Inmaculada Casas Flecha

Role of Rhinovirus in Hospitalized Infants With Respiratory Tract Infections in Spain

Background: Rhinovirus is a recognized cause of common cold, proven to cause asthma exacerbations in children. In Spain, no description exists, as yet, as to the degree of burden rhinovirus infections represent among hospitalized infants. Our aim was to describe rhinovirus infections in hospitalized children, under 2 years of age, and to compare these with patients infected with respiratory syncytial virus (RSV). Patients and Methods: The prospective study was performed between September 2003 and July 2005, in children <2 years of age, admitted at the Severo Ochoa Hospital (Leganés, Madrid) with fever or respiratory tract infection and with positive rhinovirus detection in the nasopharyngeal aspirate samples. Virologic diagnosis was made by multiplex reverse transcription-polymerase chain reaction and for some virus by direct immunofluorescent assay in nasopharyngeal samples. Demographic and clinical data of those patients with rhinovirus infection were described and compared with a group of 86 patients, infected only with RSV, randomly selected from the same population. Results: We detected 85 children admitted to hospital with rhinovirus infection. Rhinovirus was the cause of 25% of all admissions, among the total of 340 under 2-year olds diagnosed with fever or respiratory tract infection. Rhinovirus was the second viral agent identified, after RSV. Clinical diagnosis was recurrent wheezing in 48.2%; bronchiolitis in 36.5%; and pneumonia in 3.5%. Fever was present in 60% of the patients. Radiologic infiltrates were found in 22.4% of the children. In 50.6% of the infants, oxygen saturation under 95% was detected, at the time of admission. Hypoxia was present in RSV-infected children more frequently (P = 0.005). Also, in this group, final diagnosis was, most frequently, bronchiolitis (P = 0.0001), and rhinovirus-infected patients were most frequently males (P = 0.004). Conclusions: Rhinovirus was detected in hospitalized infants with respiratory tract disease and was the second most common virus after RSV. In our experience, it was the second etiologic agent associated with recurrent wheezing in hospitalized children, under the age of 2 years.

Epidemiology of the 2009 influenza pandemic in Spain. The Spanish Influenza Surveillance System

In accordance with European Centre for Disease Prevention and Control recommendations, the Spanish Influenza Surveillance System (SISS) maintained its activity during the summer of 2009, and since July 2009 the pandemic virus activity was monitored by the SISS. In this paper, we describe the epidemiological and virological characteristics of the 2009 pandemic in the Spain through the SISS. Spain experienced a transmission of the new A(H1N1)pdm09 influenza virus during the summer of 2009, which gradually increased, resulting in the pandemic wave in early autumn of that year. The reproductive number R0, estimated during the growth phase of the pandemic wave (1.32; 95% confidence interval [95%CI], 1.29-1.36), showed a transmissibility comparable to preceding pandemics. There was an almost complete replacement of the previous seasonal A(H1N1) influenza virus by the pandemic virus A(H1N1)pdm09. The pandemic virus produced a greater burden of illness than seasonal influenza in children younger than 15 years old, while the incidence in those older than 64 years was lower compared with previous inter-pandemic seasons. Nevertheless, in Spain the 2009 pandemic was characterized as mild, considering the duration of the pandemic period and the influenza detection rate, both in the range of those observed in previous inter-pandemic seasons. Also, the case fatality ratio (CFR) was estimated at 0.58 deaths/1,000 confirmed ILI cases (95%CI, 0.52-0.64), in the range of the two previous pandemics of 1957 and 1968, with the highest CFR observed in the older than 64 years age group. In the 2009 pandemic there was a higher percentage of pandemic confirmed deaths in the younger ages, compared to seasonal influenza, since only 28% of the reported deaths occurred in persons aged 64 years and older.

INFECCIÓN ASINTOMÁTICA POR EL VIRUS INFLUENZA H1N1(2009) EN PERSONAL SANITARIO. ESTUDIO MARBEGRIP. RESULTADOS PRELIMINARES

