During May and June 2003, health officials and scientists investigated several reports of monkeypox among residents of Wisconsin, Illinois, Indiana, Kansas, Missouri, and Ohio who became ill after having contact with sick prairie dogs. In total, 79 persons became ill with monkeypox during this time. The disease is caused by the monkeypox virus, which belongs to the orthopoxvirus group of virus. Other viruses in this group that can cause infection in humans include variola (smallpox), vaccinia (used in smallpox vaccine), and cowpox viruses.
The prairie dogs were believed to have acquired the monkeypox virus following
contact with infected rodents (Gambian giant rats, dormice, and others)
imported from Africa as exotic pets. This was the first evidence of community-acquired
monkeypox virus infection in the United States. There were no reported
cases of monkeypox in Minnesota.
Clinical features of monkeypox in humans are similar to those of smallpox. The illness usually begins with a fever, headache, muscle aches and tiredness or lethargy approximately 12 days after exposure. There is also associated swelling of lymph nodes, a feature that may help differentiate it from smallpox. The patient develops a rash a few days after onset of fever, which usually starts on the face and then progresses to involve other parts of the body. The rash develops through several stages starting out as raised bumps that become fluid filled and eventually crust over and fall off. The illness usually lasts two to four weeks, there is no specific treatment, however it rarely leads to death.
Monkeypox can be acquired by direct contact with an infected animal's blood, body fluid or lesions, or by the bite of an infected animal (see Monkeypox in Animals: The Basics for People Who Have Contact with Animals for more information about contact with animals). The disease can also be spread by person to person contact but is much less infectious than smallpox.
Health care providers evaluating individuals for suspected monkeypox
should observe Standard,
Contact and Airborne Infection Control Precautions.
Monkeypox should be suspected in individuals who develop a fever and rash illness and report recent contact with prairie dogs.
Please call the Minnesota Department of Health
immediately (651-201-5414 or toll free 1-877-676-5414) to
report a suspect case of monkeypox.