Coccidioides : Life Cycle

Comments:
Life Cycle of Coccidioides spp.: Here's another look at the life cycle of this fungus. In the environment, Coccidioides spp. exist as mold (1) with septate hyphae. The hyphae fragment into barrel-shaped arthroconidia (2) which get aerosolized (3) when the soil is disturbed by construction, earthquakes, weather, animals and humans. The arthroconidia are inhaled by a susceptible host (4) and, in this new environment (lungs), they develop into spherules (5). The spherules grow, develop endospores (6) and eventually rupture (7) releasing the endospores (8) into the surrounding tissues. Each endospore can develop into a new spherule, thereby continuing the infection cycle. It takes 120-132 hrs. from inhalation of arthroconidia to the rupture of mature spherules.

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