The Centers for Disease Control and Prevention (CDC) has been working closely
with state and local health department and other partners to investigate cases of monkeypox virus
infections among humans who had direct or close contact with recently purchased ill prairie dogs, a
Gambian rat, and a rabbit that was housed in a veterinary clinic with an ill prairie dog. As of June
7, at least six persons with probable monkeypox infection have been reported to be veterinarians or
staff at veterinary hospitals.
Monkeypox is a rare disease that occurs naturally in the tropical rainforest areas of Western and
- It was first documented in 1958 in a colony of primates (hence the term - Monkeypox).
- The first human case was identified in 1970 in Zaire, who had smallpox-like lesions.
- Most documented human cases occurred among villagers where hunting is integral to village life.
- The natural disease hosts are likely several species of African squirrels.
Clinically in humans, monkeypox is similar to smallpox:
- The incubation period (time from exposure to disease onset) is between 7 and 15 days.
- Initially, the illness includes fever, headache, muscle aches, non-productive cough, and swollen lymph nodes.
- One to three days after the onset of fever, a rash characterized by “raised bumps” can appear.
- This rash may last for several weeks.
- It has been reported that the rash is more commonly found on a person’s arms and legs.
- Approximately, 1 to 10% of people who become ill may die.
- Most human cases had contact with ill prairie dogs.
Clinical manifestations in animals include fever, cough, conjunctivitis, swollen lymph nodes, and rash:
- Although primarily a disease of rodents and primates, other mammal species may be susceptible to infection.
Monkeypox is mainly transmitted by direct contact with an infected animal:
- This may include a bite or contact with an infected animal’s blood, body fluids, or lesions.
- Person to person transmission can also occur.
General precautions include avoiding contact with ill prairie dogs or Gambian giant rats and
thorough handwashing after any animal contact.
Pet owners who suspect that their animal may have monkeypox should contact their veterinarian
(please notify your veterinarian before transporting your animal to the clinic, so that appropriate
precautions can be taken). Owners should consider wearing a mask and gloves when handling the animal. The
animal’s bedding should be collected and bagged and brought with the animal to the veterinary clinic for
disposal as medically regulated waste. Soiled bedding should not be disposed of as household trash. Following
identification of an animal with suspect monkeypox in a household, any animals (including dogs and cats) who
may have come in contact with the sick animal should be closely observed for signs of illness for a period
of one month following the last date of exposure. Contaminated household surfaces should be cleaned and
disinfected. Standard household cleaning/disinfectants may be used in accordance with manufacturer’s
Transport of the ill animal to a veterinary clinic should be done by a single individual to limit
unnecessary exposure. At the time of animal transport, the owner should also transport the sick animal’s
bagged bedding for disposal. Care should be taken to minimize driver exposure during transport. During
transport animals should be confined in a closed container such as a cardboard box. If available, the animal
should be confined in a separate compartment of the vehicle, such as the bed of a pickup truck. Following
transport, the area of the vehicle where the animal was confined should be cleaned and disinfected. Standard
household cleaning/disinfectants may be used in accordance with the manufacturer’s instructions.
Veterinarians examining sick prairie dogs or Gambian giant rats, or other mammals that may have come in
contact with a suspected monkeypox case, should consider the diagnosis of monkeypox infection. Animals that
currently appear healthy but have been implicated as a probable source of infection for a human case should
also be treated as a suspected case of monkeypox. All suspected cases of monkeypox in animals should be
reported immediately to state or local health department officials.
Veterinarians who have been notified of an arriving animal with suspected monkeypox should admit the
animal through a separate entrance to a private room and place it in isolation; the animal should not be
admitted to a open waiting room.
When examining or euthanizing sick rodents, lagomorphs, and exotic pets, especially prairie dogs Gambian
giant rats or any ill mammal known to have been in contact with a case of monkeypox, the following
precautions should be used:
- Hand hygiene after all contact with a sick animal and contaminated surfaces.
- Use of gown and gloves for any contact with the sick animal and contaminated surfaces.
- Eye protection (e.g. goggles or face shield) if splash or spray of body fluids is likely.
- Respiratory protection including a NIOSH-certified N95 filtering disposable respirator for entering
the exam room.1 If N-95 respirators are not available for health-care personnel, then surgical masks
should be worn.
- Contain and dispose of contaminated waste in accordance with facility-specific guidelines for
medically regulated infectious waste.
- Handle used patient-care equipment in a manner that prevents contamination of skin and clothing.
Ensure that used equipment has been cleaned and reprocessed appropriately.
- Ensure that procedures are in place for cleaning and disinfecting contaminated environmental surfaces.
Any EPA-registered hospital detergent-disinfectant currently used by healthcare facilities for
environmental sanitation may be used. Manufacturer’ recommendations for dilution (i.e., concentration),
contact time and care in handling should be followed.
- Laundry (e.g., towels, clothing) may be washed in a standard washing machine with warm water and
detergent; bleach may be added but is not necessary. Care should be used when handling soiled laundry
to avoid direct contact with contaminated material. Soiled laundry should not be shaken or otherwise
handled in a manner that may aerosolize infectious particles.
All animals with suspected monkeypox infection should be humanely euthanized to prevent further spread of
the disease. Humane euthanasia options include pentobarbital injection or gas chamber using isoflurane or
halothane for most animals. For small rodent species such as mice, cervical dislocation may be considered if
performed by a trained person.
CDC is not currently recommending euthanasia of asymptomatic animals that may have been exposed to other
infected animals. Exposed asymptomatic animals should be confined to the home and not allowed to come into
contact with other animals. They should be observed for development of symptoms compatible with monkeypox for
one month. Should such symptoms develop, the animal should then be evaluated and euthanized if indicated.
A joint order from the FDA and CDC now prohibits the importation of rodents from Africa and interstate
sale of prairie dogs.
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