Editorial use only Swollen lymph nodes in the neck of a female patient with monkeypox during an outbreak that took place in the Democratic Republic of the Congo (DRC) from 1996 to 1997. Lymph node swelling occurs near the start of the disease, with the onset of fever and before the appearance of the characteristic rash. The monkeypox virus, which is found near rainforests in Central and West Africa, causes disease in humans and monkeys, although its natural hosts are rodents. It is capable of human-to-human transmission. In humans it causes fever, swollen glands and a rash of fluid-filled blisters. It is fatal in 10 percent of cases. In 1996, 71 suspected human monkeypox cases were reported in the DRC. Two cases were confirmed by monkeypox virus isolation from lesion material.