S De Mateo

Effectiveness of the 2010–11 seasonal trivalent influenza vaccine in Spain: cycEVA study

BACKGROUND In Spain, the influenza vaccine effectiveness (VE) was estimated in the last three seasons using an observational study (cycEVA) conducted in the frame of the Spanish Influenza Sentinel Surveillance System. We aimed to measure the effectiveness of the seasonal trivalent vaccine in preventing influenza like illness (ILI) laboratory-confirmed influenza infection at the end of the season 2010-11. METHODS We conducted a test-negative case-control study between weeks 50/2010 and 12/2011. Cases were ILI laboratory-confirmed influenza infection and controls were those testing negative. Sentinel physicians collected data on demographic and clinical characteristics, vaccination status, and on covariates related to confounding factors associating with influenza VE. We calculated adjusted odds ratios (OR), using logistic regression and computed influenza VE as (1-OR) × 100. RESULTS The adjusted influenza VE against A(H1N1)pdm09 infection was 46% (95% confidence interval (95%CI): 0; 72). In A(H1N1)pdm09 infected patients who had received both 2010-11 trivalent influenza seasonal and 2009 monovalent pandemic vaccines, influenza VE was 74% (95%CI: 13; 93). The adjusted influenza VE against B infection was 23% (95%CI: -180; 79). CONCLUSION The trivalent influenza vaccine 2010-11 showed a moderate VE for preventing ILI laboratory confirmed influenza infections. Influenza VE estimates were higher in patients who had received both 2010-11 seasonal trivalent and 2009 monovalent pandemic vaccines.

Influenza vaccine effectiveness in Spain 2013/14: subtype-specific early estimates using the cycEVA study.

Adjusted early estimates of the 2013/14 influenza vaccine effectiveness (VE) in Spain for all age groups was 35% (95% CI: -9 to 62), 33% (95% CI: -33 to 67) and 28% (95% CI: -33 to 61) against any influenza virus type, A(H1N1)pdm09 and A(H3N2) viruses, respectively. For the population targeted for vaccination, the adjusted VE was 44% (95% CI: -11 to 72), 36% (95% CI: -64 to 75) and 42% (95% CI: -29 to 74), respectively. These preliminary results in Spain suggest a suboptimal protective effect of the vaccine against circulating influenza viruses.

Outbreak of tularaemia in Castilla y León, Spain

In late June 2007, the Epidemiological Surveillance Network in Castilla y Leon, northern Spain, reported a series of cases in a rural area in the province of Palencia and in the provincial capital city of Leon, labelled as “fever of unknown origin”. Subsequent epidemiological investigation confirmed an outbreak of tularaemia.

Heterogeneous trend in smoking prevalence by sex and age group following the implementation of a national smoke-free law

Objective Given the limited evidence available about the effects of clean indoor air laws on smoking behaviour in the general population, the impact of national smoke-free workplace, bar and restaurant legislation, implemented on 1 January 2006, on smoking prevalence in Spain was assessed in this study. Methods Population-based trend analysis using estimates for 27 periods from the beginning of 2000 to the end of 2008—three periods per year. To calculate the period per cent change in smoking prevalence, the permutation test for joinpoint regression to detect significant changes was used. Results In men and women aged 15–24 years, the prevalence of smoking declined between the first period in 2000 and the third period in 2008, whereas in women aged 45–64 years, it increased by 1.7% per period. A declining trend was detected up to the first period in 2006 in men and women aged 25–44 years and in men aged 45–64 years, but between the beginning of 2006 and the end of 2008 the prevalence of smoking increased by 1.2%, 0.7% and 2.0% per period in men aged 25–44 years, in women aged 25–44 years and in men aged 45–64 years, respectively. Conclusions 3 years after a national smoke-free law was implemented, the trend in smoking prevalence in some population groups was unchanged; however, in others, the declining trend of previous years was reversed. The similarity of these findings to those observed in other countries suggests that clean indoor air laws, although effective in reducing exposure to second-hand smoke, may not achieve the secondary objective of reducing the prevalence of smoking in the population.

Sistemas de vigilancia de la salud pública: no pidamos peras al olmo

The publication of the Decree creating the National Epidemiological Surveillance Network, 7 years ago now, invites us to reflect on public health surveillance systems in our country and to highlight those aspects that help or obstruct these systems in meeting their basic objective of providing information that can be used to facilitate disease control. Many of the events that have taken place in the health arena in recent years, labeled as «health crises» by the communications media, have been considered by the population as unacceptable risks that the health system should have avoided; defects in surveillance systems are one of the errors always mentioned in this respect. Some of these defects arise because of limitations of the instruments used to measure and classify health problems, but others are due to an inappropriate understanding of surveillance, which make it difficult to assess the true impact of health problems. A discussion of the two types of defects will not solve surveillance problems, but it may help many people to stop asking our surveillance systems for what they cannot offer.

Estimating influenza vaccine effectiveness in Spain using sentinel surveillance data.

