Similarity of Australian "Q" Fever and a Disease Caused by an Infectious Agent Isolated from Ticks in Montana

Abstract

Report of a comparative study of these infections. One human case of the Montana infection was similar to the description of "Q" fever. Cross immunity tests (guinea pigs) showed complete cross immunity between the 2 infections. Protection tests using sera of "Q" fever cases and serum from one case of the Montana infection showed equal protection of all these sera against virus of the Montana infection. Neither of the two infections produces agglutinins for Proteus X although rickettsiae have been found associated with both. The 2 infections are closely related.