Anna Martínez

D225G mutation in the hemagglutinin protein found in 3 severe cases of 2009 pandemic influenza A (H1N1) in Spain.

From 27 April to 16 December 2009, we analyzed the hemagglutinin gene sequence of 2009 pandemic influenza A (H1N1) virus in 189 respiratory specimens. We only found the D225G mutation in 3 severe cases. However, it was not found in samples from other cases with or without clinical criteria of severity. The biologic significance of this mutation remains still unclear.

Influenza C virus surveillance during the first influenza A (H1N1) 2009 pandemic wave in Catalonia, Spain

Although particular attention is paid to influenza A and B virus isolates during influenza surveillance, influenza C virus (FLUCV) coexisted during the first influenza A (H1N1) 2009 pandemic wave during the 2009-2010 season. From 27 April 2009 to 9 May 2010, 12 strains of FLUCV were detected in specimens collected from 1713 nonhospitalized patients with upper respiratory tract illness using a molecular method. Half of the patients with FLUCV infection were older than 14 years. The most frequent symptoms were cough and fever, similar to other viral respiratory infections. Phylogenetic analysis of the hemagglutinin-esterase gene revealed that the strains belonged to the C/Kanagawa/1/76-related and C/Sao Paulo/378/82-related lineages, demonstrating their co-circulation in Catalonia. In addition to regular virological surveillance that provides information about the incidence and the exact role of FLUCV in acute viral respiratory infections in the general population, the genetic lineage identification offers additional data for epidemiological purposes.

Acute gastroenteritis outbreaks in Catalonia, Spain: Norovirus versus Salmonella

Objective. To describe the epidemiology of norovirus (NV) and Salmonella gastroenteritis outbreaks in Catalonia between 15 October 2004 and 30 October 2005. Material and methods. Epidemiological data were obtained from outbreak reports. The aetiologic agent was investigated by culture for enteric bacteria, enzyme immunoanalyses, reverse transcription polymerase chain reaction (RT-PCR) and molecular epidemiology genotyping for NV. The χ2 test was used to compare proportions. Incidence rates and their confidence intervals (CI) were calculated assuming a Poisson distribution. Results. A total of 225 acute gastroenteritis (AG) outbreaks were reported, with 3436 persons affected and 115 hospitalized. Sixty outbreaks (27%) accounting for 1791 cases (52%) were caused by NV, with an attack rate (AR) of 34.7% and a hospitalization rate (HR) of 0.2%. Seventy- four outbreaks (33%) were caused by Salmonella spp., affecting 646 persons (18.8% (AR 45.6% and HR 13.7%)). The difference in AR between Salmonella spp. and NV was statistically significant (odds ratio (OR) 1.57; 95% CI: 1.39–1.78; p <0.001). The median number of affected persons per outbreak was 3-fold higher for NV (15 (2–174)) than for Salmonella (5 (2–44)). The incidence rate of AG cases associated with NV outbreaks was significantly higher (24.9 per 100,000 persons/year (95% CI: 23.7–26.1)) than for those associated with Salmonella (5(2–44)) outbreaks (9.2 per 100,000 persons/year (95% CI: 8.5–9.9)). Conclusions. The disease burden and impact of NV highlight the importance of timely notification and investigation of outbreaks and the development and implementation of preventive measures, such as health and safety education for caregivers and food handlers in order to reduce the incidence of infections.

