Cowpox refers to a disease that is caused by the cowpox or
The virus is a member of the orthopoxvirus family. Other
viruses in this family include the smallpox and
vaccinia viruses. Cowpox is a rare disease, and is mostly
noteworthy as the basis of the formulation, over 200 years
ago, of an injection by Edward Jenner that proved
successful in curing smallpox.
The use of cowpox virus as a means of combating smallpox,
which is a much more threatening disease to humans, has
remained popular since the time of Jenner.
Once a relatively common malady in humans, cowpox is now
confined mostly to small mammals in Europe and the United
Kingdom. The last recorded case of a cow with cowpox was in
the United Kingdom in 1978. Occasionally the disease is
transmitted from these sources to human. But this is very
rare. Indeed, only some 60 cases of human cowpox have been
reported in the medical literature.
The natural reservoir for the cowpox virus is believed to be
small woodland animals, such as voles and wood mice. Cats and
cows, which can harbor the virus, are thought to be an
accidental host, perhaps because of their contact with the
voles or mice.
The cowpox virus, similar to the other orthopoxvirus, is best
seen using the electron microscopic technique of
negative staining. This technique reveals surface details. The
cowpox virus is slightly oval in shape and has a very
Human infection with the cowpox virus is thought to require
direct contact with an infected animal. The virus gains entry
to the bloodstream through an open cut. In centuries past,
farmers regularly exposed to dairy cattle could acquire the
disease from hand milking the cows, for example. Cowpox is
typically evident as pus-filled sores on the hands and face
that subsequently turn black before fading away. While
present, the lesions are extremely painful. There can be scars
left at the site of the infection. In rare instances, the
virus can become more widely disseminated through the body,
resulting in death.
Both males and females are equally as likely to acquire
cowpox. Similarly, there no racial group is any more
susceptible to infection. There is a predilection towards
acquiring the infection in youth less than 18 years of age.
This may be because of a closer contact with animals such as
cats by this age group, or because of lack of administration
of smallpox vaccine.
Treatment for cowpox tends to be ensuring that the patient is
as comfortable as possible while waiting for the infection to
run its course. Sometimes, a physician may wish to drain the
pus from the skin sores to prevent the spread of the infection
further over the surface of the skin. In cases where symptoms
are more severe, an immune globulin known as antivaccinia
gamaglobulin may be used. This immunoglobulin is reactive
against all viruses of the orthopoxvirus family. The use of
this treatment needs to be evaluated carefully, as there can
be side effects such as kidney damage. Antibodies to the
vaccinia virus may also be injected into a patient, as these
antibodies also confer protection against cowpox.