Forecasting daily total pollen concentrations on a global scale.

BACKGROUND: There is evidence that global anthropogenic climate change may be impacting floral phenology and the temporal and spatial characteristics of aero-allergenic pollen. Given the extent of current and future climate uncertainty, there is a need to strengthen predictive pollen forecasts. METHODS: The study aims to use CatBoost (CB) and deep learning (DL) models for predicting the daily total pollen concentration up to 14 days in advance for 23 cities, covering all five continents. The model includes the projected environmental parameters, recent concentrations (1, 2 and 4 weeks), and the past environmental explanatory variables, and their future values. RESULTS: The best pollen forecasts include Mexico City (R2(DL_7) ≈ .7), and Santiago (R2(DL_7) ≈ .8) for the 7th forecast day, respectively; while the weakest pollen forecasts are made for Brisbane (R2(DL_7) ≈ .4) and Seoul (R2(DL_7) ≈ .1) for the 7th forecast day. The global order of the five most important environmental variables in determining the daily total pollen concentrations is, in decreasing order: the past daily total pollen concentration, future 2 m temperature, past 2 m temperature, past soil temperature in 28-100 cm depth, and past soil temperature in 0-7 cm depth. City-related clusters of the most similar distribution of feature importance values of the environmental variables only slightly change on consecutive forecast days for Caxias do Sul, Cape Town, Brisbane, and Mexico City, while they often change for Sydney, Santiago, and Busan. CONCLUSIONS: This new knowledge of the ecological relationships of the most remarkable variables importance for pollen forecast models according to clusters, cities and forecast days is important for developing and improving the accuracy of airborne pollen forecasts.

Fungal spores and pollen are correlated with meteorological variables: effects in human health at Hermosillo, Sonora, Mexico.

We conducted the first study of air pollen and fungal spores for Hermosillo, Sonora, where the human population is exposed to high temperatures and high levels of dust and suffers from diseases related to air quality. We sampled pollen and fungal spores daily in the air during 2016 using a volumetric spore trap Hirst-type sampler. We used simple linear correlation to investigate the association between pollen and spore counts and daily weather conditions. We found an Annual Pollen Integral of 16,243 pollen day/m3 and an Annual Spore Integral higher 222,365 spore day/m3. We identified 32 pollen taxa and 15 different spores. We found two periods of higher pollen and spore concentrations: March to May and August to October, the latter was the most severe. Spore and pollen concentrations in the air increased at higher temperature and higher relative humidity but decreased at higher precipitation. We detected negative impacts during summer and fall on population health, with 13,454 cases of people who presented diseases related to allergies. A peak in allergies is centered during October and correlates well with our peaks in pollen and spore concentrations; it seems that pollen of Poaceae is the one that generates most effects in allergic people.

Changes in Skin Test Aeroallergen Sensitization in Mexico Over the Past 14 Years and According to Climate.

Introduction: Aeroallergen exposure has an intra- and extra-domiciliary component and varies according to climatological zones. Mexico is a large country with a great variety of climates. A previous study (2009) evaluated skin prick test results (SPT) in different regions. In this study, we compare previous sensitization patterns from 14y ago with current ones and compare them between different climatological zones. Methods: Mexican allergists were asked to share their last 100 SPT results in patients with respiratory allergy. Clinics were grouped in (semi)humid vs (semi)dry zones. Results were analyzed nationwide and compared to the 2009 results, calculating odds ratio (OR) and 95% confidence intervals (95% CIs), with p <0.05 as cut-off. Similarly, we compared (semi)humid versus dry zones. Results: We collected 2915 SPT results from 28 clinics (19 cities). Dermatophagoides was the most frequently sensitizing allergen. There was a significant increase in SPT positivity from 2009 to 2023 in both in- and outdoor aeroallergens (OR 1.26-2.65, 95% CI from 1.06-1.50 to 1.99-3.52). Comparing dry-humid zones, sensitization to pollen from Oleaceae, Fagaceae (p < 0.0001 all) and most weeds is more frequent in humid zones, as are Dermatophagoides and cockroach (both p < 0.0001). Eucalyptus, mesquite, and all grass pollen sensitizations predominate in dry zones (p < 0.05-0.0001). There are no differences in sensitization to cat or dog between zones. Conclusion: We found a general increase in SPT sensitization over the past fourteen years, suggesting that this is probably not only due to climate change. The different sensitization profile throughout the country was mainly related to humidity. Repeating epidemiologic SPT studies over the years could help tracking changes in allergen sensitization over time.

Association of Allergic Sensitivity and Pollination in Allergic Respiratory Disease: The Role of Pollution.

