16 



CIRCULAR 4 2 3, U. S. DEPARTMENT OE AGRICULTURE 



TULAREMIA 



Tularemia is a disease that is extremely fatal to rabbits and hares, 

 and transmissible to man by the bite of an infected tick or other blood- 

 sucking insect, or through contact with the carcass of infected ani- 

 mals. The tularemia organism {Bacterium tularense) has been recog- 

 nized only since 1921, when it was first described by the United States 



Figure 14. — Even leather is acceptable food to rats on occasion, as one sporting-goods 

 dealer learned to bis sorrow. 



Figure 15. — Disease-laden footprints of a rat showing that this rodent is a potential car- 

 rier of harmful bacteria to human food. Photograph made by allowing the rat to run 

 across a plate of agar, after which the plate was put into an incubation oven, causing 

 growth of the bacteria deposited by the rat, the organisms outlining on the agar the 

 tracks left by the rat. 



Public Health Service. The death rate is only about 4 percent, but the 

 recovery from the disease is slow, sometimes requiring 3 to 6 months. 

 Tularemia has several times been founds in rats — an added reason for 

 rat extermination. 



RABIES 



Rabies, or hydrophobia, is primarily a disease of dogs but affects 

 other animals, including rats, and is transmitted by the bite of a rabid 

 animal. Though rats have only a minor role in the spread of rabies, 

 their elimination would remove one possible source of infection. 



