Malignant catarrhal fever virus specific secretory IgA in nasal secretions of wildebeest calves.

Wildebeest IgA was isolated from nasal secretions and precolostrum. It was identified by cross-reaction with anti-human and anti-bovine IgA sera. Nasal secretions collected from wildebeest calves over 3 months old had malignant catarrhal fever virus neutralizing antibody activity. They also contained specific IgA to the virus as detected by indirect immunofluorescence. It is suggested that production of malignant catarrhal fever virus specific IgA in the nasal cavity, contributes to the elimination and cessation of the virus shed in the nasal secretions of wildebeest calves over 3 months. old.