Microbiological Contamination Assessment in Higher Education Institutes

Viegas, Carla Pimenta Raquel Dias Marta Gomes Bianca Brito Miguel Aranha Caetano Liliana Carolino Elisabete Gomes Anita Quintal

The higher education sector represents a unique environment and it acts as a work environment, a learning environment for students, and frequently, also a home environment. The aim of this study was to determine the microbial contamination (SARS-CoV-2, fungi, and bacteria) in Higher Education Facilities (HEI) by using active and passive sampling methods and combining culture-based methods with molecular tools targeting Aspergillus section Fumigati. In addition, the resistance to azole profile was also assessed. Surface samples showed a range of total bacterial contamination between 1 × 103 to 3.1 × 106 CFU·m−2, while Gram-negative bacteria ranged from 0 to 1.9 × 104 CFU·m−2. Fungal contamination ranged from 2 × 103 to 1.8 × 105 CFU·m−2 on MEA, and from 5 × 103 to 1.7 × 105 CFU·m−2 on DG18. The most prevalent species found on both media was Cladosporium sp. (47.36% MEA;32.33% DG18). Aspergillus genera was observed on MEA (3.21%) and DG18 (14.66%), but not in the supplemented media used for the azole screening. Aspergillus section Fumigati was detected in 2 air samples (2.22%, 2 out of 90 samples) by qPCR. When testing for SARS-CoV-2 all results were negative. The present study showed that although cleaning and disinfection procedures are done regularly due to the COVID-19 pandemic, being effective in eliminating SARS-CoV-2, surfaces were often contaminated with microorganisms other than SARS-CoV-2. This can be a result of increasing resistance to biocides, and to the wide range of environmental factors that can contribute to the dissemination of microbial contamination indoors. [ABSTRACT FROM AUTHOR] Copyright of Atmosphere is the property of MDPI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)