Monkeypox virus particle, illustration. Monkeypox is a zoonotic virus from the Poxviridae family that causes monkeypox, a pox-like disease. At the centre of the monkeypox virus is a core nucleoprotein (blue) that contains the DNA (deoxyribonucleic acid, yellow) genome. This is surrounded by an outer envelope that is covered with surface tubules (purple). This 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 per cent of cases.