Multiple Sources of the Outbreak of Legionnaires’ Disease in Genesee County, Michigan, in 2014 and 2015

The 2014–2015 Legionnaires’ disease (LD) outbreak in Genesee County, MI, and the outbreak resolution in 2016 coincided with changes in the source of drinking water to Flint’s municipal water system. Following the switch in water supply from Detroit to Flint River water, the odds of a Flint resident presenting with LD increased 6.3-fold (95% CI: 2.5, 14.0). This risk subsided following boil water advisories, likely due to residents avoiding water, and returned to historically normal levels with the switch back in water supply. During the crisis, as the concentration of free chlorine in water delivered to Flint residents decreased, their risk of acquiring LD increased. When the average weekly chlorine level in a census tract was <0.5 mg/L or <0.2 mg/L, the odds of an LD case presenting from a Flint neighborhood increased by a factor of 2.9 (95% CI: 1.4, 6.3) or 3.9 (95% CI: 1.8, 8.7), respectively. During the switch, the risk of a Flint neighborhood having a case of LD increased by 80% per 1 mg/L decrease in free chlorine, as calculated from the extensive variation in chlorine observed. In communities adjacent to Flint, the probability of LD occurring increased with the flow of commuters into Flint. Together, the results support the hypothesis that a system-wide proliferation of legionellae was responsible for the LD outbreak in Genesee County, MI.

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Excess Pneumonia Mortality During a Legionnaires’ Disease Outbreak in Flint, Michigan

10.1101/19005942 ◽

2019 ◽

Cited By ~ 1

Author(s):

ZO Binney ◽

KN Nelson ◽

AT Chamberlain

Keyword(s):

Human Services ◽

Community Acquired Pneumonia ◽

County Level ◽

Uncertainty Interval ◽

Health And Human Services ◽

Department Of Health ◽

Case Count ◽

Vital Records ◽

Legionnaires Disease ◽

Genesee County

AbstractIntroductionFrom June 2014-October 2015, the Michigan Department of Health and Human Services (MDHHS) reported a Legionnaires’ disease (LD) outbreak in Genesee County, Michigan, of which Flint is the county seat. MDHHS’ final case count for the outbreak was 90 cases, including 10 deaths among Genesee County residents. As LD is not routinely tested for as a cause of community-acquired pneumonia, the size of the outbreak may have been underestimated. Specifically, some LD cases may have been classified as pneumonias of other or unexplained etiologies.ObjectiveTo estimate excess pneumonia deaths in Genesee County during the 2014-15 LD outbreak and compare this with reported deaths due to LD.MethodsWe used data from the CDC WONDER database, which contains monthly county-level counts of death certificates, on all pneumonia deaths among residents of Genesee and a set of similar counties from 2011-2017. We calculated excess pneumonia deaths in Genesee during the period of the LD outbreak (May 2014-October 2015). We used data from the Genesee County Vital Records Division to map pneumonia deaths by census tract to assess geographic overlap with reported LD cases.ResultsWe estimated 70.0 excess pneumonia deaths (90% uncertainty interval (UI): 36 to 103) in Genesee County during the LD outbreak. This is substantially higher than the 10 LD deaths among Genesee County residents reported by MDHHS. Areas of high pneumonia mortality overlapped with those with high LD incidence and were primarily located in western Flint and northwestern non-Flint Genesee County.ConclusionsThese findings are consistent with the hypothesis that the LD outbreak was larger than reported. Earlier detection and response to this outbreak may have facilitated identification of these additional cases.

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Epidemiological investigation and case–control study: a Legionnaires’ disease outbreak associated with cooling towers in Warstein, Germany, August–September 2013

Eurosurveillance ◽

10.2807/1560-7917.es.2015.20.46.30064 ◽

2015 ◽

Vol 20 (46) ◽

Cited By ~ 15

Author(s):

Anna Maisa ◽

Ansgar Brockmann ◽

Frank Renken ◽

Christian Lück ◽

Stefan Pleischl ◽

...

