SULKIN AND ALLEN 



The isolation of rabies virus from naturally infected insectivorous 

 bats in the United States inrecent years has focused the attention of 

 epidemiologists and virologists on the Chiroptera as still another 

 reservoir host for this virus in nature. Since our laboratory reported 

 the first human death believed to have been due to the bite of a 

 naturally infected bat (SulkinandGreve,1954),webecame interested 

 in the association of bats with rabies and more especially in how 

 these animals are able to survive infection with this hitherto pre- 

 sumed fatal viral infection. Investigators in South America and 

 Trinidad demonstrated that the vampire bat could suffer sustained 

 infections with rabies virus and pass the virus through infected 

 saliva to susceptible animals without themselves showing overt 

 symptoms or succumbing to thedisease(Enright,19 56). Wenow have 

 experimental evidence that insectivorous species of bats native to 

 the United States may be infected with rabies virus and never show 

 symptoms of the disease even though virus can be demonstrated in 

 brain as well as other tissues (Sulkin, 1962), 



RABIES STUDIES IN INSECTIVOROUS BATS 



Studies on the course of experimental rabies infection in insecti- 

 vorous bats were undertaken with the view to determining the sus- 

 ceptibility of these animals to peripheral inoculation with rabies 

 virus and to ascertain which tissues were involved in the infection 

 (Sulkin et al., 1959). We have also attempted to determine the in- 

 fluence of certain physiological characteristics of the bat on experi- 

 mental rabies infection in these animals (Sulkin et al., 1960; Sims, 

 Allen and Sulkin, unpublished data). In this regard, the phenomenon 

 of hibernation was the first area to receive attention. 



Species of bats which inhabittemperate zones are efficient hiber- 

 nators who remain quiescent for several months of the year. It has 

 been suggested that this conservation of energy is the reason why 

 these mammals, despite their small size, are relatively long-lived 

 (Griffin, 1958). Also, many investigators (Rasmussen, 1923, 1924; 

 Remillard, 1958; Johansson, 1959, 1960; Kayser, 1961) believe that 



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