The Demonstration of Yellow Fever Antibodies in Animal Sera by the Intracerebral Protection Test in Mice 1

Abstract

Summary and Conclusions 1. The technic for a modified intracerebral yellow fever protection test in mice is described, together with a discussion of the factors to be standardized. 2. Judgments of antibody content of a serum are best based upon a detailed knowledge of the behavior of known non-antibody containing sera of the same species in a properly balanced and controlled protection test. 3. Some groups of animals (and probably some birds) exhibit a non-specific activity against yellow fever virus, and protection tests with sera of these animals require more than the usual amount of virus. 4. Standards of negativity are established for the mammals and some of the birds of Eastern Colombia. 5. The use of the average survival time to measure protection test results is described.