2003 Midwest monkeypox outbreak
Beginning in May 2003, by July a total of 71 cases of human monkeypox were found in six Midwestern states including Wisconsin (39 cases), Indiana (16), Illinois (12), Kansas (1), Missouri (2), and Ohio (1). The cause of the outbreak was traced to three species of African rodents (Gambian pouched rat, dormice, rope squirrels) imported from Ghana on April 9, 2003, into the United States by an exotic animal importer in Texas. These were shipped from Texas to an Illinois distributor, who housed them with prairie dogs, which then became infected.
| 2003 Midwest monkeypox outbreak | |
|---|---|
The outbreak included Wisconsin, Indiana, Illinois, Ohio, Kansas, and Missouri as well as an additional case in the eastern state of New Jersey. | |
| Disease | Monkeypox |
| Virus strain | "West African clade" |
| Source | African rodents (Gambian pouched rat, dormice, rope squirrels) housed with prairie dogs |
| Location | Midwestern United States |
| Index case | May 15, 2003 |
| Confirmed cases | 71 |
| Recovered | 71 |
Deaths | 0 |
| Fatality rate | 0% |
The outbreak marked the first time monkeypox infection appeared in the United States, and the first time in the Western Hemisphere. No deaths were reported, and no human-to-human transmission was found. All cases involved direct contact with infected prairie dogs. Electron microscopy and testing by polymerase chain reaction and immunohistochemistry were used to confirm the causative agent was human monkeypox.