Keyword(s):

Legionella Pneumophila ◽

Case Control Study ◽

Case Fatality ◽

Case Control ◽

Cooling Towers ◽

Multiple Sources ◽

Source Tracing ◽

Infection Source ◽

Legionnaires Disease ◽

Control Study

Between 1 August and 6 September 2013, an outbreak of Legionnaires’ disease (LD) with 159 suspected cases occurred in Warstein, North Rhine-Westphalia, Germany. The outbreak consisted of 78 laboratory-confirmed cases of LD, including one fatality, with a case fatality rate of 1%. Legionella pneumophila, serogroup 1, subtype Knoxville, sequence type 345, was identified as the epidemic strain. A case–control study was conducted to identify possible sources of infection. In univariable analysis, cases were almost five times more likely to smoke than controls (odds ratio (OR): 4.81; 95% confidence interval (CI): 2.33–9.93; p < 0.0001). Furthermore, cases were twice as likely to live within a 3 km distance from one identified infection source as controls (OR: 2.14; 95% CI: 1.09–4.20; p < 0.027). This is the largest outbreak of LD in Germany to date. Due to a series of uncommon events, this outbreak was most likely caused by multiple sources involving industrial cooling towers. Quick epidemiological assessment, source tracing and shutting down of potential sources as well as rapid laboratory testing and early treatment are necessary to reduce morbidity and mortality. Maintenance of cooling towers must be carried out according to specification to prevent similar LD outbreaks in the future.

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Excess Pneumonia Mortality During a 2014–2015 Legionnaires’ Disease Outbreak in Genesee County, Michigan

Epidemiology ◽

10.1097/ede.0000000000001240 ◽

2020 ◽

Vol 31 (6) ◽

pp. 823-831

Author(s):

Kristin N. Nelson ◽

Zachary O. Binney ◽

Allison T. Chamberlain

Keyword(s):

Disease Outbreak ◽

Legionnaires Disease ◽

Genesee County

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An outbreak of Legionnaires' disease in Gloucester

Epidemiology and Infection ◽

10.1017/s0950268800048767 ◽

1991 ◽

Vol 107 (1) ◽

pp. 133-141 ◽

Cited By ~ 15

Author(s):

D. A. Hunt ◽

K. A. V. Cartwright ◽

M. C. Smith ◽

J. Middleton ◽

C. L. R. Bartlett ◽

...

Keyword(s):

Legionella Pneumophila ◽

Case Control Study ◽

Case Finding ◽

Unexpected Finding ◽

Cooling Towers ◽

Multiple Sources ◽

Pontiac Fever ◽

Legionnaires Disease ◽

The City ◽

Control Study

SUMMARYFourteen people living in or near the city of Gloucester fell ill with Legionnaires' disease caused by Legionella pneumophila serogroup (SG) 1 between 27 August and 27 October 1986. Another patient had fallen ill on 30 May. Nine of the 15 were diagnosed retrospectively during a case finding exercise. There were three deaths. Three cases of Pontiac fever were also diagnosed.The source was probably one or more wet cooling towers. Nineteen premises in the city with such towers were identified, and three just outside Gloucester. Samples from 11 of the 22 premises grew Legionella spp.; from nine of these L. pneumophila SG 1 (Pontiac) was isolated. The efficacy of regular addition of biocide in addition to hypochlorite added at the time of disinfection in inhibiting the growth of Legionella spp. was demonstrated.A survey of patients' movements during their likely incubation period showed that there was no single building that all patients had visited, but there were two areas of the city which nearly all had visited or passed through by car. A case-control study demonstrated an association with one of these areas.Cooling towers near both areas may have been sources but the evidence is insufficient to incriminate any single one. The unexpected finding of L. pneumophila SG 1 (Pontiac) in nine towers supports the hypothesis that there may have been multiple sources. Cooling towers may have been contaminated by mains water or by drift from other towers.