Purpose: To evaluate the association between allergic sensitivity and pollen counts in patients with allergic respiratory disease (ARD) and its relationship with atmospheric pollutants. Methods: From 2012 to 2018, we evaluated the sensitivity by skin prick test in ARD patients. The pollen counts were analyzed according to international guidelines (2014-2018). The pollutant and meteorological data were obtained at the same time from AIRE-CDMX websites. We analyzed the association between allergic sensitivity and pollen counts using the χ2 test and stratified by disease allergic rhinitis (AR) and AR with asthma (ARwA), periods (before/after 2015), and pollination seasons (S1:2014-2015), (S2:2015-2016), (S3:2016-2017), (S4:2017-2018). Likewise, we correlated the pollen counts with the concentrations of pollutants using Pearson's correlation. For all analyses, we used SPSS v.21 software, and a p-value <0.05 was considered significant. Results: A total of 520 patients were enrolled, of whom 67.3% had ARwA and 33.7% had AR (p<0.05). The frequency of patients allergic to at least one pollen was higher compared with patients sensitive to indoor allergens (55.3% vs 44.6%, p<0.001). A total of 46.8% of the patients were only sensitive to trees in comparison to other outdoor allergens (p<0.001). The Fraxinus sp. and the Cupressaceae family allergens were approximately two times more frequent than the other tree allergens in both diseases (p<0.05). These pollens doubled their counts since 2015 (p<0.001), which was associated with increases in sensitivity for Fraxinus sp. and the Cupressaceae family compared to previous years (p<0.001). Regarding pollutants, the most significant correlations were with PM10, NO2, PMCO for Fraxinus sp. pollen concentrations in all seasons (p≤0.02). Conclusion: The high increases in pollen counts of the Fraxinus sp. and Cupressaceae family were associated with increases in the frequency of sensitization to these species, and this phenomenon correlated with increases in PM10, NO2, and PMCO.

Aerobiological study of bacterial and fungal community composition in the atmosphere of Mexico City throughout an annual cycle.

The atmosphere as a temporary habitat for airborne microbial communities is a valuable topic to explore, and it is through aerobiological studies that the diversity of biological particles and their release, emission, transport, deposition, and impact are assessed. Specific microorganisms are involved in meteorological processes, and phytosanitary and public health concerns. Airborne microbial composition is related to factors such as geographic region and weather conditions. In this study a metagenomic approach was used to determine the composition of bacterial and fungal communities in the air of two different land-use areas (urban area and semi-rural area), during dry and rainy seasons in Mexico City. Air sampling was carried out with a Hirst-type spore trap, collecting the samples simultaneously in both study areas. Forty-two bioaerosol samples were collected, and the DNA obtained was sequenced using Next-Generation Sequencing. The results indicated that the bacterial communities were represented mainly by the phyla Actinobacteria, Proteobacteria, Firmicutes, Bacteroidetes, Cyanobacteria, and the fungal communities by the phyla Ascomycota followed by Basidiomycota. The evident changes in microbial composition were related more to seasonality than to locality, since both UA and SRA showed a high degree of urbanization, despite some differences in land use. Continuous monitoring of atmospheric bioaerosols is essential to determine the influence of meteorological factors on the composition of the aerial microbiota.

Fungal diversity and Aspergillus species in hospital environments.

INTRODUCTION AND OBJECTIVE: Nosocomial invasive fungal infections, particularly aspergillosis, are an increasing problem in immunocompromised patients. The presented study evaluates fungal diversity and the presence of Aspergillus in air samples from two hospitals. MATERIALS AND METHODS: Over the course of one year (rainy and dry seasons), the air was sampled from three areas in two hospitals (1 and 2) using a single-stage Andersen viable particle sampler (Thermo Scientific, Waltham, MA, USA). The fungi were identified by macro- and micromorphology, and the number of colony forming units (CFU)/m(3) air and their richness, abundance, and diversity were determined. Isolates Aspergillus genus were characterized by their thermotolerance. RESULTS: The CFU/m(3) air was similar at both hospitals during the two seasons, but different between the sampled areas. Results showed 10 fungal genera for hospital 1, and 8 for hospital 2. The most abundant were Penicillium, Cladosporium and Aspergillus. The thermotolerance test confirmed the identification of A. fumigatus section Fumigati. The highest growth rate was found in Aspergillus section Nigri. CONCLUSION: Determining the fungal diversity in the two hospitals was important because all the species have the potential to be pathogenic, especially the section Fumigati.

Evaluation of genotoxic and cytotoxic effects in human peripheral blood lymphocytes exposed in vitro to neonicotinoid insecticides news.

Calypso (thiacloprid), Poncho (clothianidin), Gaucho (imidacloprid), and Jade (imidacloprid) are commercial neonicotinoid insecticides, a new class of agrochemicals in México. However, genotoxic and cytotoxic studies have not been performed. In the present study, human peripheral blood lymphocytes (PBL) were exposed in vitro to different concentrations of the four insecticides. The genotoxic and cytotoxic effects were evaluated using the alkaline comet and trypan blue dye exclusion assays. DNA damage was evaluated using two genotoxicity parameters: tail length and comet frequency. Exposure to 9.5 × 10(-6) to 5.7 × 10(-5) M Jade; 2.8 × 10(-4) to 1.7 × 10(-3) M Gaucho; 0.6 × 10(-1) to 1.4 × 10(-1) M Calypso; 1.2 × 10(-1) to 9.5 × 10(-1) M Poncho for 2 h induced a significant increase DNA damage with a concentration-dependent relationship. Jade was the most genotoxic of the four insecticides studied. Cytotoxicity was observed in cells exposed to 18 × 10(-3) M Jade, 2.0 × 10(-3) M Gaucho, 2.0 × 10(-1) M Calypso, 1.07 M Poncho, and cell death occurred at 30 × 10(-3) M Jade, 3.3 × 10(-3) M Gaucho, 2.8 × 10(-1) M Calypso, and 1.42 M Poncho. This study provides the first report of genotoxic and cytotoxic effects in PBL following in vitro exposure to commercial neonicotinoid insecticides.