Horse: a potential source of Cryptococcus neoformans and Cryptococcus gattii in Egypt

Area of Science:

• Veterinary Mycology
• Zoonotic Diseases
• Molecular Epidemiology

Background:

• Cryptococcosis is a significant opportunistic mycozoonosis affecting various hosts globally.
• In equines, cryptococcosis is rare, with reported cases of rhinitis, sinusitis, pneumonia, and meningitis.
• Limited epidemiological data exists on cryptococcal infections in horses in Egypt.

Purpose of the Study:

• To investigate the occurrence of Cryptococcus species in Egyptian horses.
• To determine the role of horses in the epidemiology of cryptococcosis in Egypt.
• To identify Cryptococcus species and their virulence genes in horses, humans, and soil.

Main Methods:

• Collection of 223 samples: 183 nasal swabs from horses, 28 from humans, and 12 soil samples.
• Bacteriological examination and identification of Cryptococcus spp.
• Molecular serotyping using multiplex PCR and detection of virulence genes (LAC1, CAP59, PLB1) via PCR.
• Sequencing and phylogenetic analysis of Cryptococcus gattii gene.

Main Results:

• Overall occurrence of Cryptococcus spp. was 9.3% in horses, 25% in soil, and 10.7% in humans.
• Identified Cryptococcus gattii (B), Cryptococcus neoformans, and hybrids in horses.
• Cryptococcus gattii (B) was found in soil, and Cryptococcus gattii and Cryptococcus neoformans in humans.
• Virulence genes (LAC1, CAP59, PLB1) were detected in both C. gattii and C. neoformans isolates.
• Phylogenetic analysis showed close relatedness among C. gattii genes from horses, humans, and soil.

Conclusions:

• This study offers the first insights into Cryptococcus species ecology in Egyptian horses.
• Horses act as asymptomatic carriers, potentially disseminating pathogenic Cryptococcus spp.
• The findings highlight the potential risk of cryptococcosis infection in humans from equine sources.