A complement fixation test for antigens of and antibodies to malignant catarrhal fever virus

A complement fixation test was developed for the study of malignant catarrhal fever (MCF). A clarified ultrasonicate of cultured cells infected with MCF virus was used as antigen and detected increasing levels of complement fixing antibody in 12 out of 14 and four out of nine infected cattle and rabbits respectively. Titres greater than or equal 1:64 were found in hyperimmune sera from three out of four cattle, five out of five rabbits and in eight out of 143 wildebeest. No antibody was detected in 310 normal cattle sera from areas of Kenya with endemic MCF. The test did not detect viral antigens in a number of infected tissues or increased anticomplementary activity in sera from sick animals.