Aim: The aim of this study was to monitor the restricted water systems during the period of COVID-19 lockdown for the waterborne pathogen Legionella pneumophila. Selected water systems were monitored to evaluate the effect of stagnation in terms of Legionella colonization. Methodology and results: A total of 160 water samples were taken from buildings which were temporarily shut down or had restricted usage between April-December 2020. None of the sampling points had Legionella positive history in the last three years. All water samples were tested using classic microbiological culture as the gold standard and rapid Vermicon ScanVIT Legionella test kit combined with epifluorescence microscopy. Sixteen (10%) out of 160 water samples were recorded as Legionella-positive by both methods, where none of them was positive before the COVID-19 lockdown. All positives were tested as L. pneumophila serogroup 1 with latex agglutination kit. Conclusion, significance and impact of study Colonization of Legionella in stagnant water systems occurs rapidly. Before reopening, routine monitoring in buildings is extremely important especially under restricted use or closure is in case. Flushing, disinfecting and testing are crucial for minimizing the health risks for the public health.
Legionella ; Sanitary Engineering ; COVID-19 ; Waterborne Diseases ; Legionnaires' ; Disease

As a type of
Humans ; Legionella/genetics* ; Legionella longbeachae/genetics* ; Legionellosis/drug therapy* ; Pneumonia/diagnosis* ; Retrospective Studies

Legionella species are abundant in the built environment and are increasingly recognized as a cause of Legionnaires' disease (LD). As the number of cases of Legionnaires' disease acquired by local communities in the Seoul metropolitan area in Korea has been increased, there was concern that changes in environmental factors could affect disease outbreaks. We described the association between climatic variables and occurrence of legionellosis in Korea and Legionella detection rate in Seoul area. A total of 418 cases of legionellosis were reported between 2014 and 2017. There was a seasonal peak in summer. LD continuously occurred from early spring to winter every year and rapidly increased in summer. In the regression analysis, the primary variables of interest- PM2.5 (µg/m³), NO₂ (ppb), and a number of the date of issue O₃ warning were not significant except for average temperature (R²=0.8075). The Legionella detection rate in Seoul, Korea showed a trend similar to precipitation (P=0.708, ANOVA). A relatively high proportion of Legionella detection rate was shown, especially cooling tower (17.7%) and public bath (19.3%). This finding is in line with current understanding of the ecological profile of this pathogen and supports the assertion that legionellosis occurs through contamination of water sources.
Baths ; Disease Outbreaks ; Epidemiology ; Korea ; Legionella ; Legionellosis ; Legionnaires' Disease ; Regression Analysis ; Seasons ; Seoul ; Water

OBJECTIVES: Legionnaires' disease (LD) is a severe type of pneumonia caused by inhalation of aerosols contaminated with Legionella. On September 22, 2016, a single case of LD was reported from a newly built apartment building in Gyeonggi province. This article describes an epidemiologic investigation of LD and identification of the possible source of infection. METHODS: To identify the source of LD, we interviewed the patient's husband using a questionnaire based on the Legionella management guidelines from the Korea Centers for Disease Control and Prevention. Water samples from the site were collected and analyzed. An epidemiological investigation of the residents and visitors in the apartment building was conducted for 14 days before the index patient's symptoms first appeared to 14 days after the implementation of environmental control measures. RESULTS: Legionella pneumophila serogroup 1 was isolated from the heated-water samples from the patient's residence and the basement of the apartment complex. Thirty-two suspected cases were reported from the apartment building during the surveillance period, yet all were confirmed negative based on urinary antigen tests. CONCLUSIONS: The likely source of infection was the building's potable water, particularly heated water. Further study of effective monitoring systems in heated potable water should be considered.
Aerosols ; Centers for Disease Control and Prevention (U.S.) ; Disease Outbreaks ; Drinking Water ; Gyeonggi-do ; Hot Temperature ; Humans ; Inhalation ; Korea ; Legionella ; Legionella pneumophila ; Legionnaires' Disease ; Pneumonia ; Serogroup ; Spouses ; Water

Legionella pneumonia (LP) is a rare systemic infectious disease, which is often misdiagnosed by clinicians due to the atypical symptoms. A middle-aged man who suffered from fever and dyspnea was diagnosed as community acquired pneumonia (CAP) in Changsha Central Hospital in March 2015. The treatment was unsatisfied firstly. The patients showed further symptoms of rhabdomyolysis, acute liver and renal failure, and impaired neural functions, who was diagnosed as LP with multiple organ failure based on a positive test for Legionella antibody. The patient was recovered after treated with moxifloxacin combined with azithromycin and continuous renal replacement therapy. LP should be paid attention when patient was diagnosed as CAP and failed to be treated. The satisfied outcome is achieved after application of macrolide, quinolones and comprehensive treatments.
Anti-Bacterial Agents ; Community-Acquired Infections ; Fluoroquinolones ; Humans ; Legionella ; Legionnaires' Disease ; Male ; Middle Aged ; Moxifloxacin ; Multiple Organ Failure ; Pneumonia, Bacterial

