Do Saharan Dust Days Carry a Risk of Hospitalization From Respiratory Diseases for Citizens of the Canary Islands (Spain)? / ¿Los días de calima sahariana conllevan un riesgo de hospitalización por enfermedades respiratorias para los ciudadanos de las Islas Canarias, España?

Background: Saharan dust meets the Canary Islands at the beginning of its westward path across the North Atlantic, exceeding the European daily levels for PM10; for this reason, their two provincial capital cities, constitute optimal sites where to evaluate the health effects of this natural event. Objectives: To assess the short-term association between Saharan Dust Days (SDDs) and respiratory morbidity in the two capital cities. Methods: We carried out a time-series analysis with daily emergency hospital admissions due to all respiratory system diseases, chronic obstructive pulmonary disease (COPD) and asthma between 2001 and 2005, assessing the independent effect of SDDs, defined according to the application of the methodology accepted by the European Environmental Office. We also examined accumulated effect, and some other specific SDDs’ features. Results: We found a short-term association between SDDs and the increase in admission risk for the three outcomes during concurrent SDDs, compared to non-SDDs, that spread from 0 to 5th day: 22.6% (95% confidence interval [CI], 10.4, 36.0) for all respiratory diseases and 29.9% (95%CI: 6.6, 58.4) for COPD in Santa Cruz de Tenerife, and 33.4% (95%CI: −2.1,82.0) for asthma in Las Palmas de Gran Canaria. We obtained a robust association when Saharan dust transported at low altitude, when SDDs belonged to long episodes (≥5days), from the fifth SDD onwards and those SDDs with medium (50

Contexto general: El polvo del Sahara se encuentra con las Islas Canarias al comienzo de su viaje en dirección oeste atravesando el Atlántico Norte; esto hace que se superen los niveles límite diarios europeos de PM10. Por este motivo, sus 2 capitales de provincia constituyen entornos óptimos para evaluar los efectos de este fenómeno natural en la salud. Objetivos: Evaluar la asociación a corto plazo entre los días de calima sahariana (DCS) y la morbilidad respiratoria en las 2 ciudades. Métodos: Llevamos a cabo un análisis de series temporales con los ingresos hospitalarios urgentes diarios debido a todas las enfermedades del sistema respiratorio, enfermedad pulmonar obstructiva crónica (EPOC) y asma entre 2001 y 2005, evaluando el efecto independiente de los DCS, que definimos siguiendo la aplicación de la metodología aceptada por la Oficina Europea del Medio Ambiente. También estudiamos el efecto acumulado y otras características específicas de los DCS. Resultados: Encontramos una asociación a corto plazo entre los DCS y el aumento en el riesgo de ingreso para las 3 variables durante los DCS concurrentes, en comparación con los no DCS, que se extendía desde 0 a los 5 días: 22,6% (intervalo de confianza [IC] del 95%: 10,4-36,0) para todas las enfermedades respiratorias, el 29,9% (IC 95%: 6,6-58,4) para la EPOC en Santa Cruz de Tenerife y el 33,4% (IC 95%: −2,1-82,0) para asma en Las Palmas de Gran Canaria. Obtuvimos una asociación fuerte cuando el polvo del Sahara se transportaba a baja altitud, cuando los DCS formaban parte de episodios largos (≥5 días), desde el quinto DCS en adelante y aquellos DCS con niveles de PM10 medios (50

Do Saharan Dust Days Carry a Risk of Hospitalization From Respiratory Diseases for Citizens of the Canary Islands (Spain)?

BACKGROUND: Saharan dust meets the Canary Islands at the beginning of its westward path across the North Atlantic, exceeding the European daily levels for PM10; for this reason, their two provincial capital cities, constitute optimal sites where to evaluate the health effects of this natural event. OBJECTIVES: To assess the short-term association between Saharan Dust Days (SDDs) and respiratory morbidity in the two capital cities. METHODS: We carried out a time-series analysis with daily emergency hospital admissions due to all respiratory system diseases, chronic obstructive pulmonary disease (COPD) and asthma between 2001 and 2005, assessing the independent effect of SDDs, defined according to the application of the methodology accepted by the European Environmental Office. We also examined accumulated effect, and some other specific SDDs' features. RESULTS: We found a short-term association between SDDs and the increase in admission risk for the three outcomes during concurrent SDDs, compared to non-SDDs, that spread from 0 to 5th day: 22.6% (95% confidence interval [CI], 10.4, 36.0) for all respiratory diseases and 29.9% (95%CI: 6.6, 58.4) for COPD in Santa Cruz de Tenerife, and 33.4% (95%CI: -2.1,82.0) for asthma in Las Palmas de Gran Canaria. We obtained a robust association when Saharan dust transported at low altitude, when SDDs belonged to long episodes (≥5days), from the fifth SDD onwards and those SDDs with medium (50

Do Saharan Dust Days Carry a Risk of Hospitalization From Respiratory Diseases for Citizens of the Canary Islands (Spain)?

