AN EXPERIMENTAL VIABLE VACCINE AGAINST PULMONARY COCCIDIOIDOMYCOSIS IN MONKEYS
ARMY BIOLOGICAL LABS FREDERICK MD
Pagination or Media Count:
Monkeys Macaca mulatta vaccinated by sub cutaneous injection in the forearm with from 10 to 10 to the 8th power viable Coccidioides immitis arthrospores were protected against respiratory challenge with approximately 7000 viable arthrospores administered six months after vaccination. Protection was evident from the healthy appearance throughout four months post-respiratory challenge negative chest X-rays at 15, 30, 60, and 120 days and only very minor histopathological pulmonary changes on autopsy at 120 days, with negative lung cultures in 80 per cent of the animals. This was in striking contrast to the outward clinical appearance of severe disease loss of weight, accelerated respiration, severe coughing, general debilitation positive X-rays massive pulmonary destruction, positive lung cultures and death of five of nine of the monkeys that were un vaccinated or had received nonviable arthrospore vaccines. The appearance of spherules very few in number, accompanied by very minor pathological changes in the lungs of some of the dissemination controls subcutaneous viable vaccination without respiratory challenge indicated possible dissemination from the primary cutaneous infection, although oral transmission from the cutaneous lesions could not be ruled out.