Enfermedad del legionario en Argentina: evolución de la estrategia diagnóstica en el laboratorio / Legionnaires' disease in Argentina: Evolution of the laboratory diagnostic strategy

Resumen La enfermedad del legionario (EL) es una neumonía aguda grave, que ocurre espo-rádicamente o como epidemias, y que, generalmente, requiere hospitalización. El objetivo deeste trabajo fue describir la experiencia en el abordaje diagnóstico de laboratorio de la ELen Argentina durante el período 2016-2021. Se analizaron 168 especímenes clínicos correspondientes a 93 casos de neumonía con sospecha de EL. Las pruebas de laboratorio incluyeron ladeterminación del antígeno soluble de Legionella pneumophila serogrupo 1 en orina, la detec-ción de ADN de Legionella spp. en secreciones respiratorias bajas, por métodos moleculares convencionales y comerciales de tipo sindrómico, y el cultivo en medio selectivo. Se confirmó EL en 12 pacientes. El antígeno urinario confirmó el diagnóstico de 8 de ellos. Se recuperó L. pneumophila mediante el cultivo del material respiratorio de 6 pacientes que correspondieron a casos de neumonía asociada a cuidados de la salud y que fueron previamente diagnosticados por el método molecular comercial. La mitad de ellos no presentó antigenuria detectable. En un único paciente no hubo antigenuria detectable ni recuperación de Legionella en cultivo, y la confirmación de EL se basó en la detección de ADN de Legionella spp. por PCR en secreción respiratoria y el vínculo epidemiológico con otro caso de EL confirmado por cultivo. La detección del antígeno urinario es la prueba diagnóstica de primera línea. Sin embargo, la incorporación de métodos moleculares complementarios ha demostrado evitar falsos negativos y contribuir a un mejor conocimiento de la verdadera incidencia de la enfermedad.

Abstract Legionnaires' disease (LD) is severe acute pneumonia that occurs in sporadic or epidemic form, and generally requires hospitalizaron. The objective of this work was to describe the experience in the LD laboratory diagnostic approach in Argentina during the period 2016-2021. The laboratory analyzed 168 clinical specimens from 93 cases of suspected LD pneu-monia. Laboratory tests included the detection of the soluble antigen of Legionella pneumophila serogroup 1 in urine sample, detection of DNA of Legionella spp. in lower respiratory secre-tions by conventional and commercial molecular methods and isolation in selective medium. LD was confirmed in 12 patients. The urinary antigen allowed the diagnosis for 8 patients. L. pneumophila was isolated from the respiratory material of 6 patients suffering from health care-associated pneumonia, who had been previously diagnosed using the commercial molecular method. Fifty percent of these cases did not show detectable urinary antigen. A single patient did not shows neither detectable antigenuria nor isolation of Legionella from the respiratory sample and was diagnosed as a confirmed case of LD by the detection of DNA of Legionella spp. by PCR directly from the respiratory secretion and the epidemiological link with another case of confirmed LD by culture. Urinary antigen detection is the first-line diagnostic test. However, the incorporation of complementary molecular methods has proved to avoid false negatives and contributed to a better understanding of the true incidence of the disease.

Vigilancia epidemiológica de la legionelosis en España: 2005-2015 / Epidemiological surveillance of legionellosis in Spain: 2005-2015

Introducción: La legionelosis es una enfermedad de declaración obligatoria en España. Uno de sus mecanismos de prevención y control es el sistema de vigilancia epidemiológica y, en particular, la investigación epidemiológica. Entre 2005 y 2010 se reportó en Europa un aumento de la carga de la enfermedad no descrita en España. Objetivo: Determinar la evolución de los casos de legionelosis en España en la serie 2005-2015. Métodos: Estudio descriptivo de series temporales relativo al recuento de casos notificados a través del Centro Nacional de Epidemiología de España. Se incluyeron variables sociodemográficas del paciente, antecedentes personales y clínicos, síntomas y signos, datos de laboratorio y epidemiológicos. Se determinó la tasa de incidencia por 100 000 habitantes (2005-2010) y la tasa ajustada (población europea) por 100 000 habitantes según sexo (2005-2015), así como según grupo de edad y sexo para la serie 2010-2015. Resultados: España mantiene una tendencia estable respecto a la tasa de incidencia por 1100 000 habitantes (3,5 a 2,5), se produce un incremento relevante en la tasa ajustada a partir de los 50 años, con mayor impacto en los hombres. Conclusión: se evidencia la necesidad de la vigilancia epidemiológica de la legionelosis, la mejora en las medidas de prevención y control, y la consideración de nuevos factores de riesgo(AU)

