Cowpox is an infection caused by a virus. It is mainly found in Europe, particularly in the UK.
The condition is caused by the cowpox virus. The cowpox virus is within the family Poxviridae and the genus Orthopoxvirus. Other orthopoxviruses that cause infections in humans include:
Cowpox virus was used to make the first successful smallpox vaccine (today, the vaccinia virus is used).
Cowpox most commonly is spread through direct contact with an infected ulcer on a cow's teat. It can also be transmitted through direct contact with an infected cat.
The virus is found in wild rodents, most commonly in bank voles, wood mice, and field voles, although transmission from these animals to humans is rare. There has been one proven case of rodent-to-human transmission. Other animals that can transmit cowpox include animals in zoos and circuses.
Person-to-person transmission has not been reported.
When a person becomes infected with the virus that causes cowpox, the virus begins to multiply within the body. After 9 to 10 days, symptoms can begin. This period between the transmission of cowpox and the start of symptoms is called the "cowpox incubation period."
Cowpox symptoms are similar to the symptoms one might experience after getting the
smallpox vaccine.
The most common symptom is a rash that develops where the skin touched the infected ulcer. This rash looks like one or more blisters, which then fill with pus, then form an ulcer, and eventually scab over with a thick black crust. Eventually, the rash will heal and scars will form. The rash does not spread.
Other symptoms of cowpox can include:
- Swelling of lymph nodes
- Red streaks from infected area to the armpit
- Throbbing pain along the affected area
- Fever
- Chills
- Loss of appetite
- Muscle aches
- Headache.
In order to make a diagnosis of cowpox, the healthcare provider will ask a number of questions about:
- Current symptoms
- History of medical conditions
- Family history of medical conditions or illnesses
- Recent exposure to animals
- Current medications.
The healthcare provider will also perform a physical exam to look for signs and symptoms of cowpox. This will include a
skin exam to look for the cowpox rash.
Before a diagnosis is made, the healthcare provider will consider other illnesses that can share common signs and symptoms with cowpox, including:
There are currently no proven treatments that can kill the cowpox virus. Therefore, treatments focus on providing relief of symptoms as the body fights the cowpox virus. This is called supportive care.
Supportive care as treatment for cowpox can include:
- Medications to control fever or pain
- Antibiotics and wound care to prevent secondary infections caused by bacteria.
In people with normal immune systems, cowpox improves within several weeks. Scars will remain, but there are no other long-term effects.
In immunocompromised adults and children (especially those with
atopic dermatitis), an infection with the cowpox virus may lead to an extensive rash over most parts of the body. In extreme cases, it can also cause death.