RT Journal
T1 THe susceptibility of rodents to plague
JF Journal of the American Medical Association
JO Journal of the American Medical Association
YR 1909
FD October 16
VO LIII
IS 16
SP 1295
OP 1295
DO 10.1001/jama.1909.02550160051009
UL http://dx.doi.org/10.1001/jama.1909.02550160051009
AB It would be reasonable to expect that in communities where plague had long existed among rodents some would recover and in future be immune to the disease, and this has been shown to be the case with rats in India.1 It is rather surprising, however, to learn that a large percentage of the rats (Mus norvegicus) in San Francisco are refractory to plague infection even when submitted to the rigorous test of inoculation with highly virulent cultures of the plague bacillus. McCoy,2 of the Public Health and Marine-Hospital Service, during his investigations of plague in the federal laboratory at San Francisco, has found that from 20 to 70 per cent, of the large (old) rats experimented on were partially or entirely immune to laboratory infection. The percentage of immunity was found, however, to be not nearly so high among the smaller (young) ones. The arguments advanced to show