Introduction: Legionellosis is a notifiable disease in Spain. One of its prevention and control mechanisms is epidemiological surveillance, particularly epidemiological research. An increase in legionellosis disease burden was reported in Europe from 2005 to 2010 which was not described in Spain. Objectives: Determine the evolution of legionellosis cases in Spain in the period 2005-2015. Methods: A descriptive time series analysis was performed based on the cases notified to the Spanish National Epidemiology Center. The variables considered were the patients' sociodemographic characteristics, personal and clinical antecedents, signs and symptoms, laboratory results and epidemiological data. Determination was made of the incidence rate per 100 000 inhabitants (2005-2010) and the adjusted rate per 100 000 inhabitants (European population) by sex (2005-2015) and by age group and sex for the series (2010-2015). Results: Incidence per 100 000 inhabitants has remained stable (3.5 to 2.5) in Spain, which has led to a relevant increase in the adjusted rate as of age 50 years, with a higher impact among men. Conclusion: Evidence was found of the need for epidemiological surveillance of legionellosis, improvement of prevention and control measures, and consideration of new risk factors(AU)

Mortalidad por neumonía y legionelosis en España: un estudio de series temporales / Pneumonia and legionellosis mortality in Spain: a time series study

Background: Pneumonia is a disease with great relevance in public health, as a leading individual cause of infant mortality worldwide. Legionellosis is a respiratory disease with a bacterial origin and two different clinical forms. Aim: To determine pneumonia and legionellosis mortality in Spain. Material and Methods: Time series study of pneumonia and legionellosis in Spain in two periods, from 1997 to 2001 and from 2011 to 2015. Mortality was calculated according to disease and sex, number of deaths and rates per 100,000 inhabitants. Results: Pneumonia mortality in the first period shows a relatively stable and similar tendency according to sex, preferably affecting males. In the second period, pneumonia mortality increased significantly in recent years. Although pneumonia mortality in Spain decreased in both sexes in some age groups (especially 75 years. Deaths due to legionellosis were relevant in 1997, 1998 and 2000 and increased in the last period. Conclusions: A higher mortality due to pneumonia along the years was identified. Strategies to reduce the incidence and improve the diagnosis of pneumonia, especially in children and older people elderly, are encouraged.

Legionelosis en España, 2010-2015 / Legionellosis in Spain, 2010-2015

Resumen | Introducción. La legionelosis es una enfermedad respiratoria bacteriana de origen ambiental que puede ser adquirida en el ámbito comunitario u hospitalario, y suele estar asociada con equipos, instalaciones y edificios. La forma clínica más conocida es la neumónica, conocida como enfermedad del legionario. Objetivo. Determinar la evolución de los casos de legionelosis en España en el periodo de 2010 a 2015. Materiales y métodos. Se hizo un estudio descriptivo de series temporales y se analizaron los casos de legionelosis notificados al Centro Nacional de Epidemiología del Gobierno de España. Se determinó la distribución de los casos según el sexo, la comunidad autónoma, el mes y los grupos de edad. Para el último se diferenció entre hombres y mujeres. Resultados. El recuento de casos en hombres fue superior al doble con respecto a las mujeres. La distribución en las comunidades autónomas presentó un aumento de los casos notificados al final del periodo en nueve de ellas, siendo notable en Castilla y León, Navarra y el País Vasco, y muy relevante en Castilla-La Mancha. Se estableció un patrón estacional con un pico epidémico en julio-septiembre y un mayor número de casos en torno a los 50 años de edad en ambos sexos. Conclusiones. A pesar de mostrar una prevalencia baja con respecto a otras enfermedades respiratorias, la legionelosis tiene gran impacto en la salud pública. Presenta una distribución global y heterogénea en el territorio español, con un aumento de casos en los dos últimos años, por lo que se requiere una mejor prevención y control de la enfermedad.

Abstract | Introduction: Legionellosis is a bacterial respiratory disease with an environmental origin in the community or in hospitals; it is usually associated with devices, facilities, and buildings. The most common clinical form is the pneumonic, known as legionnaires' disease. Objective: To determine the evolution of legionellosis cases in Spain from 2010 to 2015. Materials and methods: This was a descriptive study of time series with an analysis of the legionellosis cases notified to the Centro Nacional de Epidemiología (Government of Spain). Case distribution was determined according to sex, the autonomous community of origin, month, and age groups differentiating in the latter between men and women. Results: Case count in men was more than double compared to that in women. The cases notified by nine of the autonomous communities showed an increase at the end of the period, especially in Castilla y León, Navarra, and the Basque Country but also notable in Castilla-La Mancha. A seasonal pattern was identified with an epidemic peak in July-September and a greater number of cases among 50-years old people from both sexes. Conclusion: Despite its low prevalence compared to other respiratory diseases, legionellosis has a great impact on public health. Its distribution in Spain is global and heterogeneous with cases increasing in the last two years. Therefore, better disease prevention and control measures are recommended.

