Search for Clinical Evidence of an Exoerythrocytic Stage in Mice Exposed to Plasmodium gallinaceum Infection. ∗

Summary

When mice were bitten by A. aegypti mosquitoes infected with P. gallinaceum sporozoites, and portions of their spleens were subsequently implanted intra-peritoneally in clean chicks after intervals of 4 to 7 days, the latter did not develop infections in any instance. When similar implantations were made from bitten chicks, there resulted an impressive number of infections that were not easily ascribable to transfer of infected erythrocytes from the blood-stream. The evidence strongly suggests that the well-known exoerythrocytic cycle of P. gallinaceum in the chick, a species that is fully susceptible to infection with sporozoites of the organism, does not find a counterpart in the mouse, a species that is not demonstrably susceptible to such sporozoite infection.

Grateful acknowledgement is made of the technical assistance of Esther W. Nadolny.