Chancroid (Haemophilus ducreyi)
A sexually transmitted disease characterized by painful genital ulceration and inflammatory inguinal adenopathy. The disease is caused by infection with Haemophilus ducreyi.
Isolation of H. ducreyi from a clinical specimen
Probable: a clinically compatible case with both a) no evidence of Treponema pallidum infection by darkfield microscopic examination of ulcer exudate or by a serologic test for syphilis performed greater than or equal to 7 days after onset of ulcers and b) either a clinical presentation of the ulcer(s) not typical of disease caused by herpes simplex virus (HSV) or a culture negative for HSV.
Confirmed: a clinically compatible case that is laboratory confirmed