H. ducreyi enters skin through microabrasions incurred during sexual intercourse. The incubation period of H.ducreyi infection is 10 to 14 days after which there is progression of the disease. A local tissue reaction leads to development of erythomatous papule, which progresses to pustule in 4–7 days. It then undergoes central necrosis to ulcerate.
Chancroid
Genital herpes
Tinea manuum
Demodicosis
Tinea faciei
Lentigo simplex
Tinea capitis
Melanosis coli