Studies in human malaria; homologous strain superinfection during latency in subjects with sporozoite-induced vivax malaria (St. Elizabeth strain).

The appraisal of a new anti-malarial drug can be very tedious when the challenging parasite can be be one which characteristically exhibits prolonged latency. Since experience with the St. Elizabeth strain of the Plasmodium vivax has shown that its most striking activity usually occurs 9-11 months after infection, final evaluation of attempted prophylaxis or early curative therapy is often delayed for nearly a year. This paper will describe an attempt to secure earlier information as to the presence or absence of latent infection by observing the results of an intravenous inoculation of homologous strain parasites.