Toxicity of the Agents of Trachoma and Inclusion Conjunctivitis

Abstract

The toxicities of strains of trachoma and inclusion conjunctivitis viruses differing in virulence for the chick embryo were compared at different times during their growth in the chick embryo yolk sac. As measured by the ability to kill mice and to induce skin lesions in guinea-pigs, toxicity increased until the time at which embryos began to die. All strains possessed similar particle:toxin ratios. It is considered unlikely that the differing virulence of the strains depends on differences in the amount of toxin per elementary body.