What is Cowpox?

Vaccinia is an infectious disease that occurs in cattle. It is an acute infection caused by bovine variola virus. Its symptoms are usually localized ulcers in the breasts of cows. The virus can be transmitted to humans through contact. It is more common in milkers and slaughterhouse workers. Papules appear on the skin of patients. These papules slowly develop into blisters, pustules, and other symptoms. Historically, the disease has occurred in Europe, especially in the United Kingdom. The virus can be found in cattle, cats and voles. Human cases are rare, with an incubation period of 9 to 10 days, but for patients with immune system defects, infection with vaccinia virus is fatal. According to current WHO reports, the disease has now disappeared globally.

Basic Information

English name: vaccinia; cowpox
Visiting department: Infectious Diseases
Multiple groups: Milker, slaughterhouse worker
Common locations: skin

Common causes: Infection factor
Common symptoms: Pimples, blisters, pustules
Contagious: Have
way for spreading: direct contact

Causes of vaccinia

Infection factor

Cowpox virus is caused by cowpox virus. It is similar to poxvirus and can cause hemorrhagic damage when cultured on chicken embryo cysts. Similar to vaccination. Epidermal chronic necrosis, more bleeding, large inclusions in the cytoplasm can be seen in the cells below the epidermis.

2. Occupational factors

This disease is caused by acute infection of bovine nipples and breasts caused by bovine infection with variola virus, and can be transmitted to humans through contact. Therefore, this patient group is more common in milkers and slaughterhouse workers.

Vaccinia clinical manifestations

Symptoms

The incubation period is usually 12 days. The onset is acute. The body temperature suddenly rises to 39 ° C to 40 ° C. There are symptoms such as irritability, headache, sore throat, sore limbs, chills, vomiting, and loose stools. . After 2 to 4 days, the rash is complete. The rash is centrifugal, with more head, face, and extremity proximal ends, and less torso. At first, it is dark red small pits, and there are pimples within a few hours. After 2 to 3 days, the rash occurs. The blisters gradually become blisters, and the surrounding area is flushed. After 5 to 8 days, the herpes grouting gradually becomes pustules, with pain, and the surrounding blushes deepen. At this time, the temperature rises again, which is called "purulent fever", to 10 ~ 14. On days, the temperature gradually decreased, and the pus was gradually shrinking or rupturing and crusting, eventually forming a crust cap. After 2 to 4 weeks, the cuff cap naturally fell off, itchy, and leaving blister marks, called "numb spots".

2. Signs

The incubation period is 5-7 days. Primary damage occurred at the contact site. It started as a pimples and quickly turned into blisters and pustules. The center of the blisters was umbilical depression with redness and edema around. Occurs on fingers, forearms and face. Fever, with local lymphadenitis and lymphangitis. Can heal in 4-6 weeks.

Vaccinia Inspection

1. It can be diagnosed based on the history of exposure to cattle and typical rash, and can be confirmed by virus culture.

2. Pathological changes: Similar to vaccinia, but the epidermal necrosis is slower, inflammation, erythema is obvious, there is more bleeding, the epidermal basal cells are hypertrophic, and cytoplasmic inclusions can be seen in the lower cells of the epidermis. The inclusion body should be large.

Differential diagnosis of cowpox

According to the clinical manifestations of this disease, it needs to be distinguished from milker's nodules, sheep pox, primary skin tuberculosis, foreign body granulomatosis and sporotrichosis. The focus is on the identification of nodules in milkers. The latter is a parapox virus infection with an incubation period of 5 to 14 days. Single or several inflammatory pimples begin to appear on the hands and forearms, and later become purple-red hemispherical nodules with reddish halo around them, umbilical fossa-like center, tough texture, the size of soybeans, smooth surface, and scattered distribution without fusion. Sometimes there is a blister or pustule on the top, which later becomes crusted or gradually develops into a papilloma-like pale red lesion similar to a purulent granuloma. Therefore, it can be clearly identified based on clinical characteristics and pathological examination.

Vaccinia Complications

The disease is self-limiting and generally heals on its own in about 10-15 days. The complications are mainly damage to the integrity caused by skin damage, exposed wounds, and the formation of superficial ulcers, accompanied by obvious itching. Therefore, skin bacterial infection or fungal infection can be induced by scratching of patients, usually secondary to patients with low constitution, or long-term use of immunosuppressive agents and fungal infections such as onychomycosis. If the bacterial infection is complicated, fever, swelling, ulceration and Purulent discharge and other manifestations. Severe cases can cause sepsis and should be brought to the attention of clinicians.

Cowpox Treatment

Symptomatic treatment to prevent secondary infection, use immunoglobulin or interferon gamma, beta as appropriate.

Vaccinia prognosis

Encourage patients to maintain a comfortable mood, have an optimistic, open-minded spirit, and a strong confidence to overcome disease. Pay attention to rest, reasonable diet, diet should be light, avoid spicy spicy food. Avoid scratching the skin. Can heal in 4-6 weeks.

Vaccinia prevention

Due to the reform of modern milk extraction technology, manual operation is usually completely replaced by mechanization, so the number of cases of this disease is currently reduced, and this disease often occurs in workers in milking or slaughterhouses. Can also be caused by fake vaccinia virus infection. Therefore, immunization with vaccinia vaccine should be carried out to reduce the chance of infection of this disease. For cows suspected of being contaminated with vaccinia virus, gloves should be worn during milking to reduce the chance of infection.