate of invasive pneumococcal disease in LTCF residents was 194.2 cases per 100000 persons aged 65 and older and 44.6 for community-living older adults (relative risk=4.4, 95% confidence interval (CI)=4.2-4.5). Compared with community-living older adults, case-fatality rates were 1.9 times higher (30.8% vs 16.0%, 95% CI=1.5-2.5). Pneumococcal strains from LTCF residents were significantly more likely to be nonsusceptible to levofloxacin than strains from community- living older adults (5.7% vs 0.4%, P<.001). CONCLUSION: Older adults living in LTCFs are at a higher risk for invasive pneumococcal disease and death than are community-living older adults. Additionally, fluoroquinolone resistance is significantly higher in older adults living in LTCFs and may provide clues to emerging antimicrobial resistance in the general population.

Aged↗
PubMed2003

Risk of hospital-acquired legionnaires' disease in cities using monochloramine versus other water disinfectants.

OBJECTIVE: To measure the association between the disinfection of municipal drinking water with monochloramine and the occurrence of hospital-acquired legionnaires' disease (LD). SETTING: One hundred sixty-six U.S. hospitals. DESIGN: Survey of 459 members of the Society for Healthcare Epidemiology of America (SHEA) for hospital features; endemic- and outbreak-related, hospital-acquired LD; the source of the hospital water supply; and the methods of disinfection used by the hospitals and municipal water treatment plants. RESULTS: SHEA members representing 166 (36%) of 459 hospitals responded; 33 (20%) reported one or more episodes of hospital-acquired LD during the period from 1994 to 1998 and 23 (14%) reported an outbreak of hospital-acquired LD during the period from 1989 to 1998. Hospitals with an occurrence of hospital-acquired LD had a higher census (median, 319 vs 221; P = .03), more acute care beds (median, 500 vs 376; P = .04), and more intensive care unit beds (median, 42 vs 24; P = .009) than did other hospitals. They were also more likely to have a transplant service (74% vs 42%; P = .001) and to perform surveillance for hospital-acquired disease (92% vs 61%; P = .001). After adjustment for the presence of a transplant program and surveillance for legionnaires' disease, hospitals supplied with drinking water disinfected with monochloramine by municipal plants were less likely to have sporadic cases or outbreaks of hospital-acquired LD (odds ratio, 0.20; 95% confidence interval, 0.07 to 0.56) than were other hospitals. CONCLUSION: Water disinfection with monochloramine by municipal water treatment plants significantly reduces the risk of hospital-acquired LD.

American Hospital Association↗