Biological risk of Legionella pneumophila in irrigation systems / Riesgo biológico por Legionella pneumophila en sistemas de riego

ABSTRACT Objective The goal of this study is to determine the risk of exposure to Legionella pneumophila in hotel golf courses located in the province of Malaga (Spain). Method Spray irrigation systems were analyzed as sources for spreading the Legionella bacterium. Spanish legislation requires that irrigation systems be monitored for their water quality as well as for reasons related to health and hygiene. Based on an observational study and non-parametric tests (Goodman-Kruskal Tau and uncertainty coefficient), this study states the regulatory enforcement among the systems and contributed to announce Legionella prevention. The quality criteria for recycled water, waste water treatment plant and well water were analyzed in relationship to the hotels' categories. Results Deficiencies were found in the preventive maintenance of irrigation systems, but no relationship exists between the type of water and the risk detected. Conclusions The study suggests that aerosolized water used in golf course watering systems could pose risk to the population by exposing them to Legionella.

RESUMEN Objetivo El propósito de este trabajo es determinar el riesgo de exposición a Legionella pneumophila en campos de golf de hoteles ubicados en la provincia de Málaga (España). Método Se realizó un estudio de los sistemas de riego por aspersión como fuentes de dispersión de la bacteria Legionella. El análisis de las condiciones higiénico-sanitarias de las instalaciones y la calidad del agua es una actividad de obligado cumplimiento contemplada en la legislación sanitaria española. Mediante un estudio observacional y el empleo de pruebas no paramétricas (Tau de Goodman-Kruskal y coeficiente de incertidumbre) se expresó el cumplimiento de la reglamentación en los sistemas estudiados y la prevención de Legionella. Los criterios de calidad para el agua reciclada, procedente de la estación depuradora de agua residual y de pozo, fueron analizados en relación con la categoría de los hoteles. Resultados Se encontraron deficiencias en el mantenimiento preventivo de los sistemas de riego, pero no hubo relación entre el tipo de agua y el riesgo identificado. Conclusiones El estudio sugiere que el agua aerosolizada proveniente de los sistemas de riego de los campos de golf presenta un riesgo de infección por Legionella para la población expuesta.

Legionelosis ocupacional en mayores de 18 años: revisión sistemática / Occupational legionella in adults over 18 years pf age: a systematic review

Resumen El objetivo es revisar la literatura científica sobre los problemas de salud derivados de la exposición laboral a Legionella spp. Revisión sistemática de la literatura científica recogida en las bases de datos MEDLINE (Pubmed), ISI-Web of Science (Institute for Scientific Information), Cochrane Library Plus, Literatura Latinoamericana de Información en Ciencias de la Salud (LILACS) y SCOPUS, hasta febrero 2015. Los descriptores utilizados fueron: "Legionnaires' Disease" "Legionellosis" "Occupational Exposure" "Occupational Diseases". Se obtuvieron 222 referencias, que tras aplicar los criterios de inclusión y exclusión, se seleccionaron 13 artículos a texto completo. De ellos 9 artículos describen la aparición de neumonía, 4 Fiebre de Pontiac, 1 legionelosis o presunta legionelosis y 3 muerte. El principal agente causal en los profesionales expuestos fue Legionella pneumophila serogrupo 1. La infección por legionela está ligada a las profesiones donde existe nebulización por agua, principalmente en los trabajadores sometidos a largas exposiciones o incluso a la re-exposición. Los brotes se producen de forma estacional, sobre todo en los meses más cálidos.

Abstract The scope of this paper is to review the available scientific literature about the effects on health of occupational exposure to Legionella spp. A systematic review of the scientific literature retrieved from the MEDLINE (via PubMed), ISI-Web of Science (Institute for Scientific Information), Cochrane Library, LILCAS and SCOPUS databases through February 2015 was conducted. The key words used were ««Legionnaires' Disease¼ «Legionellosis¼ «Occupational Exposure¼ «Occupational Diseases¼. Two hundred and twenty-two references were retrieved of which, after applying inclusion/exclusion criteria, 13 complete articles were selected. Of these, 9 describe pneumonia, 4 list Pontiac Fever, 1 reveals legionellosis and 3 result in death. The main causative agent of disease in workers exposed was Legionella pneumophila serogroup 1. Legionella spp infection is closely related to professions where there is nebulization with water, mainly among workers subjected to long exposure or even re-exposure. Outbreaks occurs seasonally, especially in the hottest months.

