Chromosome breaks and changes in the mitotic regime of human and animal cells under the influence of a measles virus vaccinal strain (L-16)]

The vaccine strain of the Leningrad-16 measles virus is capable of inducing lesions in the structure and chromosome quantity and of increasing the frequency of cells with pathologic mitosis in human fibroblast embryo culture. The measles virus produced the same effect on genetic structures in marrow cells and testicles of infected mice. No increase of cell frequency with chromosome lesions was observed in the healthy children immunized against measles.