The harshness of legionellosis differs from mild Pontiac fever to potentially fatal Legionnaire's disease. The increasing development of drug resistance against legionellosis has led to explore new novel drug targets. It has been found that phosphoglucosamine mutase, phosphomannomutase, and phosphoglyceromutase enzymes can be used as the most probable therapeutic drug targets through extensive data mining. Phosphoglucosamine mutase is involved in amino sugar and nucleotide sugar metabolism. The purpose of this study was to predict the potential target of that specific drug. For this, the 3D structure of phosphoglucosamine mutase of Legionella pneumophila (strain Paris) was determined by means of homology modeling through Phyre2 and refined by ModRefiner. Then, the designed model was evaluated with a structure validation program, for instance, PROCHECK, ERRAT, Verify3D, and QMEAN, for further structural analysis. Secondary structural features were determined through self-optimized prediction method with alignment (SOPMA) and interacting networks by STRING. Consequently, we performed molecular docking studies. The analytical result of PROCHECK showed that 95.0% of the residues are in the most favored region, 4.50% are in the additional allowed region and 0.50% are in the generously allowed region of the Ramachandran plot. Verify3D graph value indicates a score of 0.71 and 89.791, 1.11 for ERRAT and QMEAN respectively. Arg419, Thr414, Ser412, and Thr9 were found to dock the substrate for the most favorable binding of S-mercaptocysteine. However, these findings from this current study will pave the way for further extensive investigation of this enzyme in wet lab experiments and in that way assist drug design against legionellosis.
Computer Simulation* ; Data Mining ; Drug Delivery Systems ; Drug Design ; Drug Resistance ; Fever ; Legionella pneumophila* ; Legionellosis* ; Legionnaires' Disease ; Metabolism ; Phosphoglycerate Mutase

BACKGROUNDLegionella is an important community-acquired pneumonia pathogen. Although the elderly are especially susceptible to Legionella, few studies have looked at comparative radiographic features of Legionella pneumonia in this population. The aim of this study was to explore the chest radiographic characteristics of community-acquired Legionella pneumonia in the elderly.

METHODSSerial chest radiographs obtained in 34 patients hospitalized with serologically proven Legionella pneumonia were retrospectively reviewed. Chest X-ray features of an aged group of ≥ 65 years were assessed and compared with a non-aged group of <65 years old with regard to initial patterns and distributions of pulmonary abnormalities, accompanying signs, and progression.

RESULTSThe most common initial presentation was a patchy alveolar infiltrate involving a single lobe, most often the lower lobe. There was no middle or lingular lobe involvement in the aged group patients, but bilateral pleural effusion was significantly more common in this group. In the aged group patients, radiographic progression following adequate therapy, despite a clinical response, was more often noted and the radiographs were less likely to have returned to the premorbid state at discharge, but the differences were not significant between the two groups.

CONCLUSIONThe discrepancy between imaging findings and clinical symptoms seems more prominent in community-acquired Legionella pneumonia in the elderly.

Adolescent ; Adult ; Community-Acquired Infections ; diagnostic imaging ; Female ; Humans ; Legionella ; pathogenicity ; Legionnaires' Disease ; diagnostic imaging ; Lung ; diagnostic imaging ; microbiology ; Male ; Middle Aged ; Pneumonia ; diagnostic imaging ; Radiography ; Retrospective Studies ; Young Adult

Endogenous lipoid pneumonia is an uncommon condition. This is a report of a 29-year-old woman diagnosed with endogenous lipoid pneumonia associated with Legionella pneumophila serogroup 1 infection. The patient's endogenous lipoid pneumonia resolved completely after treatment for Legionella pneumophila infection. This suggests that early diagnosis and aggressive treatment of the underlying infection may prevent any long-term sequelae of lipoid pneumonia.
Adult ; Anti-Bacterial Agents ; therapeutic use ; Aza Compounds ; therapeutic use ; Azithromycin ; therapeutic use ; Female ; Fluoroquinolones ; Humans ; Legionella pneumophila ; classification ; Legionnaires' Disease ; diagnosis ; drug therapy ; microbiology ; Pneumonia, Lipid ; diagnosis ; drug therapy ; microbiology ; Quinolines ; therapeutic use ; Treatment Outcome

