ABSTRACT
In autumn 2022, the Spanish Influenza National Reference Laboratory (NRL) confirmed the detection of influenza A(H5N1) in samples from two asymptomatic workers linked to an outbreak in a poultry farm in Spain. Nasopharyngeal swabs were taken according to a national screening protocol for exposed workers. Absence of symptoms, low viral load and negative serology in both workers suggested environmental contamination. These findings motivated an update of the early detection strategy specifying timing and sampling conditions in asymptomatic exposed persons.
Subject(s)
Influenza A Virus, H5N1 Subtype , Influenza in Birds , Influenza, Human , Poultry Diseases , Animals , Humans , Influenza, Human/diagnosis , Influenza, Human/epidemiology , Influenza in Birds/diagnosis , Influenza in Birds/epidemiology , Poultry , Spain/epidemiology , Farmers , Disease Outbreaks/veterinary , Poultry Diseases/epidemiologyABSTRACT
INTRODUCTION: In Spain, like in other countries where endemic measles has been eliminated, there is a need for available diagnostic tolos for confirming any cases in order to prevent and control its transmission. We describe the different microbiological tests used for the diagnosis of measles during an outbreak that occurred in 2019 in the province of Guadalajara (Spain). METHODS: Serological and molecular tests were performed at the Microbiology laboratory of the Guadalajara University Hospital and at the National Center for Microbiology of the Carlos III Health Institute (Majadahonda, Spain). Patient data were obtained from the surveillance system. RESULTS: A total of 43 patients had a laboratory diagnosis of measles: 29 cases by PCR (pharyngeal exudate or urine) and positive specific IgM, 11 cases by PCR, and 3 cases only by a positive IgM. Genotype D8 was identified in 35 confirmed cases and genotype A in two that were discarded as post-vaccination cases. PCR was positive in the acute sera of 11 out of 14 patients with a negative IgM. Eleven confirmed cases had recieved one or two vaccine doses. Twelve adult patients were hospitalizated, all of them with a diagnostic of hepatitis. CONCLUSIONS: The combination of molecular tests and the presence of specific IgM is necessary for a correct diagnosis of measles and also to classify patients with a breakthrough infection or vaccine failures (primary or secondary). Genotyping is essential for the correct classification of the patients in the context of a measles elimination program.
Subject(s)
Measles virus , Measles , Adult , Humans , Measles virus/genetics , Spain/epidemiology , Antibodies, Viral , Measles/diagnosis , Measles/epidemiology , Measles/prevention & control , Disease Outbreaks , Immunoglobulin MABSTRACT
INTRODUCTION: In Spain, like in other countries where endemic measles has been eliminated, there is a need for available diagnostic tools for confirming any cases in order to prevent and control its transmission. We describe the different microbiological tests used for the diagnosis of measles during an outbreak that occurred in 2019 in the province of Guadalajara (Spain). METHODS: Serological and molecular tests were performed at the Microbiology laboratory of the Guadalajara University Hospital and at the National Center for Microbiology of the Carlos III Health Institute (Majadahonda, Spain). Patient data were obtained from the surveillance system. RESULTS: A total of 43 patients had a laboratory diagnosis of measles: 29 cases by PCR (pharyngeal exudate or urine) and positive specific IgM, 11 cases by PCR, and 3 cases only by a positive IgM. Genotype D8 was identified in 35 confirmed cases and genotype A in 2 that were discarded as post-vaccination cases. PCR was positive in the acute sera of 11 out of 14 patients with a negative IgM. Eleven confirmed cases had recieved one or 2 vaccine doses. Twelve adult patients were hospitalizated, all of them with a diagnostic of hepatitis. CONCLUSIONS: The combination of molecular tests and the presence of specific IgG and IgM are necessary for a correct diagnosis of measles and also to classify patients with a breakthrough infection or vaccine failures (primary or secondary). Genotyping is essential for the correct classification of the patients in the context of a measles elimination program.
ABSTRACT
Introducción: En España, al igual que en otros países donde el sarampión endémico ha sido eliminado, es necesario utilizar de forma rutinaria las herramientas diagnósticas que confirmen los casos para su prevención y control de la diseminación. Se describen los diferentes ensayos microbiológicos utilizados para su diagnóstico durante un brote de sarampión en 2019 en la provincia de Guadalajara (España). Métodos: Las pruebas serológicas y moleculares se realizaron en el laboratorio de Microbiología del Hospital Universitario de Guadalajara y en el Centro Nacional de Microbiología del Instituto de Salud Carlos III (Majadahonda, España). Los datos de los pacientes se obtuvieron del sistema epidemiológico de vigilancia. Resultados: Se diagnosticaron de sarampión un total de 43 pacientes por métodos microbiológicos: 29 casos por PCR (exudado faríngeo u orina) junto con IgM específica positiva, 11 pacientes solamente por PCR, y 3 pacientes exclusivamente por presencia de IgM. El genotipo D8 fue identificado en 35 pacientes y el genotipo A en 2 casos descartados como postvacunal. La PCR en suero fue positiva en 11 de 14 pacientes con ausencia de IgM en su primera muestra recogida de suero. Once casos confirmados habían recibido una o 2 dosis de la vacuna. Doce adultos fueron ingresados, todos diagnosticados de hepatitis. Conclusiones: La combinación de pruebas moleculares y la presencia de IgG e IgM específicas son necesarias para un diagnóstico correcto y la clasificación de los pacientes como fallo vacunal (primario o secundario). El genotipado es una herramienta fundamental para la correcta clasificación de los pacientes en el contexto de un programa de eliminación del sarampión.(AU)
Introduction: In Spain, like in other countries where endemic measles has been eliminated, there is a need for available diagnostic tools for confirming any cases in order to prevent and control its transmission. We describe the different microbiological tests used for the diagnosis of measles during an outbreak that occurred in 2019 in the province of Guadalajara (Spain). Methods: Serological and molecular tests were performed at the Microbiology laboratory of the Guadalajara University Hospital and at the National Center for Microbiology of the Carlos III Health Institute (Majadahonda, Spain). Patient data were obtained from the surveillance system. Results: A total of 43 patients had a laboratory diagnosis of measles: 29 cases by PCR (pharyngeal exudate or urine) and positive specific IgM, 11 cases by PCR, and 3 cases only by a positive IgM. Genotype D8 was identified in 35 confirmed cases and genotype A in 2 that were discarded as post-vaccination cases. PCR was positive in the acute sera of 11 out of 14 patients with a negative IgM. Eleven confirmed cases had recieved one or 2 vaccine doses. Twelve adult patients were hospitalizated, all of them with a diagnostic of hepatitis. Conclusions: The combination of molecular tests and the presence of specific IgG and IgM are necessary for a correct diagnosis of measles and also to classify patients with a breakthrough infection or vaccine failures (primary or secondary). Genotyping is essential for the correct classification of the patients in the context of a measles elimination program.(AU)