Aerobiologia最新文献

Airborne fungal spores of the genus Alternaria pose challenges for accurate airborne spore identification by automatic bioaerosol monitors, because of their significant implications for public health and agriculture due to their role as airborne allergen and plant pathogen. These systems require high-quality reference data for training algorithms by machine learning. Alternaria alternata was cultured on three different media, including exposure to UV light to favor sporulation. Spore morphology was evaluated both macroscopically and microscopically, and chemical analysis was conducted using micro-Raman spectroscopy to assess spore composition. Significant differences were observed in colony morphology and spore characteristics among culture media. While typical spores predominated, atypical forms were also identified, which may represent a potential bias for identification. Comparative analysis with air samples by the Hirst method also revealed overall differences in spore morphology pattern. Standardizing culture conditions and accounting for variability in spore properties are essential for improving the reliability of bioaerosol monitoring systems. Further research is needed to refine detection methods for A. alternata and other airborne fungal spores.

Accurate identification and quantification of pollens (e.g., pollen of a flower, airborne pollens) is essential to understand plant pollination and reproductive biology, pollen aerobiology, and plant–insect interactions. Currently, a couple of methods are available for pollen counting, such as manual counting, flow cytometry-based and image software-based counting. However, due to inconsistent results and experimental repeatability, a more accurate, consistent, and high-throughput quantification approach is required. This study evaluated and compared the performance between a proposed Swin-transformer-YOLOv5 (S-T-YOLOv5) and common YOLO models in pollen detection and quantification. The present study demonstrated that the S-T-YOLOv5 outperformed other YOLO models, including YOLOv3, YOLOv4, YOLOR, and YOLOv5 for alfalfa (Medicago sativa L.) pollen detection and quantification, with excellent precision (99.6%), recall (99.4%), F₁-score (0.995), mAP50 (99.4%), and mAP50-95 (76.2%) values. The mAP50-95 (mAP at an IoU of 0.5–0.95) of S-T-YOLOv5 was 9.9, 58.7, 25.3 and 8.2% higher than those of YOLOv3, YOLOv4, YOLOR, and YOLOv5, respectively. Additionally, the S-T-YOLOv5 showed a good transferability in quantifying pollen with varied sizes and shapes in different plant species, including annual fleabane, camelina, Canadian goldenrod, Indian lettuce, mustard, and oilseed rape. In summary, our results showed that the S-T-YOLOv5 is an accurate, robust, and widely adaptable pollen quantification approach, with minimizing errors and labor expense. We would like to highlight the potential application of S-T-YOLOv5 in quantifying samples of airborne pollens from a known pollen source or insect-dispersed pollens (e.g., alfalfa) in supporting the environmental risk assessment of genetically engineered (GE) plants.

Grass pollen is the most common cause of pollen allergies in Europe. However, growing evidence suggests that air pollution and climate change may contribute to the rising number of allergic cases and worsening symptoms. This narrative review article aims to summarize the impacts of increased health complications based on pollution research in recent years, obtained from ecological, molecular and clinical studies to provide a new perspective on the impact of pollutants on the environment and human health. Our detailed literature review includes studies on pollution and its effect on pollen allergens, which cause allergy symptoms, but only in the case of three grass species: Dactylis glomerata, Lolium perenne and Phleum pratense.

The airborne fungal spore content of the Havana city was studied from January to December 2017 by means a Hirst type volumetric methodology. Ten spore types were recorded for the first time in the atmosphere of the Cuba Island. A morphobiometrical description of the characteristics of each kind of spore was conducted. Four ascomycetes were identified (Amphisphaeria, Ascobolus, Cucurbidothis-type and Lewia) and six conidial genera were identified (Exosporium, Helicomina, Microsporum, Solheimia, and Trichocladium). Most of them are pantropical, saprophytes of different plants, and they could cause allergies or diseases in fruit crops of urban agriculture. This work increases the knowledge about the diversity of the airborne fungi in a neotropical region.

