Differentiation of peste des petits ruminants and rinderpest viruses by neutralisation indices using hyperimmune rinderpest antiserum.

Six field isolates believed to be rinderpest viruses and 2 known strains of peste des petits ruminants (PPR) viruses were titrated in the presence of normal rabbit serum and with hyperimmune rinderpest antiserum prepared in rabbits. The known PPR viruses had indices less than 10 whereas 4 of the suspect field isolates had indices greater than a hundred. Two suspect field isolates had indices less than 20; both were collected from small ruminant wild life and are probably PPR viruses.