ENTEROVIRUSES IN ALASKA 



Parasitological philosophy has developed the concept that the 

 more successful and probably more ancient host- parasite relation- 

 ships are those in which the host rarely becomes seriously diseased 

 by the presence of the parasite, and the parasite is able to persist 

 in or on the hostdespite tissue or humoral reaction. As a group, the 

 enteroviruses qualify eminently as successful parasites. These are 

 the general characteristics of enteroviral infections: 



(1) The incidence of infection in an exposed population group is 

 very high, 



(2) Infections are frequently asymptomatic, usually benign or 

 transitory, rarely debilitating or fatal to the host. 



(3) The host frequently becomes a carrier, disseminating virus 

 for a long period of time, particularly in the feces. 



(4) Serologically immune hosts can become reinfected enterically 

 and disseminate virus, 



(5) The various types of viruses are antigenically dissimilar to 

 the extent that heterologous immunization of the host is slight or 

 absent, but biological interference between virus types does occur. 



In addition, enteroviruses are known to be highly persistent in nat- 

 ural environment, particularly when mixed with organic matter 

 stabilized by cations and in a menstruum of low biological activity 

 such as mightbe caused by low ambient temperature. We shall speak 

 of each of these points in turn. 



There is ample evidence to show that enteroviruses, in general, 

 are spread rapidly. Eklund and Larson (1959), in their study of the 

 January 19 54 epidemic of poliomyelitis on St. Paul Island, showed 

 that the infection had pervaded the community to a major extent with- 

 in 18 days. Their thorough study led them to believe that the virus 

 may have been spread, to a large extent, from oropharyngeal secre- 

 tions, either by droplets disseminated by coughing and sneezing, or 

 by saliva exchange in the use of common utensils. Bhatt, Brooks, 

 and Fox (1955), in their detailed viro- epidemiological surveillance 

 of poliomyelitis infections in Louisiana, concluded that polioviruses 



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