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Isolation of Cryptococcus species from the external environments of hospital and academic areas
Murilo de Oliveira Brito1, Meliza Arantes de Souza Bessa2, Ralciane de Paula Menezes3
1Faculty of Medicine, Federal University of Uberlandia, Uberlandia, Minas Gerais, Brazil. britomurilo51@gmail.com.
Introduction:
Fungi of the genus Cryptococcus are cosmopolitan and may be agents of opportunistic mycoses in immunocompromised and sometimes immunocompetent individuals. Cryptococcus species are frequently isolated from trees and bird excreta in the environment and infection occurs by inhalation of propagules dispersed in the air. The aim was to investigate Cryptococcus species in bird excreta and tree hollows located in a university hospital area and in an academic area of a university campus.
Methodology:
A total of 40 samples of bird excreta and 41 samples of tree hollows were collected. The identification of the isolates was done by classical methodology and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.
Results:
Twenty (62.5%) isolates of Cryptococcus were found in bird excreta and 12 (37.5%) in tree hollows. C. laurentii (currently Papiliotrema laurentii) was the most frequent species in both samples, being found in 5 samples of excreta and in 8 tree hollows. The diversity of species found in excreta (C. laurentii, C. albidus [currently Naganishia albida], C. liquefaciens [currently N. liquefaciens], C. friedmanii [currently N. friedmannii] and others) was higher than in tree hollows (C. laurentii, C. flavescens [currently Papiliotrema flavescens], and other yeasts).
Conclusion:
Many Cryptococcus species were isolated from excreta and tree hollows, and this fact is important for understanding the environmental epidemiology of those emerging pathogens for public health, as a way to implement surveillance actions and control of cryptococcosis.
Insights
Cryptococcus fungi were identified in bird excreta and tree hollows on a university campus. Papiliotrema laurentii was the most common species, highlighting environmental surveillance needs for cryptococcosis control.
Area of Science:
- Environmental microbiology
- Medical mycology
- Public health
Background:
- Fungi of the genus Cryptococcus are widespread environmental organisms.
- These fungi can cause opportunistic mycoses in susceptible individuals.
- Infection typically occurs through inhalation of airborne fungal propagules.
Purpose of the Study:
- To investigate the presence and diversity of Cryptococcus species.
- Samples were collected from bird excreta and tree hollows.
- Study sites included a university hospital and an academic campus area.
Main Methods:
- Collected 40 bird excreta samples and 41 tree hollow samples.
- Utilized classical mycological identification methods.
- Employed matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) for precise identification.
Main Results:
- Isolated Cryptococcus from 20 bird excreta (62.5%) and 12 tree hollow (37.5%) samples.
- Papiliotrema laurentii (formerly C. laurentii) was the most frequently isolated species in both environments.
- Bird excreta samples exhibited higher species diversity compared to tree hollow samples.
Conclusions:
- Identified diverse Cryptococcus species in environmental samples.
- Findings are crucial for understanding the environmental epidemiology of emerging fungal pathogens.
- Emphasizes the need for public health surveillance and cryptococcosis control strategies.
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