BACKGROUND: Saharan dust meets the Canary Islands at the beginning of its westward path across the North Atlantic, exceeding the European daily levels for PM10; for this reason, their two provincial capital cities, constitute optimal sites where to evaluate the health effects of this natural event. OBJECTIVES: To assess the short-term association between Saharan Dust Days (SDDs) and respiratory morbidity in the two capital cities. METHODS: We carried out a time-series analysis with daily emergency hospital admissions due to all respiratory system diseases, chronic obstructive pulmonary disease (COPD) and asthma between 2001 and 2005, assessing the independent effect of SDDs, defined according to the application of the methodology accepted by the European Environmental Office. We also examined accumulated effect, and some other specific SDDs' features. RESULTS: We found a short-term association between SDDs and the increase in admission risk for the three outcomes during concurrent SDDs, compared to non-SDDs, that spread from 0 to 5th day: 22.6% (95% confidence interval [CI], 10.4, 36.0) for all respiratory diseases and 29.9% (95%CI: 6.6, 58.4) for COPD in Santa Cruz de Tenerife, and 33.4% (95%CI: -2.1,82.0) for asthma in Las Palmas de Gran Canaria. We obtained a robust association when Saharan dust transported at low altitude, when SDDs belonged to long episodes (≥5days), from the fifth SDD onwards and those SDDs with medium (50

Characterizing mortality effects of particulate matter size fractions in the two capital cities of the Canary Islands.

Most of the studies differentiating the effect of size-classified particulate matter (PM) exposure have been carried out in cities where the average levels of fine particles (PM(2.5)) were higher than those of coarse particles (PM(10-2.5)). These studies have suggested that PM(2.5) is associated with daily mortality, but there is only limited evidence that PM(10-2.5) is independently associated with mortality. The citizens of the Canary Islands are exposed to PM which is highly influenced by mineral dust because of the islands' proximity to the Western Coast of Morocco. This offers an excellent opportunity to analyze in detail the short-term association between PM size fractions and total, respiratory and heart disease mortality. A time-series study from 2001 to 2004 was carried out. For each PM size fraction and mortality outcome, Generalized Additive Poisson Model was performed controlling for potential confounding. Different lag structures, unconstrained distributed lag models and two-pollutant models were examined. After assessing the linearity in the relationship, a piecewise linear analysis for exploring the existence of different slopes for different ranges of PM was carried out. The 10 µg/m(3) increase in PM(2.5) and PM(10-2.5) levels was associated with a 7.5% (95% confidence interval=0.4-15.0) and a 7.4 (95% CI=1.5-13.7) increase in heart and respiratory disease mortality, respectively. Spline curves were quite linear over the PM concentrations seen on most days (dominated by combustion sources) in these cities, meanwhile on days with higher particulate levels (natural sources) a risk increase above certain PM levels was found, suggesting a curvilinear association and that, at least in some locations, PM(10-2.5) can play an important role in PM-related toxicity. The overall findings suggest that the establishment of new air quality standards for the short-term effect of PM(2.5) and PM(10-2.5) and further limiting levels of PM(10) in European Union is advisable.

Air pollution and mortality in the Canary Islands: a time-series analysis.

BACKGROUND: The island factor of the cities of Las Palmas de Gran Canaria and Santa Cruz de Tenerife, along with their proximity to Africa and their meteorology, create a particular setting that influences the air quality of these cities and provides researchers an opportunity to analyze the acute effects of air-pollutants on daily mortality. METHODS: From 2000 to 2004, the relationship between daily changes in PM10, PM2.5, SO2, NO2, CO, and ozone levels and daily total mortality and mortality due to respiratory and heart diseases were assessed using Generalized Additive Poisson models controlled for potential confounders. The lag effect (up to five days) as well as the concurrent and previous day averages and distributed lag models were all estimated. Single and two pollutant models were also constructed. RESULTS: Daily levels of PM10, PM2.5, NO2, and SO2 were found to be associated with an increase in respiratory mortality in Santa Cruz de Tenerife and with increased heart disease mortality in Las Palmas de Gran Canaria, thus indicating an association between daily ozone levels and mortality from heart diseases. The effects spread over five successive days. SO2 was the only air pollutant significantly related with total mortality (lag 0). CONCLUSIONS: There is a short-term association between current exposure levels to air pollution and mortality (total as well as that due specifically to heart and respiratory diseases) in both cities. Risk coefficients were higher for respiratory and cardiovascular mortality, showing a delayed effect over several days.

