POLIOMYELITIS AND FLIES

Press, Volume LXXXIV, Issue 25390, 13 January 1948, Page 6

POLIOMYELITIS AND FLIES

POSSIBLE PART IN DISEASE AMERICAN RESEARCH How the summer incidence of poliomyelitis has been a consistent feature of the natural history of the disease, and the possible part that flies may play in it are discussed in an article by Dr. Russell J. Blattner in the American Journal of Pediatrics. Dr. Russell Blattner says that as early as 1913 E. W. Saunders and his associates suggested the importance of flies in the epidemiology of poliomyelitis, with special emphasis on the green fly, Lucilla Caesar. Subsequently, non-biting flies collected during epidemics in widely separated parts of the United States were found to harbour the virus of poliomyelitis, regardless of the site of collection, whether rural, suburban, or urban. Dr. Blattner says that Sabin and Ward were able to isolate the virus from flies collected in urban areas during outbreaks of the disease in Atlanta and Cleveland. These investigators considered the ease with which the virus could be isolated from flies trapped at urban sites where contamination with fecal material, as in open privies, was at least not immediate, placed emphasis on the importance of flies in the epidemiology of poliomyelitis, and that flies might be responsible in some measure for the special summer incidence of the disease. At the conclusion of the article Dr. Blattner suggests that the work of Melnick and Penner, two other investigators. was of significance, since it represented the first controlled study indicating that the human poliomyelitis virus could persist in tne bodies of flies for a considerable period and that the virus could be detected in their excreta. Such experimental results lent support to the concept that the fly might play a real part in the natural history of the disease. The question whether the fly was an obligatory host or an accidental host or mechanical carrier of the virus, and likewise an explanation of the differential behaviour of the various strains of virus in the fly, had to await further investigation.