An Attempt to Transmit Yellow Fever Virus by Dog Fleas (Ctenocephalides canis Curt) and Flies (Stomoxys calcitrans Linn.)

Abstract

A number of insects other than mosquitoes have been incriminated as possible carriers of the virus of yellow fever. Philip (I) found that monkey lice (Pedicinus sp.) were capable of producing yellow fever when saline emulsions of one hundred or more were injected into a normal rhesus monkey immediately after their removal from infected animals. Davis and Shannon (2) found that in one instance the virus of yellow fever survived for a week in the bodies of Triatoma megista. Later Davis (3) found that Triatoma megista could produce immunity in rhesus monkeys when injected as late as ten days after an infective blood meal. Injection of triatomas seven days after an infective blood meal resulted in fever and immunity, but injection from three to six days after such a meal produced fever and fatal infection. In one experiment yellow fever virus was transmitted to a normal rhesus monkey by the bites of triatomas after an interrupted feeding on an infected animal. Monteiro (4) reported the experimental transmission of yellow fever by the feces of infected bedbugs, and stated that active virus was eliminated with the feces for as long a period as fifteen days after the infective blood meal. He also claimed that there was no multiplication of the virus within the body of the bedbug. Philip (i) found that the adult, larval, or nymphal forms of bedbugs (Cimex lectularius) did not transfer the virus of yellow fever from an infected rhesus monkey to a normal one by direct feeding. Kumm and Frobisher (5) concluded that the virus of yellow fever died off rapidly in the bedbug (Cimex hemipterus) and that the disease was not produced by injecting emulsions of bedbugs later than the second day after an infective feeding. Davis (6) found that in certain species of tick the virus of yellow fever may remain virulent for periods as long as twenty-three days. No evidence was obtained that the virus of yellow fever was transmitted by the bites of infected ticks.