Development and Evaluation of Statewide Prospective Spatiotemporal Legionellosis Cluster Surveillance, New Jersey, USA.

Incidence of Legionnaires' disease is increasing, particularly in the Mid-Atlantic states in the United States; since 2015, New Jersey has documented ≈250-350 legionellosis cases per year. We used SaTScan software to develop a semiautomated surveillance tool for prospectively detecting legionellosis clusters in New Jersey. We varied temporal window size and baseline period to evaluate optimal parameter selections. The surveillance system detected 3 community clusters of Legionnaires' disease that were subsequently investigated. Other, smaller clusters were detected, but standard epidemiologic data did not identify common sources or new cases. The semiautomated processing is straightforward and replicable in other jurisdictions, likely by persons with even basic programming skills.

Analysis of population-level determinants of legionellosis: spatial and geovisual methods for enhancing classification of high-risk areas.

BACKGROUND: Although the incidence of legionellosis throughout North America and Europe continues to increase, public health investigations have not been able to identify a common exposure in most cases. Over 80% of cases are sporadic with no known source. To better understand the role of the macro-environment in legionellosis risk, a retrospective ecological study assessed associations between population-level measures of demographic, socioeconomic, and environmental factors and high-risk areas. METHODS: Geographic variability and clustering of legionellosis was explored in our study setting using the following methods: unadjusted and standardized incidence rate and SaTScan™ cluster detection methods using default scanning window of 1 and 50% as well as a reliability score methodology. Methods for classification of "high-risk" census tracts (areas roughly equivalent to a neighborhood with average population of 4000) for each of the spatial methods are presented. Univariate and multivariate logistic regression analyses were used to estimate associations with sociodemographic factors: population ≥ 65 years of age, non-white race, Hispanic ethnicity, poverty, less than or some high school education; housing factors: housing vacant, renter-occupied, and built pre-1950 and pre-1970; and whether drinking water is groundwater or surface water source. RESULTS: Census tracts with high percentages of poverty, Hispanic population, and non-white population were more likely to be classified as high-risk for legionellosis versus a low-risk census tract. Vacant housing, renter-occupied housing, and homes built pre-1970 were also important positively associated risk factors. Drinking water source was not found to be associated with legionellosis incidence. DISCUSSION: Census tract level demographic, socioeconomic, and environmental characteristics are important risk factors of legionellosis and add to our understanding of the macro-environment for legionellosis occurrence. Our findings can be used by public health professionals to target disease prevention communication to vulnerable populations. Future studies are needed to explore the exact mechanisms by which these risk factors may influence legionellosis clustering.

Associations of household factors, hot water temperature, and chlorine residual with Legionella occurrence in single-family homes in New Jersey.

Only 4 % of reported Legionnaires' disease (LD) cases are outbreak-associated and the remaining 96 % are sporadic, for which no known source of Legionella is identified. Although outbreaks of LD are linked to cooling towers, decorative fountains, spas and hot tubs, and other sources, the drivers of sporadic LD are less known. Residential premise plumbing is likely an important source of aerosol exposure and there are unique features of premise plumbing which could lead to proliferation of Legionella. A sampling study of Legionella in single-family homes was undertaken in NJ from 2020 to 2021 which included a household characteristic survey and collection of hot water temperature and chlorine residual during sampling. A total of 94 homeowners residing in owner-occupied, single-family units with individual hot water systems were recruited to participate through two mechanisms (1) Legionnaire's disease case-patients and (2) non-case volunteers from each NJ county. Among the 94 single-family homes sampled, 15 % had least one sample positive for Legionella by culture and 57 % had at least one sample with detection of Legionella DNA markers by PCR. Chlorine residual, hot water temperature, and season were independently associated with increased detection of Legionella in home water samples. There was limited or inconsistent evidence of the role of household characteristic factors in Legionella detection. This study identified season, insufficient chlorine residual and hot water temperature as risk factors for Legionella detection in single-family homes. Findings from this work can promote additional partnership between public health and water utilities in improving chlorine residuals in residential communities and educating homeowners on best practices for home water management.

Bacterial septic arthritis infections associated with intra-articular injection practices for osteoarthritis knee pain-New Jersey, 2017.

BACKGROUND: In March 2017, the New Jersey Department of Health received reports of 3 patients who developed septic arthritis after receiving intra-articular injections for osteoarthritis knee pain at the same private outpatient facility in New Jersey. The risk of septic arthritis resulting from intra-articular injection is low. However, outbreaks of septic arthritis associated with unsafe injection practices in outpatient settings have been reported. METHODS: An infection prevention assessment of the implicated facility's practices was conducted because of the ongoing risk to public health. The assessment included an environmental inspection of the facility, staff interviews, infection prevention practice observations, and a medical record and office document review. A call for cases was disseminated to healthcare providers in New Jersey to identify patients treated at the facility who developed septic arthritis after receiving intra-articular injections. RESULTS: We identified 41 patients with septic arthritis associated with intra-articular injections. Cultures of synovial fluid or tissue from 15 of these 41 case patients (37%) recovered bacteria consistent with oral flora. The infection prevention assessment of facility practices identified multiple breaches of recommended infection prevention practices, including inadequate hand hygiene, unsafe injection practices, and poor cleaning and disinfection practices. No additional cases were identified after infection prevention recommendations were implemented by the facility. DISCUSSION: Aseptic technique is imperative when handling, preparing, and administering injectable medications to prevent microbial contamination. CONCLUSIONS: This investigation highlights the importance of adhering to infection prevention recommendations. All healthcare personnel who prepare, handle, and administer injectable medications should be trained in infection prevention and safe injection practices.

Outbreak of bacterial endocarditis associated with an oral surgery practice: New Jersey public health surveillance, 2013 to 2014.

BACKGROUND: In October and November 2014, the New Jersey Department of Health received reports of 3 patients who developed Enterococcus faecalis endocarditis after undergoing surgical procedures at the same oral surgery practice in New Jersey. Bacterial endocarditis is an uncommon but life-threatening condition; 3 patients with enterococcal endocarditis associated with a single oral surgery practice is unusual. An investigation was initiated because of the potential ongoing public health risk. METHODS: Public health officials conducted retrospective surveillance to identify additional patients with endocarditis associated with the practice. They interviewed patients using a standardized questionnaire. An investigative public health team inspected the office environment, interviewed staff, and reviewed medical records. RESULTS: Public health officials identified 15 confirmed patients with enterococcal endocarditis of those patients who underwent procedures from December 2012 through August 2014. Among these patients, 12 (80%) underwent cardiac surgery. One (7%) patient died from complications of endocarditis and subsequent cardiac surgery. Breaches of recommended infection prevention practices were identified that might have resulted in transmission of enterococci during the administration of intravenous sedation, including failure to perform hand hygiene and failure to maintain aseptic technique when performing procedures and handling medications. CONCLUSIONS: This investigation highlights the importance of adhering to infection prevention recommendations in dental care settings. No additional patients with endocarditis were identified after infection prevention and control recommendations were implemented. PRACTICAL IMPLICATIONS: Infection prevention training should be emphasized at all levels of professional dental training. All dental health care personnel establishing intravenous treatment and administering intravenous medications should be trained in safe injection practices.