Diversity of Bioaerosols in Selected Rooms of Two Schools and Antibiotic Resistance of Isolated Staphylococcal Strains (Bydgoszcz, Poland): A Case Study

Abstract

The present study is aimed at evaluating microbiological air pollution in libraries, cafeterias and selected classrooms of two schools in Bydgoszcz city, northern Poland and determining the antibiotic resistance of Staphylococcal strains isolated from the indoor air. One of the investigated schools (School A) is located in the very center of the city, in the vicinity of a park, among old houses and stone-lined streets, while the other (School B), among modern residential buildings, close to a street with heavy traffic. In each school, air samples were collected in the morning, always from all three sampling sites, using the MAS-100 sampler. Selective growth media were used for bacteria and mold isolation and quantifying analysis. The antibiotic resistance of the isolated mannitol-positive staphylococci was assessed using the disc diffusion method in accordance with EUCAST recommendations. The highest mean concentration of heterotrophic bacteria was recorded in the cafeterias: 884 CFU m−3 in School A and 1906 CFU m−3 in School B. Molds were the most abundant in the library and cafeteria in School B, where their average concentration exceeded 300 CFU m−3. Cladosporium and Penicillium species prevailed, while Fusarium, Acremonium and Aspergillus were less abundant. Airborne mannitol-positive staphylococci were recorded at low concentrations, ranging from 6 to 11 CFU m−3 on average. According to the taxonomic analysis, Staphylococcus aureus isolates were the most abundant in both schools, followed by S. xylosus, S. haemolyticus and S. saprophyticus. The antibiograms indicated that resistance to erythromycin was common in 62.5% of the isolated staphylococcal strains. Levofloxacin and gentamicin were the most effective antibiotics. No multidrug-resistant strains were identified.

Overview of fungal isolates on heritage collections of photographic materials and their biological potency

“…9 Future perspectives Some of the work that could improve in the future is to standardise the sampling procedures, especially air sampling procedures as, there are no widely accepted methodologies for its measurement. Therefore, there is a need to investigate the potential of passive (based on spore sedimentation; expressed in CFU/m 2 /h) and active (based on vacuum pumps sucking air; expressed in CFU/m 3 ) air sampling strategies to explain visible mold, and understand how room characteristics of a museum or a film archive correlate with the obtained readings [161][162][163][164][165].…”

The Well-Being of Children in Nurseries Does Not Have to Be Expensive: The Real Costs of Maintaining Low Carbon Dioxide Concentrations in Nurseries

“…The analyses showed the degree of air quality improvement (smaller CO 2 concentration) depended on the cubic area of the room. Małecka-Adamowicz et al [64] concluded the same thing regarding bio-aerosols. Larger per child cubic areas led to slower CO 2 concentration increases.…”

“…Filters applied in ventilation units are limited to pollution existing in the external environment (dusts, PM 10 , PM 5 , PM 2.5 ). Air quality improvement due to dust control should also improve the micro-biological situation of air, because dusts carry bacteria and fungi, including pathogens as noted by Małecka-Adamowicz et al [64]. It is also worth noting the suggestions of Bryzel et al [6] that air purification in the room is ineffective and should be purified before being delivered inside.…”

Staphylococci and fecal bacteria as bioaerosol components in animal housing facilities in the Zoological Garden in Chorzów

“…The presence of staphylococci indicates the possible inherence of pathogenic microorganisms, in which antibiotic resistance has been observed with increasing frequency over the past several decades (Małecka-Adamowicz et al 2020 ). In this study Staphylococcus succinus was the most numerous staphylococcal species (approx.…”