THE Wairarapa Age MORNING DAILY. MONDAY, FEBRUARY 25, 1907. HOW RATS DISSEMINATE PLAGUE.

Wairarapa Age, Volume XXIX, Issue 8367, 25 February 1907, Page 4

THE Wairarapa Age MORNING DAILY. MONDAY, FEBRUARY 25, 1907. HOW RATS DISSEMINATE PLAGUE.

That the rodent is an active agent in the propagation [of plague has been a steadfastly maintained theory among scientists for many years past, but exactly how an epidemic is disseminated among the rats, and also communicated therefrom to human beings, it hag been left to the Special Plague Commission appointed by the Indian Government to determine. This scientific Commission is still engaged in its undertaking, but the discoveries that have already been taade are of such paramount importance, that a short and interim report upon the subject has been published. In the course of this proceeding the Commissioners definitely state that the disease is conveyed from one rat to another, and also to human beings by the parasite, commonly known as the "rat flea." This hypothesis has been confirmed as the result of several experiments. When plagueinfected, and healthy rats were incarcerated separately in wire cages, thereby preventing them coming into contact with one another, the healthy rodents became infected, and it was also ascertained that guinea pigs could also becotae contaminated in the same manner. But, on the other hand, if the plague-stricken rats, immune, however, from the flea, were confined and permitted to come into free physical contact with healthy animals, no such signs of infection were observed. Directly the fleas were introduced, the animals in a short time were all similarly

affected, the progress of the epidemic varying in direct proportion to the number of fleas present. These tests conclusively proved that the parasite was the active agent in propagating the disease, since every precaution was adopted to prevent the possibility of infection being spread atmospherically. Moreover, similar tests were repeated in plague-infected houses. For instance, guinea pigs were permitted to run freely in a house, which though it had been disinfected still ] ! harboured parasites, with the result that the i animals were found to be soon attacked by the fleas and contracted plague, and the parasites caught on their bodies were found to be capable of spreading the epidemic. When, however, under the same conditions, the. guinea pigs were immured in cages of wire gauze, thereby preventing the infesting of fleas, no ill' results attended the animals. There is one important theory advanced in the preface to this report—that the plague itself may in reality be a disease of fleas.