Chancroid (Haemophilus ducreyi)

Etiology and Epidemiology

Chancroid is caused by Haemophilus ducreyi, a fastidious gram-negative bacillus. It is prevalent in many developing countries but occurs sporadically in the developed world. Most Western cases occur in returning travelers (90% are male) from endemic areas or occasionally in localized urban outbreaks associated with commercial sex workers. Chancroid is a risk factor for transmission of HIV. Diagnosis of chancroid in infants and children is strong evidence of sexual abuse. Male circumcision lowers the risk for chancroid. The incidence of chancroid has declined significantly since 1981 and remains low in the United States.