Airborne pollen calendar of Lublin, Poland.
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Pollen concentration in the atmosphere of Lublin (eastern Poland) was studied by means of volumetric method using Hirst sampler (VPPS 2000, Lanzoni) in 2001-2002. The pollen trap was mounted at the height of 15 m in the centre of Lublin. On the basis of analysis of mean daily values of pollen concentration, the pollen calendar was constructed for 16 taxa producing the allergenic pollen: Alnus, Corylus, Populus, Ulmus, Fraxinus, Betula, Carpinus, Quercus, Fagus, Pinaceae, Poaceae, Rumex, Plantago, Chenopodiaceae, Artemisia, Urticaceae. Great differences referring to the course of pollen seasons for most of the studied taxa of trees within the 2 years of study were found. They were associated with the beginning and end of the pollen season, the amount and the date of maximum pollen concentration occurrence, as well as annual sums of pollen grains. Much lower differentiation was observed in the case of herbaceous plants. This referred mainly to maximum concentration occurrence dates (Urtica, Poaceae) and the length of pollen season (Chenopodiaceae). The most similar course of pollen seasons during 2 years was recorded for Artemisia. Among trees, the highest pollen concentrations were recorded for Betula, Pinaceae and Alnus; the lowest for Ulmus, Fagus and Corylus. Very high concentration of herbaceous plant's pollen was observed for Poaceae and Urtica; Plantago and Chenopodiaceae showed the lowest level. Annual sums of pollen grains for Alnus, Populus, Quercus, Betula and Pinaceae were much higher in 2001, but in the case of Ulmus, Fraxinus, Carpinus, Fagus the annual sums of pollen grains in 2002 were almost twice as high as in 2001. For 5 among 7 herbaceous taxa, annual sums of pollen grains in both years were similar. (+info)
Malaria epidemic early warning and detection in African highlands.
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Malaria epidemics have long been known to recur in the African highlands. Efforts to develop systems of early warning and detection for epidemics are outlined here with special emphasis on the Highland Malaria Project (HIMAL). This project has been conducting research on the operational implementation of a district-based surveillance and epidemic-monitoring system using a network of sentinel sites in four pilot districts of Kenya and Uganda. The potential use of weather monitoring as well as disease surveillance for effective early warning is being investigated. (+info)
Ambient pollution and blood pressure in cardiac rehabilitation patients.
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BACKGROUND: Multiple studies have demonstrated a consistent association between ambient particulate air pollution and increased risk of hospital admissions and deaths for cardiovascular causes. We investigated the associations between fine particulate pollution (PM2.5) and blood pressure during 631 repeated visits for cardiac rehabilitation in 62 Boston residents with cardiovascular disease. METHODS AND RESULTS: Blood pressure, cardiac risk factor, and exercise data were abstracted from records of rehabilitation visits between 1999 and 2001. We applied mixed-effect models, controlling for body mass index, age, gender, number of visits, hour of day, and weather variables. For an increase from the 10th to the 90th percentile in mean PM2.5 level during the 5 days before the visit (10.5 microg/m3), there was a 2.8-mm Hg (95% CI, 0.1 to 5.5) increase in resting systolic, a 2.7-mm Hg (95% CI, 1.2 to 4.3) increase in resting diastolic, and a 2.7-mm Hg (95% CI, 1.0 to 4.5) increase in resting mean arterial blood pressure. The mean PM2.5 level during the 2 preceding days (13.9 microg/m3) was associated with a 7.0-mm Hg (95% CI, 2.3 to 12.1) increase in diastolic and a 4.7-mm Hg (95% CI, 0.5 to 9.1) increase in mean arterial blood pressure during exercise in persons with resting heart rate > or =70 bpm, but it was not associated with an increase in blood pressure during exercise in persons with heart rate <70 bpm. CONCLUSIONS: In patients with preexisting cardiac disease, particle pollution may contribute to increased risk of cardiac morbidity and mortality through short-term increases in systemic arterial vascular narrowing, as manifested by increased peripheral blood pressure. (+info)
Allergenic airborne grass pollen in Szczecin, Poland.
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Grass pollens are known as very potent aeroallergens. The aim of the study was to analyse the grass pollen season in Szczecin (western Poland) in the years 2000-2003 and to establish a relationship between the meteorological conditions and the pollen counts of Poaceae. The meteorological parameters analysed were the maximum and mean air temperature, relative humidity, amount of precipitation and wind speed. Measurements were performed mainly by the volumetric method. In parallel, gravimetric monitoring was conducted in 4 Szczecin city districts in order to establish the spatial distribution of pollen in aeroplankton. Pollen seasons were defined as the periods in which 95 % of the total catch occurred. In the 4 years studied, the lowest concentration of grass pollen was observed in 2000 with the maximum value of 123 pollen grains in 1 m3 per 24 h. In subsequent seasons, the concentration of Poaceae pollen increased and the highest concentration of grass pollen, equal to 809 pollen grains in 1 m3 per 24 h was noted in 2003. The majority of Poaceae species have constant periods of pollen release and the high number of their species means that the pollen season is long and lasts from the beginning of May until the middle of September. The longest pollen season was observed in the year 2000 when the lowest pollen count was found. In sensitive persons the symptoms of pollinosis occur after some threshold pollen count value, which for grass is 30 grains in 1 m3 per 24 h. Therefore, the greatest threat from Poaceae pollen allergens is noted from the middle of May and until the end of July, and at the beginning of September. Analysis of the pollen distribution in different Szczecin city districts determined by the gravimetric method, has shown that the highest exposure to grass pollen allergens occurs in the districts Zelechowa and Srodmiescie, in the area with parks, villas and gardens or garden allotments. However, in the pollen season the threshold Poaceae pollen count value is usually exceeded in the entire city. Statistically significant correlations have been found between the grass pollen count in the air and the maximum wind speed, air temperature, amount of precipitation and relative air humidity. The pollen count of grass is determined by the diversity of local flora and weather conditions, especially by the air temperature and relative humidity. (+info)
Quantitative trends in airborne loads of Celtis sinensis pollen and associations with meteorological variables in a subtropical Australian environment.