[Characterization of the atmospheric environment in Las Palmas de Gran Canaria and Santa Cruz de Tenerife, Spain: 2000-2004]. / Caracterización del ambiente atmosférico en Las Palmas de Gran Canaria y Santa Cruz de Tenerife: 2000 a 2004.

BACKGROUND: The island factor in the cities of Las Palmas de Gran Canaria and Santa Cruz de Tenerife, their meteorology and the proximity to the African Continent that originates the natural particulate matter transport over the islands, cause some specific features in their air quality. The aim of this paper is to characterize the air pollution from 2000 to 2004 as exposure indicator of both cities inhabitants. METHODS: 24 hour daily average variables of PM10, PM2,5, NO2, SO2 and O3 , 8 hours daily maxima moving averages of O3 y CO and 1 hour maxima of SO2, NO2, O3, CO, PM10 y PM2,5 were calculated. Daily levels of coarse particles were obtained subtracting PM2,5 from PM10. African dust events were identified. RESULTS: In Sta. Cruz de Tf daily means of SO2 (14.0 microg/m(3)N) and ozone levels (44.4 microg/m(3)N ) were higher than Las Palmas de GC levels (8.0 y 28.3 microg/m(3)N). Daily means of NO2 in Las Palmas de GC: 45.8 microg/m(3)N where higher than Sta. Cruz de Tf levels: 30.3 microg/m(3)N. Due to African dust outbreaks, some days in both cities exceeded 600 microg/m(3) of PM10 and 200 of PM2.5 24-h average. CONCLUSIONS: The air quality patterns were characterized by very high levels of African dust outbreaks that affect all PM size fractions. Different O3 seasonality exists respect European cities in addition to an urban-industrial ambient air in Sta. Cruz de TF and clearly urban in Las Palmas de GC. These results have to be considered in order to lay the foundations to suitable surveillance systems, analyse the potential impact on the Canary Islands citizens health and to get conclusions.

Caracterización del ambiente atmosférico en las Palmas de Gran Canaria y Santa Cruz de Tenerife. 2000 a 2004 / Characterization of the atmospheric environment in Las Palmas de Gran Canaria and Santa Cruz de Tenerife, Spain. 2000-2004

Fundamento: El carácter insular de las ciudades de Las Palmas de Gran Canaria y Santa Cruz de Tenerife, su meteorología y la proximidad del continente africano que favorece la llegada de material particulado de origen natural sobre las islas, determinan unas especificidades en su calidad del aire. El objetivo de este artículo es la caracterización de la contaminación atmosférica durante los años 2000 a 2004 como indicador de exposición de los habitantes de estas dos ciudades. Métodos: Se elaboraron los siguientes indicadores de contaminación: promedios de 24 horas de PM10, PM2,5, NO2, SO2 y O3; máximo de las 17 medias móviles octohorarias diarias de O3 y CO; máximo horario diario de SO2, NO2, O3, CO, PM10 y PM2,5. También se calcularon los niveles de la moda gruesa de partículas, como la diferencia entre los valores de PM10 y PM2,5 (PM10-2,5). Se identificaron episodios de intrusión africana. Resultados: En Sta Cruz de TF los promedios de SO2 (14µg/m3N) y de O3 (44,4 µg/m3N ) fueron superiores respecto a los de Las Palmas de GC (8 y 28,3 µg/m3N). Los promedios de NO2 en Las Palmas de GC: 45,8 µg/m3N fueron superiores a los de Sta. Cruz de TF: 30,3 µg/m3N. Debido a las intrusiones africanas, algunos días superaron los 600 µg/m3 de PM10 y los 200 de PM2.5 en ambas ciudades. Conclusiones: Se identifica un patrón de calidad del aire con episodios de polvo mineral africano que en superficie afecta a todas las fracciones granulométricas, una estacionalidad diferente a las ciudades europeas respecto al ozono, así como un patrón de contaminación urbano-industrial en Sta. Cruz de Tf y netamente urbano en Las Palmas de GC. Se hace necesario tener en cuenta estos resultados para analizar su posible impacto sobre la salud de los ciudadanos de las Islas Canarias y establecer sistemas adecuados de vigilancia (AU)

