The incidence of chancroid in the United States is small, with less than one thousand cases reported each year. Chancroid is caused by the bacterium Hemophilis ducreyi, a gram-negative bacillus. Testing for chancroid involves taking a sample of tissue from the chancroid lesion (described below).
The incubation period of H. ducreyi is 3 to 10 days.
Chancroid is characterized by the development of an extremely painful lesion that appears, typically, in the urogenital region. Initially the lesion looks like a raised bump that continues to grow and ulcerate over a 1 to 2 day period. The lesion, as stated before, is painful as well as soft, with jagged edges, and its base may develop a yellow or gray exudate. About half of people infected with H. ducreyi will develop lymphadenopathy.
Treatment for chancroid is with antibiotics. Partners should be treated whether or not they have developed a lesion. In addition, since chancroid is correlated with human immunodeficiency virus (HIV) infection, the patient and his or her partners should be tested for HIV as well.