Establishing a laboratory colony of the human flea, Pulex irritans: methods for collecting, rearing, and feeding.

Background: Colonizing fleas under laboratory conditions is a crucial step to studying their biology, conducting bioassays, and evaluating their ability to transmit pathogens. Starting a colony implies collecting and maintaining wild-caught specimens to obtain the next generations. Here we describe methods to collect, safely transport, and maintain adult and immature stages, and for the first time, to produce viable next generations of Pulex irritans, the human flea in the insectary.

Methods: Adult fleas were collected using human landing catches, while immature stages were obtained using the Berlese-Tullgren method. Blood feeding was performed using an artificial feeding device and the survival of adult fleas maintained on human or sheep blood was assessed.

Results: More than 200 F0 adults survived and produced eggs for approximately 6 weeks, with an average lifespan of 6 days for males and 10 days for females. Pupation occurred around 10 days after arrival in the laboratory, yielding more than 900 cocoons within 8 weeks, with an emergence rate of approximately 80%. Challenges included high mortality among F1 adults, with both sexes surviving an average of 7 days. Although blood source assay was inconclusive, fleas were maintained on human blood. Factors that may have contributed to the low survival of F1 are discussed.

Conclusions: This study provides a foundational framework for laboratory-based research on P. irritans and its role in vector-borne disease transmission. While further studies are needed to establish a sustainable laboratory colony, we demonstrate that a substantial F1 population can be obtained within 3 weeks of laboratory rearing, enabling experimental studies on this species.