We aimed to estimate influenza vaccine effectiveness (VE) against laboratory-confirmed influenza during three influenza seasons (2010/11 to 2012/2013) in Spain using surveillance data and to compare the results with data obtained by the cycEVA study, the Spanish component of the Influenza Monitoring Vaccine Effectiveness (I-MOVE) network. We used the test-negative case–control design, with data from the Spanish Influenza Sentinel Surveillance System (SISS) or from the cycEVA study. Cases were laboratory-confirmed influenza patients with the predominant influenza virus of each season, and controls were those testing negative for any influenza virus. We calculated the overall and age-specific adjusted VE. Although the number of patients recorded in the SISS was three times higher than that in the cycEVA study, the quality of information for important variables, i.e. vaccination status and laboratory results, was high in both studies. Overall, the SISS and cycEVA influenza VE estimates were largely similar during the study period. For elderly patients (> 59 years), the SISS estimates were slightly lower than those of cycEVA, and estimates for children (0–14 years) were higher using SISS in two of the three seasons studied. Enhancing the SISS by collecting the date of influenza vaccination and reducing the percentage of patients with incomplete information would optimise the system to provide reliable annual influenza VE estimates to guide influenza vaccination policies.

La notificación de casos de enfermedades: Un siglo de tradición

La vigilancia de la salud publica tuvo su origen en el control de las enfermedades infecciosas. Medidas de control, como el aislamiento y la cuarentena, junto a una declaracion imprecisa de casos y muertes en situaciones epidemicas,

Evolución de la mortalidad por enfermedades infecciosas en España

Resumen Objetivo Describir la evolucion temporal y provincial de la mortalidad por enfermedades infecciosas en Espana durante el periodo 1980–1993. Metodos Se han estudiado las defunciones por enfermedades infecciosas ocurridas en Espana durante el periodo 1980-1993. Los datos proceden del registro nacional de mortalidad del Instituto Nacional de Estadistica, y se han incluido tanto las defunciones asignadas al grupo I de la Clasificacion Internacional de Enfermedades como las defunciones por enfermedades infecciosas asignadas al resto de grupos. La evaluacion de la tendencia del riesgo de mortalidad se realizo mediante un analisis de regresion log-lineal de Poisson mientras que las variaciones provinciales en el riesgo de mortalidad se evaluaron con las razones de mortalidad estandarizadas (REM) por edad de las provincias espanolas para los periodos 1980-83 y 1990-93 y, posteriormente, comparando esas REM provinciales de los periodos inicial y final mediante el coeficiente de correlacion de rangos de Spearman. Resultados Entre 1980 y 1993, la tasa de mortalidad ajustada por edad por enfermedades infecciosas experimento un decremento anual medio de 1,4%. Tanto en 1980 como en 1993 las infecciones respiratorias fueron la primera causa de muerte, 29,6 y 20,3 defunciones por 105 habitantes respectivamente. La segunda causa de muerte fue la tuberculosis en 1980, 3,9 × 105 habitantes, y la infeccion por el virus de la inmunodeficiencia humana (VIH) en 1993, 10,7 × 105 habitantes. El descenso de la mortalidad por estas enfermedades durante el periodo estudiado se observo en todos los grupos de edad, a excepcion del grupo de 25 a 44 anos, cuya mortalidad entre 1985 y 1993 se multiplico por siete. Por lo que se refiere a la distribucion provincial, las provincias con mayor mortalidad en 1980-83 presentaron tambien mayor mortalidad en 1990-93 (coeficiente de Spearman: 0,49; p Conclusiones Debido a que las defunciones por enfermedades infecciosas aparecen distribuidas en varios grupos de la CIE, su impacto en la mortalidad es generalmente infravalorado, a pesar de que suponen la cuarta causa de muerte en Espana. No obstante, durante el periodo 1980-93, se ha observado un descenso en la mortalidad por estas enfermedades, con la excepcion del grupo de 25 a 44 anos donde se ha producido un incremento espectacular atribuible a la infeccion por VIH. En cambio, no se han puesto de manifiesto variaciones espaciales a nivel provincial.

Standardisation or modelling of mortality rates.

STUDY OBJECTIVE: To compare the results obtained when estimating a standardised rate using the conventional technique of stratified analysis and using Poisson regression, and to evaluate the speed of the two techniques in making the calculation. DESIGN: Cross sectional study. SETTING AND PARTICIPANTS: The trend in motor vehicle accident mortality in males from 1985 to 1992 in Spain was compared using stratified analysis and Poisson regression. In the stratified analysis the calculations were made using a specially designed spreadsheet while in the Poisson regression the statistical program used was EGRET. RESULTS: The stratified analysis took two hours and the Poisson regression 15 minutes to complete. In the stratified analysis a single estimate for each year was obtained, whereas the model of Poisson regression that best fitted the data included an interaction term between age and year. CONCLUSION: Poisson regression can be considered a serious alternative to stratified analysis when the objective is to compare mortality rates standardised by one or two variables.

Public health surveillance systems: let's not ask for the impossible

The publication of the Decree creating the National Epidemiological Surveillance Network, 7 years ago now, invites us to reflect on public health surveillance systems in our country and to highlight those aspects that help or obstruct these systems in meeting their basic objective of providing information that can be used to facilitate disease control. Many of the events that have taken place in the health arena in recent years, labeled as health crises by the communications media, have been considered by the population as unacceptable risks that the health system should have avoided; defects in surveillance systems are one of the errors always mentioned in this respect. Some of these defects arise because of limitations of the instruments used to measure and classify health problems, but others are due to an inappropriate understanding of surveillance, which make it difficult to assess the true impact of health problems. A discussion of the two types of defects will not solve surveillance problems, but it may help many people to stop asking our surveillance systems for what they cannot offer.