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Celtis sinensis is an introduced plant species to the southeastern region of Queensland that has had a destructive affect on indigenous plant communities and its pollen has been identified as an allergen source. Pollen belonging to C. sinensis was sampled during a 5-year (June 1994-May 1999) atmospheric pollen-monitoring programme in Brisbane, Australia, using a Burkard 7-day spore trap. The seasonal incidence of airborne C. sinensis pollen (CsP) in Brisbane occurred over a brief period each year during spring (August-September), while peak concentrations were restricted to the beginning of September. Individual CsP seasons were heterogeneous with daily counts within the range 1-10 grains m(-3) on no more than 60 sampling days; however, smaller airborne concentrations of CsP were recorded out of each season. Correlation co-efficients were significant each year for temperature (p < 0.05), but were less consistent for precipitation (p > 0.05) and relative humidity (p > 0.05). A significant relationship (r2 =0.81, p=0.036) was established between the total CsP count and pre-seasonal average maximum temperature; however, periods of precipitation (> 2 mm) were demonstrated to significantly lower the daily concentrations of CsP from the atmosphere. Given the environmental and clinical significance of CsP and its prevalence in the atmosphere of Brisbane, a clinical population-based study is required to further understand the pollen's importance as a seasonal sensitizing source in this region. (+info)
Atmospheric concentrations of Cladosporium spp. and Alternaria spp. spores in Zagreb (Croatia) and effects of some meteorological factors.
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The aim of the study was to analyse the relationship between meteorological conditions and Alternaria and Cladosporium spore concentrations in the air of Zagreb in August 2002 and August 2003. These months were chosen because they represented climatic extremes. A 7-day VPPS 2000 Hirst volumetric pollen and spore trap was used for spore sampling. Spores marked as 'others' (ascospores, basidiospores, Epicoccum, Ustilago, Pithomyces, Helminthosporium, Stemphylium, Torula, Botrytis, Didymella) were found to have predominated in the month of August in both 2002 and 2003 with 91.1% and 70.5%, respectively. Because of favourable weather conditions (higher air temperature and minimal precipitation) in August 2003, the concentrations of Alternaria and Cladosporium spores were 3.4-fold those recorded in the same month in 2002. Also, the peak daily concentrations of these spores were measured on days without precipitation and with higher air temperature. Intradiuranal variation in the Alternaria and Cladosporium spore concentrations was identical in 2002 and 2003 (lowest in 2-hour interval between 06:00-08:00, and highest between 10:00-12:00). In spite of the three-fold increase in the Cladosporium spore concentration in August 2003, the borderline concentration of 3,000 spores/m3 air that is associated with the occurrence of allergic reactions was only exceeded on a single day. Air concentration of Alternaria spores exceeded borderline value of 100 spores/m3 air on as many as 17 days, suggesting that at that time of the year the risk of allergic reaction was only present in individuals allergic to this spore type. (+info)
An initial investigation of the association between the SARS outbreak and weather: with the view of the environmental temperature and its variation.
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OBJECTIVE: To understand the association between the SARS outbreak and the environmental temperature, and to provide a scientific basis for prevention and control measures against it. METHODS: The daily numbers of the probable SARS patients and the daily meteorological factors during the SARS outbreak period in Hong Kong, Guangzhou, Beijing, and Taiyuan were used in the data analysis. Ecological analysis was conducted to explore the association between the daily numbers of probable SARS patients and the environmental temperature and its variations. RESULTS: There was a significant correlation between the SARS cases and the environmental temperature seven days before the onset and the seven day time lag corresponds well with the known incubation period for SARS. The optimum environmental temperature associated with the SARS cases was between 16 degrees C to 28 degrees C, which may encourage virus growth. A sharp rise or decrease in the environmental temperature related to the cold spell led to an increase of the SARS cases because of the possible influence of the weather on the human immune system. This study provided some evidence that there is a higher possibility for SARS to reoccur in spring than that in autumn and winter. CONCLUSION: Current knowledge based on case studies of the SARS outbreak in the four cities suggested that the SARS outbreaks were significantly associated with the temperature and its variations. However, because the fallacy and the uncontrolled confounding effects might have biased the results, the possibility of other meteorological factors having an affect on the SARS outbreaks deserves further investigation. (+info)
Variation in ragweed (Ambrosia artemisiifolia L.) pollen concentration in central Croatia, 2002-2003.
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The aim of the study was to determine the onset, duration and termination of the ragweed pollen season; intradiurnal, daily and monthly pollen variation, and possible differences in the occurrence and concentration of ragweed pollen according to sampling sites between 2002 and 2003. The study was conducted at three sampling sites in central Croatia over two pollen seasons (2002 and 2003) using the volumetric method of sampling (Hirst type sampler). In 2003, the ragweed pollen season was by 43 % longer and the percentage proportion of ragweed pollen by 3.4 % greater in comparison with 2002. The total ragweed pollen count and number of days with ragweed pollen concentration greater than 30 pollen grains per m (3) air showed a declining tendency from East to West in both seasons. The intradiurnal peak concentration occurred between 10.00-14.00. The air concentration of ragweed pollen decreased with temperature decline and precipitation. Results of the study provided useful information to individuals allergic to ragweed pollen thereby allowing them to adjust their outdoor activities to avoid contact with the allergen. (+info)