Monkeypox in the United States
Monkeypox in the United States first occurred in 2003, when several people reported that they became ill after having contact with sick pet prairie dogs. The outbreak most likely occurred after a shipment of animals from Ghana was imported to Texas.
Monkeypox is a rare disease caused by the monkeypox virus, a member of the same group of viruses as the smallpox virus. The monkeypox virus can spread from animals to humans and sometimes from one person to another. In humans, monkeypox causes fever, headache, backache, and swollen lymph nodes, followed by a blister-like rash. In some cases, monkeypox can cause death.
In early June 2003, monkeypox was reported among several people in the United States who got sick after having contact with sick pet prairie dogs. This was the first outbreak of human monkeypox in the United States.
Traceback investigations have implicated a shipment of animals from Ghana that was imported to Texas on April 9 as the probable source of introduction of monkeypox virus into the United States.
The shipment contained approximately 800 small mammals of 9 different species, including 6 genera of African rodents. These rodents included rope squirrels (Funiscuirus sp.), tree squirrels (Heliosciurus sp.), Gambian giant rats (Cricetomys sp.), brush-tailed porcupines (Atherurus sp.), dormice (Graphiurus sp.), and striped mice (Hybomys sp.).
Gambian rats from this shipment were kept in close proximity to prairie dogs at an Illinois animal vendor implicated in the sale of infected prairie dogs. CDC laboratory testing of some animals demonstrated that 1 Gambian giant rat, 3 dormice, and 2 rope squirrels from the April 9 importation were infected with monkeypox virus.