Background: The island factor in the cities of Las Palmas de Gran Canaria and Santa Cruz de Tenerife, their meteorology and the proximity to the African Continent that originates the natural particulate matter transport over the islands, cause some specific features in their air quality. The aim of this paper is to characterize the air pollution from 2000 to 2004 as exposure indicator of both cities´ inhabitants. Methods: 24 hour daily average variables of PM10, PM2,5, NO2, SO2 and O3 , 8 hours daily maxima moving averages of O3 y CO and 1 hour maxima of SO2, NO2, O3, CO, PM10 y PM2,5 were calculated. Daily levels of coarse particles were obtained subtracting PM2,5 from PM10. African dust events were identified. Results: In Sta. Cruz de Tf daily means of SO2 (14.0µg/m3N) and ozone levels (44.4 µg/m3N ) were higher than Las Palmas de GC levels (8.0 y 28.3 µg/m3N). Daily means of NO2 in Las Palmas de GC: 45.8 µg/m3N where higher than Sta. Cruz de Tf levels: 30.3 µg/m3N. Due to African dust outbreaks, some days in both cities exceeded 600 µg/m3 of PM10 and 200 of PM2.5 24-h average. Conclusions: The air quality patterns were characterized by very high levels of African dust outbreaks that affect all PM size fractions. Different O3 seasonality exists respect European cities in addition to an urban-industrial ambient air in Sta. Cruz de TF and clearly urban in Las Palmas de GC. These results have to be considered in order to lay the foundations to suitable surveillance systems, analyse the potential impact on the Canary Islands citizens health and to get conclusions (AU)

Encuesta de portadores de Neisseria Meningitidis en el area de salud de Gran Canaria (*) / Survey of N. Meningitidis carriers in the Gran Canary health jurisdiction

FUNDAMENTOS: Se plantea A) Conocer la tasa de portadores y los tipos circulantes de Neisseria Meningitidis en la población residente en el área de salud de Gran Canaria. B) Conocer el patrón de distribución de estos portadores. MÉTODOS: Se realizó un diseño descriptivo transversal, con un muestreo aleatorio en etapas múltiples y por conglomerados. Se determinó un tamaño muestral mínimo de 707 personas para una prevalencia esperada del 8,6 por ciento, con una confianza del 95,6 por ciento y precisión de 0,02. Asumiendo que un 15 por ciento de las personas no quisieran colaborar, se incrementó el tamaño muestral a 831 personas, distribuidas en cada conglomerado de manera proporcional a la población existente. Este tamaño se distribuyó a su vez, en cuatro grandes grupos de edad y sexo, proporcionalmente a su importancia en cada zona básica de salud seleccionada aleatoriamente. Los individuos de la muestra se identificaban entre los que acudían a las unidades de extracción, y una vez superados los criterios de exclusión se les solicitaba su colaboración voluntaria en el estudio. Si aceptaban, se les cumplimentaba un cuestionario que englobaba diferentes variables de interés epidemiológico y se les realizaba un frotis faríngeo. Al haber seleccionado los equipos de Atención Primaria con muestreo aleatorio simple y seguir el mismo método para elegir los individuos dentro de ellos, la estimación de la prevalencia se realizó mediante estimador no sesgado. RESULTADOS: Se obtuvieron un total de 828 muestras, lo que supuso un 99,6 por ciento de las previstas. Salvo tres, todos los individuos seleccionados participaron voluntariamente en el estudio, lo que le confiere una alta representatividad. Todas las cepas obtenidas correspondían a N. Meningitidis Serogrupo B, salvo una identificada como N. Meningitidis Serogrupo C Sero/Subtipo 4:P1.2,5. Las cepas de N. Meningitidis serogrupo B identificadas, correspondían a 25 serosubtipos diferentes. La prevalencia puntual tras haber estudiado la muestra fue de 6,45 por ciento, la varianza=0,0275 y el error estándar = 1,66. Podemos afirmar con una confianza del 95 por ciento, que la prevalencia de portadores de N. Meningitidis en el área de salud de Gran Canaria, se estima entre el 3,2 por ciento y el 9,7 por ciento. CONCLUSIONES: Se comprueba un claro predominio de cepas N. Meningitidis serogrupo B entre los portadores. No aparecen diferencias estadísticamente significativas en la prevalencia observada entre los distintos grupos de edad, ni entre ambos sexos (AU)