Fundamento: La proporcion de individuos asintomaticos que se infectan por gripe AH1N1v varia segun las series. Los sanitarios estan expuestos al virus de la gripe AH1N1v por su condicion laboral, por lo que cabe esperar una prevalencia elevada de individuos con serologia positiva sin presentar cuadro clinico asociado. El objetivo del estudio fue determinar la prevalencia de sanitarios asintomaticos con serologia positiva para el virus de la gripe AH1N1v. Metodos: Se propuso un estudio prospectivo de cohortes en personal hospitalario en funcion de un hipotetico gradiente decreciente de exposicion al virus: personal de urgencias, area medica, area quirurgica y celadores no de urgencias. Se extrajo sangre de los participantes en septiembre-octubre de 2009, noviembre-diciembre de 2009 y en abril-mayo de 2010, junto con la extraccion se rellenaba un cuestionario de salud. Se ofrecio la participacion voluntaria a los miembros de los diferentes servicios. En sangre se procedio a determinar anticuerpos especificos frente al virus de la gripe AH1N1v por medio de inhibicion de la hemaglutinacion. Participaron 18 hospitales con un total de 1.371 participantes. Resultados: Se dispone de cuestionario de salud y de resultados serologicos de cuatro hospitales. Se observo una proporcion variable de sanitarios asintomaticos con serologia positiva sin haber sido vacunados (entre el 5,6% y el 83%). Solo se vacunaron un 19,4% de los sanitarios, con un porcentaje de serologias positivas tambien variable (entre un 18,8% y 64,7%). El porcentaje de serologias positivas fue significativamente menor entre los celadores y el resto de categorias profesionales. La vacunacion fue mayor entre los medicos que en el resto de estamentos profesionales. Conclusiones: Existe un porcentaje variable de individuos con serologia positiva sin haber sufrido sintomas, con claras diferencias geograficas. Se observan tambien diferencias en la efectividad vacunal en terminos serologicos.The proportion of asymptomatic individuals infected by influenza AH1N1v varies depending on the studies. Health personnel were exposed to the AH1N1v virus due to their professional activity, thus an high seroprevalence to the virus could be expected in the absence of symptomatology. The objective of this study was to determine the prevalence of asymptomatic individuals serologically positive for influenza AH1N1v virus.A cohort based prospective study on hospital staff was proposed according to an hypothetic decreasing gradient of exposure to the virus, from emergency personnel to medical and surgical areas, and auxiliary staff other than emergency personnel. Serum sample from each participant was taken in September-October, 2009, November-December, 2009, and in April-May, 2010; and a health questionnaire was simultaneously filled out. Specific antibodies against influenza AH1N1v were detected by hemagglutination inhibition test. Eighteen hospitals (1,371 individuals) participated in the study.Health questionnaire and serological results from four hospitals are available. A variable proportion of non vaccinated individuals showed positive serology (5.6-83%). Only 19.4% of subjects received vaccine, with a variable rate of positive serology (18.8-64.7%). Positive serology was significantly lower in non medical participants. In addition, vaccine coverage was higher in medical personnel than in the rest of professional categories.There was a variable percentage of influenza AH1N1v seropositive individuals who had not suffered clinical symptomatology. This serological study detects differences on vaccine efficacy.BACKGROUND The proportion of asymptomatic individuals infected by influenza AH1N1v varies depending on the studies. Health personnel were exposed to the AH1N1v virus due to their professional activity, thus an high seroprevalence to the virus could be expected in the absence of symptomatology. The objective of this study was to determine the prevalence of asymptomatic individuals serologically positive for influenza AH1N1v virus. METHODS A cohort based prospective study on hospital staff was proposed according to an hypothetic decreasing gradient of exposure to the virus, from emergency personnel to medical and surgical areas, and auxiliary staff other than emergency personnel. Serum sample from each participant was taken in September-October, 2009, November-December, 2009, and in April-May, 2010; and a health questionnaire was simultaneously filled out. Specific antibodies against influenza AH1N1v were detected by hemagglutination inhibition test. Eighteen hospitals (1,371 individuals) participated in the study. RESULTS Health questionnaire and serological results from four hospitals are available. A variable proportion of non vaccinated individuals showed positive serology (5.6-83%). Only 19.4% of subjects received vaccine, with a variable rate of positive serology (18.8-64.7%). Positive serology was significantly lower in non medical participants. In addition, vaccine coverage was higher in medical personnel than in the rest of professional categories. CONCLUSIONS There was a variable percentage of influenza AH1N1v seropositive individuals who had not suffered clinical symptomatology. This serological study detects differences on vaccine efficacy.

Pneumococcal pneumonia in preschool children: viral coinfection does not worsen clinical outcome.