Legionelosis, ¿una nueva realidad en la República del Ecuador? / Legionellosis: a new reality in the Republic of Ecuador?

La legionelosis es una enfermedad respiratoria de origen ambiental y alcance mundial. En este artículo se describen las principales características, epidemiología y ámbito de distribución, así como la relevancia de su análisis en la República de Ecuador. Se sugiere el estudio de la enfermedad como una de las contribuciones posibles de neumonía y la identificación de agentes origen de la misma. Su desarrollo podría promover la disminución de la mortalidad por neumonía, considerada como una de las principales causas de muerte en el país.

Legionellosis is a respiratory disease with environmental origin and worldwide scope. This article describes the main features, epidemiology and distribution of the disease, and the relevance of the analysis in the Republic of Ecuador. It is suggested the study of the disease as one of the possible contributions of pneumonia and the identification of the disease causative agents. The development could promote reduction of mortality due to pneumonia, which is considered one of the leading causes of death in the country.

Legionelosis

La legionelosis es una enfermedad bacteriana de origen ambiental, con presentación en el ámbito comunitario y hospitalario. De distribución mundial, puede acontecer en forma de brotes y casos aislados o esporádicos. En el estudio se hace un recorrido histórico de la identificación del agente biológico causante (Legionella spp.) y de los principales eventos que condujeron a su descubrimiento. Asimismo, se describen los principales brotes acaecidos desde el inicio de la definición de la enfermedad, la incidencia de ésta última y su importancia relativa a la vigilancia y prevención...

Legionelosis is a bacterial disease of environmental origin present at community and hospital settings. It may appear worldwide in the form of isolated or sporadic outbreaks. A historical account of the identification of the causative biological agent (Legionella spp.) and the main events leading to the discovery was made. Likewise, the main outbreaks from the definition of the disease, its incidence to the importance of surveillance and prevention were all described...

Molecular Characterization of Legionellosis Drug Target Candidate Enzyme Phosphoglucosamine Mutase from Legionella pneumophila (strain Paris): An In Silico Approach

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.

Acciones de prevención y control de la legionelosis: un reto para la salud pública española / Actions for legionellosis prevention and control: a challenge for public health in Spain

La legionelosis es una enfermedad respiratoria con origen en sistemas que formen aerosol y que contenga el agente biológico Legionella sp. En las últimas décadas se ha desarrollado en España un marco normativo para su prevención y control. El presente artículo expone la epidemiología de la legionelosis y la importancia del control de la transmisión de la bacteria en la lucha contra la enfermedad. Para ello, se hace patente la revisión de las instalaciones críticas y la inclusión de otras nuevas en la legislación preventiva así como la estimación del riesgo, la mejora en los procesos de diagnóstico y el avance en nuevos protocolos de prevención.

Legionellosis is a respiratory disease originating in systems that produce aerosol and contain Legionella sp. In recent decades, Spain has developed a regulatory framework for prevention and control of legionellosis. This article describes the epidemiology of legionellosis and the importance of controlling the transmission of bacteria in the fight against the disease. In that regard, it becomes clear the role of reviewing critical facilities and the inclusion of new ones in the preventive legislation, the estimation of risk, and the improvement in the diagnostic processes and progress in new prevention protocols.

Isolation of Legionella pneumophila from clinical & environmental sources in a tertiary care hospital.

Background & objectives: Legionella pneumophila and other members of this genus are important respiratory pathogens but legionellosis often remains a neglected and under reported condition. Hence, this study was done to find out the presence of this organism in patients admitted to a tertiary care hospital with community-acquired pneumonia (CAP). Methods: A total of 470 lower respiratory tract samples and 24 water samples from hospital outlets were examined. Culture was done on buffered charcoal yeast extract agar with supplements and identification of the isolates was done by microscopy and biochemical tests. Results: L. pneumophila could be isolated from 12 (2.55%) patients suffering from community-acquired lower respiratory tract infection, unassociated with other aetiological agents of bacterial pneumonia. Of the 24 water samples tested, 8 (33.3%) grew the same organism. Interpretation & conclusion: Our study has shown that Legionella is present in the hospital environment and was the aetiological agent of lower respiratory tract infection in 2.55 per cent of patients. A larger study and reports from other parts of the country may help in determining the true significance of legionellosis in India.