Abstract
Leptospira interrogans serovar balcanica was haemolytic for washed human, cattle, sheep and possum red blood cells (RBC); serovar hardjo was non-haemolytic. A test for haemolysis may prove useful in the preliminary differentiation of balcanica and hardjo isolates. Balcanica was non-haemolytic for unwashed RBC from human and bovine donors whose serum contained Hebdomadis serogroup antibody. Haemolytic activity tended to disappear with repeated subculture of balcanica.