AN ATTEMPT TO INFECT HUMAN BODY LICE,PEDICULUS HUMANUS VAR CORPORISON A MILD CASE OF MURINE TYPHUS*

A patient with a sporadic mild case of ty-phus fever assume on epidemiological and cli-nical grounds to be murine typhus was test.edfor his infectivity for normal adult human bodylice, Pediculusi humanus va.r corporis, during aperiod of 5 days from the 9th through 4he 13;thor last day of the disea.se. One out of 105 mice(0.95'/o) was later found to have developed asmall numbeir o,f morphologically and tincto-rially typical ricketts.iae. A guinea pig, whichwas inoculated in succes.sion with two suspen-sions of ground lice showing and n;olt showingdefinite rickettsia.e in smears, twice gave ne-gative complement fixation with epidemic anti-gen but positive fixation with murine antigenat a titer of l:40. As far as the authors. areawa.re, this is the first report to show that byfeeding on a mild case of murine typhus, lic;ebecame infected with typhus rickettsiae whichproved serologically to be R. mooSieri. It istherefore suggested that under nat.ural condi-tions when lice feed continuously on severe casesof murine typhus throughouit the febrile disease,a sufficiently higher percent of lice may becomeinfected with sufficiently larger numbers oftyphus ricketts.iae to give rise to outbreaks oflouse-borne typhus in Iouse-infested communi-ties.