Swine Vesicular Exanthema

Swine Vesicular Exanthema : 

Swine Vesicular Exanthema SUBMITTED BY P.MAHALINGAM BVM06066

Swine Vesicular Exanthema : 

8/3/2009 2 Maha Swine Vesicular Exanthema DEFINITION: An acute, contagious disease of Swine characterized by vesicles on snout, lips, nostrils, tongue, feet and mammary glands and very similar to FMD. General characters: Classification: Baltimore Group IV Family: Caliciviridae Genus : Vesivirus Species: Swine vesicular exanthema virus Synonyms: Miguel Sea Lion Virus (SMSV) ,VESV

General characters : 

8/3/2009 3 Maha General characters Morphology: Positive-sense, (+) Single stranded RNA Non-segmented. Non enveloped Capsid has a diameter of 35-39 nm. 5'-end of the genome has a genome-linked protein (VP g). 3'-terminus has a poly (A) tract. Complete genome is 7900 nucleotides long. viral genome encodes structural proteins. Lipids are not reported.

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8/3/2009 5 Maha Risk group: Not transmissible to humans. Resistance: Survive at 60º C for 1 hour. Also resist to Ether, Chloroform, Deoxycholate but inactivated by 2% NaOH. Inactivated in pH about 3-5. Replication: Cytoplasmic Serotypes: 13 serotypes like VESV-B1-34(strain aka 1934B), A48, B51. Transmission: Direct contact and feeding infected uncooked pork scraps Lesions: Epithelial lesions are identical to the other vesicular diseases.  No systemic lesions

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8/3/2009 6 Maha Incubation period: 2–4 days Symptoms: Large number of hogs are affected. Heavy mortality in suckling pigs Blotchy rash in unpigmented skin (exanthema) Vesicles on the snout and in the mouth. Ruptured vesicles result in erosions Loss of weight Walking on their knees and lameness Squealing when forced to move

Walking on knees due to pain from the vesicular lesion on the feet. : 

8/3/2009 7 Maha Walking on knees due to pain from the vesicular lesion on the feet.

Vesicles on the snout and in the mouth. Ruptured vesicles result in erosions : 

8/3/2009 8 Maha Vesicles on the snout and in the mouth. Ruptured vesicles result in erosions

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8/3/2009 9 Maha Clinical Signs:  Fever up to 107oF.  Vesicles are found on the epithelium of the snout, lips, nostrils, tongue, feet and mammary glands.  Very similar to FMD  Isolation and serotyping: Using primary swine kidney culture, and also lungs, liver, etc.., Identified as serotype B51 using complement fixation and serum neutralization tests

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8/3/2009 10 Maha Presumptive diagnosis: Based on fever and the presence of typical vesicles, which break within 24-48 hr to form erosions. Diagnosis: Based on the complement-fixation tests, ELISA, Electron microscopy on epithelial tissue, or After passage in swine tissue cultures. Serum neutralization tests Immuno-electron microscopy Reverse transcriptase-PCR(RT-PCR). Treatment and Control:  Slaughter and disposal of infected and contact animals and disinfection of the premises.

References : 

8/3/2009 11 Maha References http://www.ncbi.nlm.nih.gov/ICTVdb/ICTVdB/index.htm http://en.wikipedia.org/wiki/RNA_virus#Single-stranded_RNA_viruses_and_RNA_Sense www.thepigsite.com/.../vesicular-exanthema-of-swine-ves Principles of bacteriology, virology and Immunity by Sir Graham S Wilson and Sir Ashley. Introduction of modern virology by N.J.Dimmock Veterinary Bacteriology and Virology by I.A. Merchant and R.A. Packer.