The outbreak of coronavirus disease 2019 (COVID-19), caused by the virus SARS-CoV-2, has been rapidly increasing in the United States. Boroughs of New York City, including Queens county, turn out to be the epicenters of this infection. According to the data provided by the New York State Department of Health, most of the cases of new COVID-19 infections in New York City have been found in the Queens county where 42,023 people have tested positive, and 3221 people have died as of 20 April 2020. Person-to-person transmission and travels were implicated in the initial spread of the outbreaks, but factors related to the late phase of rapidly spreading outbreaks in March and April are still uncertain. A few previous studies have explored the links between air pollution and COVID-19 infections, but more data is needed to understand the effects of short-term exposures of air pollutants and meteorological factors on the spread of COVID-19 infections, particularly in the U.S. disease epicenters. In this study, we have focused on ozone and PM_2.5, two major air pollutants in New York City, which were previously found to be associated with respiratory viral infections. The aim of our regression modeling was to explore the associations among ozone, PM_2.5, daily meteorological variables (wind speed, temperature, relative humidity, absolute humidity, cloud percentages, and precipitation levels), and COVID-19 confirmed new cases and new deaths in Queens county, New York during March and April 2020. The results from these analyses showed that daily average temperature, daily maximum eight-hour ozone concentration, average relative humidity, and cloud percentages were significantly and positively associated with new confirmed cases related to COVID-19; none of these variables showed significant associations with new deaths related to COVID-19. The findings indicate that short-term exposures to ozone and other meteorological factors can influence COVID-19 transmission and initiation of the disease, but disease aggravation and mortality depend on other factors.

Airborne dust and microorganisms are associated with respiratory diseases and increased mortality and morbidity. Farmers are at high risk of exposure to both of these hazards. Very limited information, however, is available on the combined exposures to both hazards on different types of farms. Moreover, most of the previous studies have measured the mass concentration of particles ignoring the particle size. In this study, farmers' exposure to airborne dust and microorganisms was studied using our newly developed personal sampling system. Particle number concentration and size distribution were measured with an optical particle counter. Simultaneously, particles were collected on a filter and analyzed for microorganisms. The field measurements were conducted in animal confinements (swine, poultry, and dairy) and during grain harvesting (corn and soybean). The results show the following average concentrations on the workers' breathing zone: 1.7 × 10 ⁶ to 2.9 × 10 ⁷ particles/m ³ for total dust, 0.9 × 10 ³ to 3.9 × 10 ⁴ spores/m ³ for total fungal spores, 0.3 × 10 ³ to 3.6 × 10 ⁴ CFU/m ³ for culturable fungal spores, 0.3 × 10 ⁴ to 3.3 × 10 ⁸ CFU/m ³ for culturable bacteria, and limit of detection (LOD) to 2.8 × 10 ³ CFU/m ³ for culturable actinomycetes in animal confinements. The respective concentrations were 4.4 × 10 ⁶ to 5.8 × 10 ⁷ particles/m ³ , 3.4 × 10 ⁴ to 6.1 × 10 ⁶ spores/m ³ , 8.2 × 10 ⁴ to 7.4 × 10 ⁶ CFU/m ³ , 0.4 × 10 ⁵ to 1.4 × 10 ⁶ CFU/m ³ , and LOD to 2.6 × 10 ⁴ CFU/m ³ during grain harvesting. The highest contribution of large particles (3–10 μ m) in total particles was found during grain harvesting, whereas the size distribution was dominated by smaller particles (< 3 μ m) in animal confinements. High fraction (up to 37%) of particles between 2–10 μ m was found to be fungal spores. The results indicate that an increase in the concentration of large dust particles (2–10 μ m) during grain harvesting was partially attributed to the increase in the concentration of the fungal spores. Overall, the combined exposure to airborne dust and microorganisms was found to be more severe during harvesting than in animal confinements.