The relative susceptibility of Anopheles quadrimaculatus and two strains of A. albimanus (Panama and Florida Keys strains) to three strains of Plasmodium vivax was determined. The strains of vivax included a U. S. strain (St. Elizabeth), a New Guinea strain (Chesson), and vivax of Korean origin.
In all cases A. quadrimaculatus showed a high degree of susceptibility, while the two strains of albimanus either were completely non-susceptible, as in the Korean vivax, or became infected only occasionally and at a very low rate.
The infectivity of Korean vivax to A. quadrimaculatus, and transmission through that species, confirms the possibility of establishment of malaria from that area in this country.