Pathogenesis of Coccidioides immitis in monkeys

Area of Science:

• Mycology
• Pathology
• Infectious Diseases

Background:

• Coccidioides immitis is a fungus causing coccidioidomycosis.
• Understanding its pathogenesis in animal models is crucial for human disease research.

Purpose of the Study:

• To investigate the pathogenesis of Coccidioides immitis in monkeys following respiratory exposure.
• To compare the effects of arthrospores from different growth media.

Main Methods:

• Monkeys were exposed via inhalation to varying doses of Coccidioides immitis arthrospores.
• Clinical signs, pathological changes, X-rays, and serological tests were monitored.
• Fungal presence was confirmed through cultural methods.

Main Results:

• 100% infectivity was observed with doses ranging from 50 to 10,000 arthrospores.
• High doses led to acute coccidioidal pneumonia and death; low doses resulted in small, fibrous lesions.
• Pathological findings correlated with X-ray and serological data.

Conclusions:

• Respiratory exposure to Coccidioides immitis arthrospores induces dose-dependent pathogenesis in monkeys.
• The study highlights the potential for severe pulmonary disease and confirms the parasitic phase within lesions.