Bioaerosols are useful indicators of plant phenology and can demonstrate the impacts of climate change on both local and regional scales (e.g. pollen monitoring/flowering phenology). Analysing bioaerosols with eDNA approaches are becoming more popular to quantify the diversity of airborne plant environmental DNA (eDNA) and flowering season of plants and trees. Leaf abscission from broadleaved trees and other perennial species can also indicate the status of plant health in response to climate. This happens primarily during autumn in response to seasonal growth conditions and environmental factors, such as changing photoperiod and reduced temperatures. During this period biological material is released in larger quantities to the environment. Here, rural bioaerosol composition during late summer and autumn was captured by MiSEQ sequencing of the rRNA internal transcribed spacer 2 (ITS2) region, a common marker for taxonomic variation. Meteorological parameters were recorded from a proximal weather station. The composition of atmospheric taxa demonstrated that deciduous tree DNA forms part of the bioaerosol community during autumn and, for several common broadleaved tree species, atmospheric DNA abundance correlated to high wind events. This suggests that both flowering and autumn storms cause bioaerosols from deciduous trees that can be detected with eDNA approaches. This is an aspect that must be considered when eDNA methods are used to analyse either pollen or other fragments from trees.

Atopic dermatitis (AD) is a highly prevalent and multifactorial condition influenced by environmental factors such as the concentration of airborne allergens and meteorological variables. However, there is a lack of consensus on the role of these factors in triggering AD, particularly in tropical areas, where high values of these variables are common and studies are scarce. Therefore, this ecological study aimed to assess the association between concentrations of outdoor fungal spores and tree pollen, temperature, and water vapor pressure with AD-related medical services utilization in children 12 years or younger residing in a tropical urban area (San Juan, Puerto Rico), from 2017 to 2020. The study analyzed medical records of two dermatology clinics and local data on outdoor aeroallergens and meteorological variables to determine the number of AD-related medical claims during the study period, based on their medical diagnostic code. The multivariate regression analysis showed that high tree pollen concentrations (IRR = 1.2670, p = 0.032) and low average temperatures (IRR = 1.3114, p = 0.009) increased the probability of AD-related medical claims. In contrast, this probability was reduced with high average temperatures (IRR = 0.6782, p = 0.001) and low water vapor pressure values (IRR = 0.7802, p = 0.022). No associations were found with outdoor fungal spores. In conclusion, this study found that high tree pollen concentrations and low temperatures increased the utilization of AD-related medical services. Educating individuals about reducing exposure to unfavorable environmental conditions could be a useful intervention in preventing the exacerbation of AD.

Bioaerosols can be spread through coughing, sneezing, respiratory droplets and aerosol particles, and public awareness of the health risks of bioaerosols has increased. Based on bioaerosol culturable microbe concentration data collected from March–December in 2015, 2018 and 2019, the health risks of bioaerosols were assessed by air quality level, month, population, and particle size using an average daily dose rate model. The concentration of culturable microorganisms is related to the air quality index (AQI). Under AQI values ranging from 51–100, the concentration of culturable microorganisms was the highest, while the concentration of culturable microorganisms was the lowest for AQI values ranging from 101–150. The health risk in June and July 2015 was the highest, the change trends in 2018 and 2019 were similar, the health risk was the highest in October, and the health risk of bioaerosols along the inhalation route was 10³–10⁴ times that along the exposure route. The health risk of bioaerosols was generally higher in summer and autumn than in spring and winter over the three-year period. The health risk for different categories of individuals indicated the same trend over the 3-year period, with the health risk for adults exceeding that for children and the health risk for men exceeding that for women. The health risk of bioaerosols was high under particle sizes ranging from 1.10–4.70 μm. The study results could provide data support for the analysis of bioaerosol-related health risks and offer a reference for the prevention and control of urban microbial diseases.

