Experimental infections of vervet monkeys (Cercopithecus pygerythrus) withthree spotted fever group rickettsiae

Vervet monkeys inoculated subcutaneously or intravenously with Rickettsia c onorii, R. helvetica or R. massiliae developed rickett-saemia and seroconve rted although no clinical, haematological or biochemical evidence of infect ion was detected. The R. conorii inoculation study indicates that vervet mo nkeys are nor a suitable model for human infections with pathogenic spotted fever group rickettsiae and, therefore, the studies with R. helvetica and R. massiliae cannot be used to predict the pathogenicity of these organisms in humans.