Vigilancia virológica de la gripe 2001-2002

Resumen Fundamento Las caracteristicas biologicas que poseen los virus de la gripe, en particular el del tipo A, que presenta cambios antigenicos constantes, condicionan que gran parte de la poblacion sea susceptible a la gripe, por lo que se presentan anualmente epidemias de intensidad variable. En este estudio se presentan los resultados de un programa de vigilancia virologica cuyo objetivo fue detectar de forma temprana el inicio de la epidemia e identificar los virus circulantes. Metodos Entre los meses de noviembre de 2001 y abril de 2002, 23 equipos de atencion primaria distribuidos en las provincias de Girona, Barcelona y Tarragona recogieron muestras del exudado nasal y faringeo de pacientes que presentaban sindrome gripal o infeccion respiratoria aguda. Se practico inmunofluorescencia y cultivo celular de las muestras obtenidas. Se investigo la presencia de virus de la gripe A, B (VGA y VGB), virus respiratorio sincitial (VRS), virus parainfluenza 1, 2 y 3 (VP 1, VP 2, VP 3) y adenovirus (ADV). Resultados Se estudiaron 472 muestras de las que 172 (36%) fueron positivas: 97 a VGA; 59 a VGB; 10 a VRS; 5 a ADV y 1 a VP 3. La fiebre y el inicio brusco se presentaron de forma mas frecuente en los pacientes en los que se detecto VGA o VGB que en los que no se detecto (el 91% y el 72% frente al 65 y el 59%) siendo las diferencias estadisticamente significativas (p Conclusion Durante las 13 semanas que ha durado la epidemia gripal se ha producido un incremento muy notable en el porcentaje de positividad de las muestras para los virus de la gripe A y B. Este hecho ha resultado de gran utilidad para la deteccion temprana y el seguimiento adecuado de la epidemia.

Vigilancia de la de gripe pandémica (H1N1) 2009 en Cataluña: Resultados e implicaciones

BACKGROUND Pandemics require an assessment of its severity. The objective was to determine the characteristics of pandemic influenza in Catalonia. METHODS We conducted a surveillance study on the incidence of ILI and severe cases between June 2009 and May 2010. A network of 55 doctors reported influenza-like illness and collected nasopharyngeal swabs. The severity of the pandemic was assessed through severe cases confirmed.We calculated the lethality and incidence rates and mortality. The differences are studied with the relative risk (RR) with confidence intervals (CI) of 95%. RESULTS The incidence of ILI was much higher in the 5 to 14 and from 0 to 4 years old (1227.8 and 1048.4, respectively, in the week of maximum incidence). Of positive samples, 52.4% (477/916) were positive for influenza virus and the majority, 456 (95.6%) were the pandemic influenza virus (H1N1) 2009.The incidence of severe cases was 10.3 per 10(5) and was higher in children (14,5) and adults under 65 years (10,2) (p < 0.0001). Overall mortality was 0.7 per 10(5) and was also higher in children and adults under 65 but the differences were not statistically significant. The fatality rate was estimated at 0.03% and was much higher in the 15 to 44 years (0,03%) (RR = 3.1, 95% CI 1.2 to 8.3), 45 to 64 years (0,11%) (RR = 11.9 95% CI 4.3 to 32.7) and over 64 years (0,73%) (RR = 79.6, 95% CI 25.3 to 250.9) compared to group 5 to 14 years (0,01%). CONCLUSIONS The incidence of severe hospitalized cases was similar to or lower than that observed in the southern hemisphere. The lower risk of hospitalization in people over 64 years suggests the relative protection of this age group against the pandemic virus.Fundamentos. Las pandemias requieren una valoracion de su nivel de gravedad. El objetivo fue determinar las caracteristicas de la gripe pandemica en Cataluna. Metodos. Se realizo un estudio de vigilancia sobre la incidencia de sindromes gripales y casos graves entre junio del 2009 y mayo del 2010. Una red de 55 medicos notificaron los sindromes gripales y recogieron frotis nasofaringeos. La gravedad de la pandemia se valoro a traves de casos graves confirmados. Se calcularon la letalidad y las tasas de incidencia y de mortalidad. La existencia de diferencias se estudio con el Riesgo Relativo (RR) y su intervalo de confianza (IC) del 95%. Resultados: La incidencia de sindromes gripales fue muy superior en el grupo de 5 a 14 y de 0 a 4 anos (1227,8 y 1048,4 respectivamente, en la semana de maxima incidencia). De las muestras positivas 477 (52,4%) fueron positivas a virus gripal y la mayoria, 456 (95,6%) lo fueron al virus gripal pandemico A (H1N1) 2009. La incidencia de casos graves fue de 10,3 por 10(5) y fue superior en ninos (14,5) y adultos menores de 65 anos (10,2) (p<0,0001). La mortalidad global fue del 0,7 por 10(5) y fue tambien superior en ninos (0,8) y adultos menores de 65 anos (0,7) pero las diferencias no fueron estadisticamente significativas. La letalidad estimada fue de 0,03% y fue muy superior en el grupo de 15 a 44 anos (0,03%) (RR=3,1; IC95% 1,2-8,3), de 45 a 64 anos (0,11%) (RR=11,9; IC95% 4,3-32,7) y mayores de 64 anos (0,73%) (RR=79,6; IC95% 25,3-250,9) respecto al grupo de 5 a 14 anos (0,01%). Conclusiones: La incidencia de casos graves hospitalizados fue similar o inferior a la observada en el hemisferio sur. El riesgo inferior de hospitalizacion en los mayores de 64 anos sugiere proteccion relativa de este grupo de edad frente al virus pandemico.