To the Editors: We read with interest the article by Techasaensiri et al, which analyzed the effect of viral coinfection on the clinical and laboratory characteristics, and outcome of 129 patients with invasive pneumococcal disease. It is believed that viral infections in pneumococcal pneumonia appear to be associated with more severe clinical disease. Between December 2006 and December 2008, we performed a prospective study on hospitalized children at the Hospital Infantil Niño Jesus of Madrid, who had acute community-acquired pneumonia. Previously healthy, children aged 2 to 6 years were considered eligible for inclusion. Etiologic studies included blood culture; pneumococcal DNA detection in blood samples by real-time polymerase chain reaction (RT-PCR), as described by Tarrago et al; and viral serologic conversion in paired serum samples. Three RT-nested PCR assays were performed in nasopharyngeal samples to detect a total of 16 respiratory viruses: influenza virus A, B, and C were detected using previously described primer sets only to amplify influenza viruses; a second multiplex PCR was used to detect parainfluenza viruses 1 to 4, human coronaviruses 229E and OC43, enteroviruses, and rhinoviruses; the presence of respiratory syncytial virus-A and B types, hMPV, HBoV, and adenoviruses was investigated by a third multiplex RT-nested PCR. Patients who needed thoracocentesis were admitted to the pediatric intensive care unit. The study of the pleural fluid included microbiologic cultures, Gram staining, antigen testing (Binax Now), and RT-PCR for Streptococcus pneumoniae. This study was approved by the ethical committee of our institution, and signed consent forms were obtained from informed parents. Pneumococcal pneumonia was diagnosed in 83 patients, on the basis of blood cultures (11), RT-PCR (71), or pleural liquid studies (16). Quantitative procalcitonin samples were obtained in 74 cases, and serology paired samples were done in 62 cases. Viral coinfections were found in 49 patients (59%): 25 patients with 1 virus, 18 patients with 2 viruses, and 6 patients with 3 viruses. The most common viruses identified were rhinovirus (28), respiratory syncytial virus (11), and adenovirus (11). As Techasaensiri et al reported, we did not find significant differences when comparing the clinical and laboratory characteristics of patients with positive versus negative viral tests (Table, Supplemental Digital Content 1, http://links.lww.com/INF/A672). Length of stay, pediatric intensive care unit admission, and development of pleural effusion were not influenced by the presence of viral coinfection. It is remarkable that none of the patients with respiratory syncytial virus developed pleural effusion. There were no deaths among our patients. In contrast to the study of Techasaensiri et al, we included only patients with pneumonia, preschool age, and without any known underlying medical condition. Our results indicate that viral coinfection in pneumococcal pneumonia had no influence on clinical manifestations, laboratory characteristics, and patient outcome. Javier Alvarez-Coca Gonzalez, MD, PhD Jorge Martinez Perez, MD Seccion de Pediatria, Hospital Infantil Niño Jesus

Biodefensa: un nuevo desafío para la microbiología y la salud pública

Bioterrorism and the potential use of biological weapons has become an important concern of governments and responsible authorities. An example of this threat occurred in 2001 in the USA, when letters were sent containing spores of the agent that produces anthrax; this resulted in some deaths, and caused panic and negative effects on the world economy. If this small-scale event was able to cause such a huge impact, the repercussions of a massive attack could be catastrophic. In many countries, these events have resulted in the implementation of measures directed toward preventing and responding to bioterrorist threats and acts. As a whole, these measures are known as biodefense. This article briefly analyzes several aspects related to detecting and identifying acts of bioterrorism, and considers the biological agents that are implicated. The microbiological diagnosis that allows identification of the causal agent, a key point for taking suitable control measures, is also included.

Asymptomatic Infection by Influenza AH1N1 Virus in Healthcare Workers: MARBEGRIP Study, Preliminar Results