Airborne pathogens pose a great threat to public health, and their appearance in bioaerosol also increases the contiguousness due to the long survival time and transmitting range. Real-time monitoring and rapid detection methods provide more effective prevention and control of airborne pathogens. The whole procedure could be divided into bioaerosol collection and detection processes. This review presents the basic principles and recent advances in commonly used methods for each of these two steps. We categorized four different kinds of collection methods based on their principles and discussed possible enrichment methods against a small amount of targets. Four different detection methods were compared regarding their ability to perform rapid testing. In the final section, we analyzed the latest trend in combining all these steps to set up a single device or platform for rapid, automated, and continuous on-site bioaerosol monitoring to overcome time and space constraints and increase the speed of the entire monitoring process. We conclude that an integrated all-in-one system using a microfluidic platform is the most promising solution for real-time monitoring of airborne pathogens, since they are capable of simplifying operational steps, efficient collection, and high-throughput detection, demonstrating the strong potential of field-deployable platforms.

Graphical abstract

Bioaerosols are particles of great importance for several fields of research, and spores produced by fungi can exist as bioaerosols when suspended in the air. Microbiological standards for environmental monitoring of outdoor air parameters can be achieved by analyzing the relationship between airborne microorganisms and the prevailing environmental conditions. The outdoor air of the Metropolitan Region of São Paulo and the rural area in a city of the state of São Paulo (Ibiúna/SP), both in Brazil, were evaluated for the presence of microorganisms using the MAS-100 ECO (Merck®, Fr.) and M Air T (Millipore®) air sample collectors. Dichloran Rose-Bengal Chloramphenicol and Tryptic Soy Agars were used for fungal and bacterial isolation, respectively. Bacterial colonies were counted, and the plates with fungal colonies were sent for phenotypic identification up to genus and species level, respectively. Data on pollutant concentrations were obtained from the Environmental Company of the State of São Paulo. The highest number of Colony-Forming Units/m³ (CFU/m³) of microorganisms was measured in the winter and summer seasons, respectively, but the greatest Spore-Forming Units (SFU) of fungi were found in the rural area, where pollutant concentrations were lower. Nitrogen dioxide (NO₂) had a slightly positive influence on the concentration of SFU of fungi in both areas studied. Sulfur dioxide (SO₂) pollutant concentrations had both positive and negative great relations showing influence on microbial counts in the air of the rural area. In the rural area, the low bacteria count was influenced negatively by the low concentration of carbon monoxide (CO). The microbial counts were related to each other, as well as to the concentrations of pollutants, shown by all the correlations seen, indicating microorganisms as biomarkers of pollution in outdoor areas. The influence of environmental factors on the population and outdoor air biome is also explicit.

Pollen, particularly from the Ambrosia genus, plays a pivotal role in triggering allergic rhinoconjunctivitis symptoms. This review delves into the global background of Ambrosia, focusing on its origins, invasive potential, and spread to South America. The ecological niche for Ambrosia species is explored, emphasizing its stability globally but exhibiting unique and dynamic features in South America. Information on Ambrosia pollen concentration in South America is summarized, revealing varying levels across countries. The establishment of new aerobiology stations, as highlighted in the latest findings, contributes valuable data for understanding allergen risk management in the region. The health perspective addresses the rise in allergic diseases due to climate change, emphasizing the need for continuous monitoring, especially in South America. Agricultural damage inflicted by Ambrosia is discussed, emphasizing its invasive potential, high seed production, and negative impact on crops, forage quality, and livestock. The review also positions Ambrosia as a marker of climate change, discussing the effects of global warming on pollen seasons, concentrations, and allergenic characteristics. The importance of expanding aerobiology stations in South America is underscored, requiring collaborative efforts from government, scientific societies, and academic institutions. The review concludes by advocating for increased monitoring to address potential challenges posed by Ambrosia, offering a basis for tailored interventions and future research in South American regions.