Allergy to flea bites. III. The experimental induction of flea bite sensitivity in guinea pigs by exposure to flea bites and by antigen prepared from whole flea extracts of Ctenocephalides felis felis

Abstract

Guinea pigs were sensitized to flea bites by previous exposure to Ctenocephalides felis felis. Delayed reactions appeared at from 5–7 days following daily exposures. Two to 5 days following the appearance of delayed reactions, the animals showed both delayed and immediate types of reactivity. The induction of sensitivity by flea bites was independent of the number of fleas biting. Sensitivity to flea bites induced either by intradermal injection of whole flea extract in saline or by flea bites was systemic and appeared to be an allergic phenomenon. Sensitivity of guinea pigs to flea bites was induced by intradermal injections of whole flea extracts in saline. Guinea pigs injected intradermally with whole flea extract reacted to flea bites. Conversely, when sensitized by flea bites, they reacted to challenge with the extract. While sensitivity to flea bites induced by flea bites required a latent period of 5–7 days, sensitivity to flea bites induced by whole flea extract required 10–14 days.