Fundamento: La proporcion de individuos asintomaticos que se infectan por gripe AH1N1v varia segun las series. Los sanitarios estan expuestos al virus de la gripe AH1N1v por su condicion laboral, por lo que cabe esperar una prevalencia elevada de individuos con serologia positiva sin presentar cuadro clinico asociado. El objetivo del estudio fue determinar la prevalencia de sanitarios asintomaticos con serologia positiva para el virus de la gripe AH1N1v. Metodos: Se propuso un estudio prospectivo de cohortes en personal hospitalario en funcion de un hipotetico gradiente decreciente de exposicion al virus: personal de urgencias, area medica, area quirurgica y celadores no de urgencias. Se extrajo sangre de los participantes en septiembre-octubre de 2009, noviembre-diciembre de 2009 y en abril-mayo de 2010, junto con la extraccion se rellenaba un cuestionario de salud. Se ofrecio la participacion voluntaria a los miembros de los diferentes servicios. En sangre se procedio a determinar anticuerpos especificos frente al virus de la gripe AH1N1v por medio de inhibicion de la hemaglutinacion. Participaron 18 hospitales con un total de 1.371 participantes. Resultados: Se dispone de cuestionario de salud y de resultados serologicos de cuatro hospitales. Se observo una proporcion variable de sanitarios asintomaticos con serologia positiva sin haber sido vacunados (entre el 5,6% y el 83%). Solo se vacunaron un 19,4% de los sanitarios, con un porcentaje de serologias positivas tambien variable (entre un 18,8% y 64,7%). El porcentaje de serologias positivas fue significativamente menor entre los celadores y el resto de categorias profesionales. La vacunacion fue mayor entre los medicos que en el resto de estamentos profesionales. Conclusiones: Existe un porcentaje variable de individuos con serologia positiva sin haber sufrido sintomas, con claras diferencias geograficas. Se observan tambien diferencias en la efectividad vacunal en terminos serologicos.The proportion of asymptomatic individuals infected by influenza AH1N1v varies depending on the studies. Health personnel were exposed to the AH1N1v virus due to their professional activity, thus an high seroprevalence to the virus could be expected in the absence of symptomatology. The objective of this study was to determine the prevalence of asymptomatic individuals serologically positive for influenza AH1N1v virus.A cohort based prospective study on hospital staff was proposed according to an hypothetic decreasing gradient of exposure to the virus, from emergency personnel to medical and surgical areas, and auxiliary staff other than emergency personnel. Serum sample from each participant was taken in September-October, 2009, November-December, 2009, and in April-May, 2010; and a health questionnaire was simultaneously filled out. Specific antibodies against influenza AH1N1v were detected by hemagglutination inhibition test. Eighteen hospitals (1,371 individuals) participated in the study.Health questionnaire and serological results from four hospitals are available. A variable proportion of non vaccinated individuals showed positive serology (5.6-83%). Only 19.4% of subjects received vaccine, with a variable rate of positive serology (18.8-64.7%). Positive serology was significantly lower in non medical participants. In addition, vaccine coverage was higher in medical personnel than in the rest of professional categories.There was a variable percentage of influenza AH1N1v seropositive individuals who had not suffered clinical symptomatology. This serological study detects differences on vaccine efficacy.BACKGROUND The proportion of asymptomatic individuals infected by influenza AH1N1v varies depending on the studies. Health personnel were exposed to the AH1N1v virus due to their professional activity, thus an high seroprevalence to the virus could be expected in the absence of symptomatology. The objective of this study was to determine the prevalence of asymptomatic individuals serologically positive for influenza AH1N1v virus. METHODS A cohort based prospective study on hospital staff was proposed according to an hypothetic decreasing gradient of exposure to the virus, from emergency personnel to medical and surgical areas, and auxiliary staff other than emergency personnel. Serum sample from each participant was taken in September-October, 2009, November-December, 2009, and in April-May, 2010; and a health questionnaire was simultaneously filled out. Specific antibodies against influenza AH1N1v were detected by hemagglutination inhibition test. Eighteen hospitals (1,371 individuals) participated in the study. RESULTS Health questionnaire and serological results from four hospitals are available. A variable proportion of non vaccinated individuals showed positive serology (5.6-83%). Only 19.4% of subjects received vaccine, with a variable rate of positive serology (18.8-64.7%). Positive serology was significantly lower in non medical participants. In addition, vaccine coverage was higher in medical personnel than in the rest of professional categories. CONCLUSIONS There was a variable percentage of influenza AH1N1v seropositive individuals who had not suffered clinical symptomatology. This serological study detects differences on vaccine efficacy.

Gripe pandémica H1N1 (2009): experiencia de la Red de Laboratorios de Gripe del Sistema de Vigilancia de la Gripe en España (SVGE)

Existen tres tipos de virus de la gripe: A, B y C. Estos virus evolucionan constantemente debido a que presentan dos caracteristicas principales, la primera es la falta de capacidad correctora de la polimerasa viral que hace que se acumulen mutaciones puntuales en sus genes (deriva antigenica), y la segunda la naturaleza de su genoma formando por ocho segmentos lo que le permite el intercambio de genes entre distintos virus (salto antigenico). Esta plasticidad viral ha permitido que los virus de la gripe A sean capaces de adaptarse a diferentes hospedadores y adquirir capacidades pandemicas. El sistema de vigilancia de la gripe en Espana (SVGE) surgio como respuesta a la preocupacion de que se produjera una pandemia, maxime despues de los casos de gripe aviar detectados en el ser humano. Este sistema de vigilancia esta formado por dieciseis redes de medicos generales y pediatras centinela y diecinueve servicios de epidemiologia, coordinados por el Centro Nacional de Epidemiologia (CNE) y una red de dieciocho laboratorios, la red de laboratorios de Espanoles de Gripe (ReLEG), coordinados por el Centro Nacional de Microbiologia (CNM). El objetivo de este articulo es presentar la actuacion de la ReLEG durante la pandemia producida por el virus de la gripe (H1N1)2009, durante la temporada 2009-2010. La funcion principal de la red es la vigilancia de los virus circulantes mediante su deteccion y posterior caracterizacion genetica y antigenica, incluyendo la deteccion de las mutaciones de resistencia que afectan a los farmacos en uso, principalmente el Oseltamivir.