Mpox, formerly known as monkeypox, is a rash illness caused by the mpox virus, which belongs to the same group of viruses as smallpox. Mpox is rare in the United States. The disease is most commonly reported in people living in or traveling to certain central and west African countries. Prior to May 2003, human mpox had never been identified within the Western Hemisphere. At the end of May 2003, human cases of mpox were identified in the United States associated with direct or close contact with prairie dogs, a Gambian giant rat, and a rabbit. Investigations identified a common distributor where prairie dogs and Gambian giant rats were housed together in Illinois. The Gambian giant rats had been imported from Ghana in a shipment containing approximately 800 small mammals, and several of these mammals tested positive for the mpox virus. This indicated that this shipment was the likely source of the 2003 United States mpox outbreak. As a result of this outbreak, the Food and Drug Administration (FDA) banned the importation of African rodents.
The first confirmed U.S. case in this outbreak was announced on May 18, 2022. Since that date, additional cases have been identified in the U.S. Cases have also been identified in other countries where the disease is not usually found. Public health officials are investigating how these people became infected. Some, but not all cases, have been identified among people who self-identify as men who have sex with men (MSM). It is not clear how people in those clusters were exposed to the mpox virus. At this time, the risk of infection to the public is considered to be low.
The Centers for Disease Control and Prevention (CDC) and the West Virginia Bureau for Public Health (BPH) are taking steps to respond to this emerging situation. On May 20, 2022, CDC issued a health alert network (HAN) health advisory to raise awareness among healthcare providers, public health officials, and the public. BPH will investigate any reported suspect cases and facilitate laboratory testing through the CDC. BPH approval is required before sending any specimens. If monkeypox cases are identified in West Virginia, local health departments will monitor close contacts of the case for 21 days after their last exposure.