A New in Vitro Method (END) for Detection and Measurement of Hog Cholera Virus and Its Antibody by Means of Effect of Hc Virus on Newcastle Disease Virus in Swine Tissue Culture

Abstract

The new in vitro method described in the first report of this series was successfully employed for titrating hog cholera virus with highly reproducible results. The sensitivity of the method appeared to be somewhat lower than the conventional swine inoculation method. However, this disadvantage was overcome by an intermediary passage of the viral material to be tested in swine spleen culture. All the laboratory strains of hog cholera virus so far tested were found to be capable of producing this phenomenon, excepting the Lederle live vaccine strain, whereas various swine materials not containing the virus invariably failed to produce the phenomenon. The method appeared to be as effective as swine inoculation for the detection of hog cholera virus in naturally infected swine. This method was also applied to the detection and measurement of neutralizing antibodies against hog cholera virus. The mechanism of the phenomenon was discussed and it was concluded that this was an example of virus exaltation.