Chancroid is a bacterial infection caused by the bacterium Haemophilus ducreyi. It primarily spreads through sexual contact and is characterized by painful sores or ulcers on the genital area. These sores can be accompanied by swollen lymph nodes in the groin, which may also become painful. Diagnosis of chancroid is typically made through a physical examination and laboratory tests. Treatment usually involves antibiotics, which can effectively clear the infection. Preventive measures include practicing safe sex and regular screenings for sexually transmitted infections (STIs).