Overview of porcine vesicular virus (SVDV)

Pathogenic characteristics

Pig blister (SVDV) belong to the small RNA viruses, enterovirus genera, spherical virus in electronic microscope, the average diameter of about 25.1 + / - 1.0 nm, icosahedron cubic symmetry, for single strand RNA genome, coefficient of precipitation is 150 + 3 s, the molecular weight of about 10.4 * 10 ^ 6. SVDV mainly exists in blister skin and blister fluid, viscera and muscle contains a minimal amount of virus, and has strong ability of resistance to acid alkali.

epidemic

Porcine blister occurs mainly in pig-farming regions of Europe and Asia, pigs of all ages and both sexes are susceptible, and outbreaks can occur all year round. No obvious seasonal epidemic of the disease, multiple in pig centralized place. Different varieties of different ages pigs are susceptible, spread generally no foot-and-mouth disease (FMD) fast, incidence of a disease also relatively low FMD.

Route of transmission

Transmitted mainly include direct contact with the transmission, through the digestive tract, respiratory tract, skin and mucosal infections. Virus can through contaminated feed, water, transportation, personnel, etc. Contact with sick pigs of cattle and sheep, although may not show symptoms, but also can detect the virus, mechanical transmission is possible.

clinical signs and symptoms

Clinical symptoms mainly for sick pigs feet, mouth, nose and sow a nipple a blister, causing the movement disorders. The incubation period is 2 to 6 days, and the incubation period for contact infection is 4 to 6 days. Early disease increased body temperature to 40.6 ℃ to 41.8 ℃, fever for 24 ~ 72 hours, then the coronet, hoof fork, hoof bottom or vice a blister, blister may rupture ulcer in 1 to 2 days. Part of sick pigs nose plate, oral cavity and around them will also be a blister.

Pathological changes

The pathological changes are mainly the formation of blisters, which start with a small area of skin turning white, then form a pale bulge, and expand with the formation of blisters. The epithelium separates from the basal layer, forming a red lesion with broken epithelial fragments. Lesions are usually waste pollution, leading to conditions bacteria secondary infection. Hoof lesions are often associated with cellulitis, persistent edema, and lameness.

Diagnostic methods

Diagnosis is difficult, because is similar to other diseases such as foot and mouth disease, swine blister stomatitis similar clinical symptoms, such as by laboratory diagnosis. The commonly used diagnostic methods include virus isolation and identification, fluorescent antibody test, neutralization test, reverse indirect hemagglutination test, etc. Laboratory diagnosis could detect serum antibody by ELISA method, and through the polymerase chain reaction (PCR) virus nucleic acid detection.

Prevention and control measures

Prevention measures include strict quarantine, isolation, blockade, innocent treatment of sick pigs and its products. Of the pig for emergency vaccination of the epidemic area and the threatened area, using effective disinfection disinfection medicine, and to ensure that biological safety in the process of introduction and dispatching. During the onset of the disease, symptomatic treatment includes the use of antibiotics to prevent secondary infections, and the washing and disinfection of the blister area. Traditional Chinese medicine treatment can also be used to prevent, such as cyrtomium rhizome powder, etc.

conclusion

To sum up, the pig blister virus (SVDV) is a main effect of pig's feet and oral acute infectious diseases, viruses with specific morphological characteristics, and are popular in different countries and regions. Its route of transmission diversity, clinical symptoms and pathological changes have certain characteristics, diagnostic methods involving multiple technology laboratory. Prevention and treatment need to be combined with the actual situation, should not only pay attention to the biological safety of individual pigs, also need to pay attention to public health security.