Cross Reactions in Human and Simian Malaria

Abstract

THE DETECTION of antibody in humans infected by various species of malarial parasites has presented a problem for more than 50 years. Of all the tests, the complement-fixation reaction has provided the most information, but even with this test the chief difficulty has been the lack of a standardized specific antigen of sufficient sensitivity. During the course of complement-fixation studies of malaria, certain investigators have noted cross reactions. In 1927, Kingsbury 1 reported that Plasmodium falciparum antigen reacted to about the same degree with P vivax antisera as with P falciparum antisera. However, the same amount of cross reaction did not occur when P vivax antigen was used. In this instance, the P vivax antigen detected the presence of antibody in 67% of the P vivax cases but in only 31% of the P falciparum cases. Some years later Eaton and Coggeshall, 2 using antigen prepared from the parasite,