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675. Current Physician Knowledge, Attitudes, and Clinical Practice Regarding Legionnaires’ Disease in the Aftermath of the Flint Water Crisis in Genesee County, Michigan

Open Forum Infectious Diseases ◽

10.1093/ofid/ofy210.682 ◽

2018 ◽

Vol 5 (suppl_1) ◽

pp. S244-S244

Author(s):

Katanya C Alaga ◽

Jewel M Konja ◽

Abdulbaset Salim ◽

Pete Levine ◽

Sherry Smith ◽

...

Keyword(s):

Clinical Practice ◽

Clinical Guidelines ◽

Tap Water ◽

The United States ◽

Medical Society ◽

Healthcare Personnel ◽

Monthly Bulletin ◽

Attitudes And Practices ◽

Legionnaires Disease ◽

Genesee County

Abstract Background Legionnaires’ disease (LD) is a respiratory illness caused by the inhalation of aerosolized water contaminated with Legionella bacteria. For reasons not yet understood, the incidence of LD has steadily increased across the United States during the past 10 years. In 2014 and 2015, the City of Flint in Genesee County (GC), Michigan underwent a change in the city’s water source, which resulted in the third largest recorded LD outbreak in American history and over 100,000 residents being exposed to contaminated water. In order to reduce the incidence of LD in at-risk populations it is imperative that we evaluate and improve LD knowledge and clinical practice among healthcare personnel. Methods This investigation surveyed clinicians practicing in Genesee County who are also members of the Genesee County Medical Society (GCMS). A survey was designed to assess current clinical knowledge, attitudes, and practices related to LD, in addition to measuring the uptake and utility of the LD clinical guidelines. The survey and the LD clinical guidelines were distributed to all GCMS members over a 6-month period. Prompts to complete the survey using Qualtrics programming were emailed to GCMS members and posted in the GCMS monthly bulletin. In addition, surveys were distributed to members at GCMS meetings. Completed responses were entered into Qualtrics software and exported into MS Excel and SPSS statistical software for analysis. Results In total, 95 healthcare personnel responded. Of those surveyed, 79.5% have been in practice for more than 10 years and 55% identified as practicing in family, internal or emergency medicine. Despite, the well-publicized LD outbreak in GC, 45% of respondents did not believe or were unsure if LD was a current public health issue, and 65% have either not received, have received but are not interested, or have received but not read the LD clinical guidelines. Despite this, 47% and 61% of respondents were able to correctly identify the symptoms and risk factors for LD, respectively. In addition, 34% of participants believe that drinking tap water is a risk factor for contracting LD. Conclusion This survey underscores the continuing need for comprehensive physician education to improve the clinical recognition and evaluation of patients with LD. Disclosures All authors: No reported disclosures.

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Agreeableness, Conflict Resolution Tactics, and School Behavior in Second Graders

Journal of Individual Differences ◽

10.1027/1614-0001/a000199 ◽

2016 ◽

Vol 37 (3) ◽

pp. 145-151 ◽

Cited By ~ 2

Author(s):

Daniel L. Gadke ◽

Renée M. Tobin ◽

W. Joel Schneider

Keyword(s):

Conflict Resolution ◽

Problem Behaviors ◽

Second Graders ◽

Adaptive Behaviors ◽

Second Grade ◽

School Behavior ◽

Multiple Sources ◽

School Based ◽

Second Grade Students ◽

Negotiation Tactics

Abstract. This study examined the association between Agreeableness and children’s selection of conflict resolution tactics and their overt behaviors at school. A total of 157 second graders responded to a series of conflict resolution vignettes and were observed three times during physical education classes at school. We hypothesized that Agreeableness would be inversely related to the endorsement of power assertion tactics and to displays of problem behaviors, and positively related to the endorsement of negotiation tactics and to displays of adaptive behaviors. Consistent with hypotheses, Agreeableness was inversely related to power assertion tactics and to displays of off-task, disruptive, and verbally aggressive behaviors. There was no evidence that Agreeableness was related to more socially sophisticated responses to conflict, such as negotiation, with our sample of second grade students; however, it was related to displays of adaptive behaviors, specifically on-task behaviors. Limitations, including potential reactivity effects and the restriction of observational data collection to one school-based setting, are discussed. Future researchers are encouraged to collect data from multiple sources in more than one setting over time.

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