The present status of vaccination against coccidioidomycosis in man.

Vaccines of killed whole cells of Coccidioides immitis have been injected intramuscularly in 97 human subjects to determine the safety and tolerable dose of vaccine and certain immunologic responses. Seventy-eight individuals received the whole killed spherule preparation; 18 received killed mycelial vaccine. The maximum tolerable dose of spherule vaccine was approximately 5 mg. Systemic effects were slight though in two prior coccidioidin reactors a moderate febrile illness and sbustantial antibody production followed vaccination with killed spherules. The vaccines irregularly induced antibody or delayed hypersensitivity to coccidioidin or spherule antigen. Greater antigenic mass perhaps as a soluble preparation may be needed for consistent immunologic stimulation though the spherule vaccine may be protective despite absence of detectable antibody or sensitivity to coccidioidin.