BACKGROUND: Differentiation of atypical pathogens is important for community-acquired pneumonia (CAP). In this study, we compared sputum and nasopharyngeal swabs (NPS) for use in detection of Mycoplasma pneumoniae (MP), Chlamydophila pneumoniae (CP), and Legionella pneumophila (LP), using Seeplex PneumoBacter ACE Detection Assay (PneumoBacter; Seegene). METHODS: Sputum and NPS specimens were collected from patients in 15 hospitals. DNA was extracted from sputum using QIAamp DNA Stool Mini Kit (Qiagen) and from NPS using easyMAG (bioMerieux). Both types of specimens were evaluated by multiplex PCR using PneumoBacter. To determine the diagnostic performance of this assay, sputum samples were also tested using BD ProbeTec ET Atypical Pneumonia Assay (APA; Becton Dickinson). RESULTS: Among 217 sputum and NPS, 20 (9.2%), 2 (0.9%), and 0 sputum were positive for MP, LP, and CP, respectively, whereas 8 (3.7%) NPS were positive for MP. The sputum APA test yielded 186, 206, and 204 interpretable results for MP, LP, and CP, respectively. Of these, 21 (11.3%) were positive for MP, 2 (1.0%) were positive for LP, and 0 samples were positive for CP. Compared to APA, the sensitivity and specificity of the sputum assay for MP were 95.2% and 100.0%, respectively, whereas for the NPS assay, these were 38.1% and 93.9%. Sputum testing was more sensitive than NPS testing (P=0.002). For LP and CP diagnosis, PneumoBacter and APA tests agreed 100%. CONCLUSIONS: Specimen type is crucial and sputum is preferred over NPS for simultaneous detection of MP, LP, and CP using multiplex PCR in CAP.
Chlamydophila Infections/diagnosis ; Chlamydophila pneumoniae/*genetics/isolation & purification ; Community-Acquired Infections/*diagnosis ; DNA, Bacterial/analysis/isolation & purification ; Humans ; Legionella pneumophila/*genetics/isolation & purification ; Legionnaires' Disease/diagnosis ; Multiplex Polymerase Chain Reaction ; Mycoplasma pneumoniae/*genetics/isolation & purification ; Nasopharynx/*microbiology ; Pneumonia, Mycoplasma/diagnosis ; Reagent Kits, Diagnostic ; Sputum/*microbiology

BACKGROUNDThe environmental sources associated with community-acquired or nosocomial legionellosis were not always detectable in the mainland of China and Hong Kong, China. The objective of this study was to illustrate the control measures implemented for nosocomial and community outbreaks of legionellosis, and to understand the environmental distribution of legionella in the water system in Hong Kong, China.

METHODSWe investigated the environmental sources of two cases of legionellosis acquired in the hospital and the community by extensive outbreak investigation and sampling of the potable water system using culture and genetic testing at the respective premises.

RESULTSThe diagnosis of nosocomial legionellosis was suspected in a patient presenting with nosocomial pneumonia not responsive to multiple beta-lactam antibiotics with subsequent confirmation by Legionella pneumophila serogroup 1 antigenuria. High counts of Legionella pneumophila were detected in the potable water supply of the 70-year-old hospital building. Another patient on continuous ambulatory peritoneal dialysis presenting with acute community-acquired pneumonia and severe diarrhoea was positive for Legionella pneumophila serogroup 1 by polymerase chain reaction (PCR) testing on both sputum and nasopharyngeal aspirate despite negative antigenuria. Paradoxically the source of the second case was traced to the water system of a newly commissioned office building complex. No further cases were detected after shock hyperchlorination with or without superheating of the water systems. Subsequent legionella counts were drastically reduced. Point-of-care infection control by off-boiled or sterile water for mouth care and installation of water filter for showers in the hospital wards for immunocompromised patients was instituted. Territory wide investigation of the community potable water supply showed that 22.1% of the household water supply was positive at a mean legionella count of 108.56 CFU/ml (range 0.10 to 639.30 CFU/ml).

CONCLUSIONSPotable water systems are open systems which are inevitably colonized by bacterial biofilms containing Legionella species. High bacterial counts related to human cases may occur with stagnation of flow in both old or newly commissioned buildings. Vigilance against legionellosis is important in healthcare settings with dense population of highly susceptible hosts.

Aged ; Aged, 80 and over ; Biofilms ; Community-Acquired Infections ; diagnosis ; epidemiology ; Female ; Hong Kong ; epidemiology ; Humans ; Legionellosis ; diagnosis ; epidemiology ; Male ; Water Microbiology