CHAPTER XXII 



THE RELATION OF FLIES TO SUMMER DIARRHOEA 



OF INFANTS 



The conclusive nature of the evidence that the house-fly is an 

 important factor in the spread of typhoid fever naturally directed 

 the attention of medical men and investigators to the possibility 

 of their being concerned in the dissemination of this serious intes- 

 tinal complaint of infants. Niven (1910) defines summer or 

 epidemic diarrhoea as being " a term applied to an affection 

 marked by a somewhat definite group of symptoms, in which 

 vomiting sickness, copious diarrhoea, rice-watery and green stools, 

 and finally convulsions play a conspicuous part. This condition 

 is not rarely somewhat prolonged, and is often attended with 

 some degi'ee of fever. On the one hand it shades into typhoid 

 and paratyphoid fevers, and on the other it is not rarely the termi- 

 nation of a tuberculous enteritis or some wasting affection." This 

 disease is responsible for an enormous mortality among infants 

 under two years of age, and in fact accounts for more deaths than 

 any other disease. 



In referring to epidemic diarrhoea in Portsmouth, Fraser (1902), 

 cited by Nuttall and Jepson, states that " on visiting the houses 

 in question I find that in all, almost without exception, the occu- 

 pants have suffered from a perfect plague of flies. They told me 

 every article of food is covered at once with flies.... I repeat that 

 to this, and this alone, I attribute the diarrhoea in the Goldsmith 

 Avenue district." 



Nash was one of the first medical observers to call attention 

 (in 1902) to the remarkable coincidence between the abundance of 

 flies and the prevalence of this serious infantile disease. In the 