Hepatitis A outbreaks: the effect of a mass vaccination programme

Summary.  A Hepatitis A vaccination programme of people belonging to risk groups begun in Catalonia in 1995 and a universal vaccination programme of pre‐adolescents 12 years of age with the hepatitis A + B vaccine was added in 1998. The aim of the study was to investigate the characteristics of hepatitis A outbreaks occurring in Catalonia between 1991 and 2007 to determine the associated risk factors and optimize the use of vaccination. Incidence rates of outbreaks, cases and hospitalizations associated with outbreaks and the rate ratios (RR) of person‐to‐person transmission outbreaks between the periods before and after mass vaccination and their 95% confidence intervals (CI) were calculated. A rate of 2.45 outbreaks per million persons per year was found. The rate of cases affected in these outbreaks was 1.28 per 105 persons per year and the rate of hospitalizations was 0.45 per million persons per year. In person‐to‐person outbreaks, the highest incidence rate (5.26 and 6.33 per million persons per year) of outbreaks according to the age of the index case was in the 5 to 14 year age group in both periods (RR:0.83; 95% CI:0.48–1.43). A significant increase was observed in the 25 to 44 year age group (RR: 0.35; 95% CI 0.14–0.77). Hepatitis A vaccination has made an important impact on burden and characteristics of outbreaks and could provide greater benefits to the community if the vaccine was administrated to children during their first years of life.

Lack of detection of Middle East respiratory syndrome coronavirus in mild and severe respiratory infections in Catalonia, northeastern Spain

Abstract Surveillance of Middle East respiratory syndrome coronavirus (MERS-CoV) was conducted to explore the possible introduction and circulation of this novel virus in Catalonia, northeastern Spain. Five hundred and sixty-three samples from mild and severe respiratory infections collected between January 2012 and April 2013 were screened using real-time RT-PCR. All samples were negative, suggesting that MERS-CoV is not circulating silently in Catalonia.

Factores asociados a la transmisión a los convivientes de gripe (H1N1) 2009

Factors associated with household transmission of Influenza (H1N1)2009 Bakcground: A good part of the transmission of influenza occurs in the household context. The main objective of this study was to evaluate the factors associated with the index cases generating secondary cases in household. Methods: We designed an observational, retrospective, multicenter through the implementation of a telephone survey in three regions of Spain. The study population were hospitalized and outpatient cases of confirmed H1N1 (2009) reported to the surveillance units from week 44 of 2009. We calculated the secondary attack rate within the household (TAI) and confidence interval of 95!. Factors associated with household transmission were analyzed by logistic regression, calculating odds ratios and confidence intervals at 95!. Results: the secundary attack rate was 11.3! (95! CI 9.9 to 12.7) within the household. The number of household contacts was the main factor associated with the transmission (OR: 5,02 CI95! 1,78-14,13). Conclussion: The factor most associated with the generation of secondary cases is the family size, being greater the larger the group of cohabiting, which is consistent with the data provided by WHO.BACKGROUND A good part of the transmission of influenza occurs in the household context. The main objective of this study was to evaluate the factors associated with the index cases generating secondary cases in household. METHODS We designed an observational, retrospective, multicenter through the implementation of a telephone survey in three regions of Spain. The study population were hospitalized and outpatient cases of confirmed H1N1 (2009) reported to the surveillance units from week 44 of 2009. We calculated the secondary attack rate within the household (TAI) and confidence interval of 95%. Factors associated with household transmission were analyzed by logistic regression, calculating odds ratios and confidence intervals at 95%. RESULTS the secondary attack rate was 11.3% (95% CI 9.9 to 12.7) within the household. The number of household contacts was the main factor associated with the transmission (OR: 5,02 CI95% 1,78-14,13). CONCLUSION The factor most associated with the generation of secondary cases is the family size, being greater the larger the group of cohabiting, which is consistent with the data provided by WHO.

