Laboratory toxicity test of field trial typhoid vaccines.

It is important for the control of vaccines to develop methods for testing their toxicity in the laboratory. Two typhoid vaccines that had given different rates of reactions among vaccinated persons in extensive field trials provided a unique opportunity for exploring the validity of the laboratory assessment of their toxicity. An elaborate design of a toxicity test based on weight changes in intraperitoneally vaccinated mice is described in this paper. The results of the laboratory test reflected the experience gained in field studies.