Abstract
Summary
The virulence of ICH virus has been effectively modified by serial propagation in dog-kidney cultures followed by adaptation to and serial cultivation in swine-embryo tissue. The modified virus is an effective immunizing agent, and produces in the vaccinated animal no adverse reaction except for an occasional case of light and transient opacification of the eye following massive peripheral injection of the virus. The modified ICH virus may spread through the urine of vaccinated animals to intimate contact animals, but although these develop antibodies they show no signs of disease. A combined vaccine prepared by mixing modified CD and ICH viruses elicited good protection against both diseases in doubly susceptible animals, and in puppies already immune to ICH did not interfere with the production of immunity to CD.
Get full access to this article
View all access options for this article.