Circumoval and larval microprecipitation reactions in experimental and human gnathostomiasis.

ABSTRACT

Mice, rats and cats were infected either orally or percutaneously with a number of early or advanced third-stage larvae (EL3 or AL3, respectively) of G. spinigerum. Sera obtained from these infected animals and 10 human gnathostomiasis cases were tested against various developmental stages of the parasite which were prepared and used while being alive (fresh) or dead (air-dried) for the circumoval and larval microprecipitation (COP and LMP) reactions. No precipitin reactions were observed in all sera tested against unembryonated eggs, embryonated eggs and first stage larvae neither air-dried nor fresh preparations. Sera were merely reactive giving various degrees of membranous or filamentous precipitates against the air-dried preparation of AL3.