Aspectos virológicos de la vigilancia de la gripe

Fundamento Las caracteristicas biologicas que poseen los virus de la gripe, en particular el del tipo A, que presenta cambios antigenicos constantes, condicionan que gran parte de la poblacion sea susceptible a la gripe, por lo que se presentan anualmente epidemias de intensidad variable. En este estudio se presentan los resultados de un programa de vigilancia virologica cuyo objetivo fue detectar precozmente el inicio de la epidemia e identificar los virus circulantes. Metodos Durante los meses de noviembre de 1999 a abril de 2000, 22 equipos de Atencion Primaria distribuidos por las provincias de Girona, Barcelona y Tarragona recogieron muestras del exudado faringeo de pacientes que presentaban sindrome gripal. Se practico inmunofluorescencia y cultivo celular a las muestras obtenidas. Se investigo la presencia de virus de la gripe A, B (VGA y VGB), virus respiratorio sincitial (VRS), virus parainfluenza 1,2 y 3 (VP1, VP2, VP3) y adenovirus. Resultados Se estudiaron 879 muestras, de las que 297 (33,7%) resultaron positivas a VGA, diez a VRS, una a VP1, una a adenovirus y una a VGB. La sensibilidad de la tecnica de inmunofluorescencia para el diagnostico de la infeccion por VGA fue de 97% y la de la tecnica de aislamiento virico en cultivo celular 11%. La fiebre y la cefalea se presentaron mas frecuentemente en los pacientes en los que se detecto VGA que en los que no se detecto (67% y 50% frente al 57% y 38%), siendo las diferencias estadisticamente significativas (p = 0,006 y 0,001, respectivamente). No se observaron diferencias significativas de las manifestaciones clinicas entre ninos y adultos. Conclusion Durante las seis semanas que ha durado la epidemia gripal se ha producido un incremento muy notable en el porcentaje de positividad de las muestras para el virus de la gripe A, que ha sido superior al 40% en todas ellas. Este hecho ha resultado de gran utilidad para la deteccion precoz y seguimiento adecuado de la epidemia.

Epidemiología de la enfermedad meningocócica por serogrupo C en Cataluña, 1997-2004

Resumen Introduccion A raiz del aumento en el numero de casos de enfermedad meningococica por serogrupo C en el periodo 1995-1997 se realizaron diferentes campanas de vacunacion en Cataluna. En este trabajo se presenta la evolucion de la enfermedad meningococica por serogrupo C en Cataluna desde el ano 1997 hasta la actualidad. Metodos Se analizaron todos los casos declarados desde 1997 hasta 2004 al sistema EDO (de enfermedades de declaracion obligatoria) y se estimaron las coberturas vacunales alcanzadas en las diferentes campanas de vacunacion. Se calcularon las tasas de incidencia cuatrisemanales durante el periodo de estudio. Resultados Con la primera campana de vacunacion, el ano 1997, se observo un descenso significativo en el numero de casos por serogrupo C en la cohorte de poblacion hasta 19 anos (de 63 a 18 casos en 1998), aunque esta disminucion va desapareciendo rapidamente y en el ano 2000 se notifican ya 27 casos en Conclusiones A la vista de los resultados obtenidos con las diferentes campanas de vacunacion creemos que a partir de ahora los esfuerzos en el control de la enfermedad deberan centrarse en el serogrupo B, sin descuidar por ello la vigilancia del serogrupo C por si hubiera algun cambio en el patron de comportamiento de esta enfermedad que a corto plazo parece controlada con la vacunacion.