Identification of a hemolytic activity elaborated by Haemophilus ducreyi.

Haemophilus ducreyi is the causative agent of the sexually transmitted disease chancroid. We have identified a hemolytic activity expressed by H. ducreyi. This activity is most readily detected when horse erythrocytes are used as a target; however, low levels of activity can be detected with sheep, human, or rabbit erythrocyte targets. The activity is heat labile and protease sensitive.