Authors
Abstract
The fungus Cryptococcus neoformans is the cause of cryptococcosis in humans and animals. The disease has been linked to the exposure of patients to excreta of birds, of which the urban pigeon (Columba livia) is the most important reservoir of the fungus. Objective: Isolating C. neoformans in pigeon feces in the urban area of the municipality of Pasto (Colombia). Objetive: To isolate C. neoformans on stool of pigeons (Columba livia) in the municipality of Pasto, Colombia. Materials and methods: A descriptive transversal study was carried out in areas with high density of pigeons and great number of people. The areas included the churches located within the city which met the inclusion criteria. A culture of 128 samples of pigeon stool was performed on Sabouraud Dextrose Agar with chloramphenicol. Subsequently, a spread of thin layer of the culture where the pathogen grew was carried out and a drop of India ink was added to visualize the agent in the microscope. The variables analyzed were: presence of C. neoformans on pigeon stool and prevalence of the fungus in sampling areas, characteristics of the sample, and characteristics of the areas in which the agent was isolated. Results: The prevalence of C. neoformans within the municipality of Pasto town was 90%. Out of the total samples collected, 26.56% were positive. Significant relationship between the presence of the agent and the variables of the sample was found (p = 0.0025), fresh sample (p = 0.004), wet sample (p = 0.031), dry sample (p = 0.001), sample without contamination (p = 0.01), high light exposure (p = 0.016), low humidity of area (p = 0.001) and pigeon density (p = 0.007). The study allowed establishing the presence of C. neoformans on pigeon stool in the municipality of Pasto. Particular characteristics were found in the area and the sample which increase the likelihood of isolation.
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References
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