Infestation of Wistar rats with Tunga penetrans in different microenvironments.

Tungiasis is a zoonotic ectoparasitosis that causes considerable morbidity in affected populations. The type of microenvironment that facilitates infestation of hosts by Tunga penetrans has not been investigated. In this study, we exposed 30 laboratory-raised Wistar rats, a suitable model for the infestation, at six different places characterized by different microenvironments in a hyperendemic fishing village in northeastern Brazil. During a period of two weeks, the animals were monitored and the number of embedded fleas was documented. The number of lesions varied considerably according to the microenvironment and was highest in a cage placed at the far end of a compound of a household affected by tungiasis. No penetration was observed inside houses. Results indicate that in this endemic area transmission of T. penetrans seems to occur mainly outdoors.