Organism Organism Economic Impact
tarix 26.11.2016 ölçüsü 458 b. #212
Organism Organism Economic Impact Epidemiology Transmission Clinical Signs Prevention and Control Actions to Take
RNA Vesiculovirus RNA Vesiculovirus Family Rhabdoviridae Major serotypes Affects horses, cattle, swine, camelids, humans Sheep and goats resistant Closely resembles exotic vesicular diseases including FMD
Early 1800s Early 1800s Horse illness resembling VSV 1927: Virus identified 1950s: Human infections recorded 1982-83: Outbreak in western U.S.
1998-99: NM, CO, TX; 130 positives 1998-99: NM, CO, TX; 130 positives 2004-05: TX, NM, CO; 470 positives 2005: Nine states; 786 positives 2006: WY; 29 positives 2009: TX, NM; 7 positives 2010: AZ; 4 positives
1928: California dairy herds 1928: California dairy herds 1995: New Mexico beef herd Losses due to: Increased culling, increased mortality Reduced milk production Labor, medicine, veterinary costs
Western hemisphere Western hemisphere North, Central, and South America Emergence in eastern hemisphere? 2009: Bahrain, Laos (suspected) 2009: Pakistan (limited regions) Southwest U.S. Outbreaks in warmer regions Southeast U.S.: enzootic cycle
Morbidity Morbidity Range: 5 to 90% Most animals seroconvert Mortality Higher in adults Death rare in cattle and horses
Vectors Vectors Direct contact Infected animals Contaminated objects
Direct contact Direct contact Infected tissues, vesicular fluid, saliva Insect bites Aerosol
Incubation period Incubation period Fever and vesicles that resemble FMD Horses severely affected Oral lesions Drooling, chomping, mouth rubbing, lameness Coronary band lesions
Cattle, pigs Cattle, pigs Vesicular lesions Oral, mammary gland, coronary band, interdigital region Usually isolated to one body area Salivation, lameness Recover within 2 weeks
Gross lesions Gross lesions Histopathology Degeneration of epithelial cells
Before collecting or sending any samples, the proper authorities should be contacted Before collecting or sending any samples, the proper authorities should be contacted Samples should only be sent under secure conditions and to authorized laboratories to prevent the spread of the disease
Vesicular diseases are clinically indistinguishable! Vesicular diseases are clinically indistinguishable! But, symptoms in horses are suggestive VSV vs. FMD VSV less contagious VSV lesions generally found in one area of the body
Virus isolation Viral antigen detection Vesicular fluid or epithelium ELISA, complement fixation, virus neutralization Antibody tests Paired serum samples ELISA, complement fixation, virus neutralization
No specific treatment available No specific treatment available Supportive care Fresh, clean water Electrolytes if necessary Soft feeds Good prognosis Production animals may suffer losses
Incubation period: 1 to 6 days Incubation period: 1 to 6 days Influenza-like symptoms Headache, fever, retrobulbar pain, malaise, nausea, limb and back pain, oral vesicles (rare) Self-limiting disease, supportive care Recovery can be prolonged Death is rare
Clinical diagnosis difficult Clinical diagnosis difficult Flu-like illness Many do not seek treatment Differentials include: Coxsackie A group viruses (Hand, foot and mouth disease) Herpes simplex Diagnosis via serology
Low incidence of human illness Chance of infection when handling contaminated tissues Biosafety level 3 Personal protective equipment Rarely causes vesicle formation Recover in 4 to 7 days
IMMEDIATELY notify authorities IMMEDIATELY notify authorities Federal Area Veterinarian in Charge (AVIC) http://www.aphis.usda.gov/animal_health/area_offices/ State State veterinarian http://www.usaha.org/StateAnimalHealthOfficials.pdf Quarantine
Easily inactivated Easily inactivated Area must be free of organic matter Contact time of at least 10 minutes Disinfectants Phenolic, halogen-based disinfectants Soda ash, 2% iodophores Chlorine dioxide, 1% chlorine bleach 1% cresylic acid Quaternary ammonium
Vaccines used in some endemic regions of Central, South America Vaccines used in some endemic regions of Central, South America Vaccines may be available during an outbreak Contact state veterinarian for availability information
Do not buy from positive herds for 3 months post-infection Do not buy from positive herds for 3 months post-infection Avoid grazing at peak insect feeding hours Sanitation Insect control programs
World Organization for Animal Health (OIE) World Organization for Animal Health (OIE) U.S. Department of Agriculture (USDA) Center for Food Security and Public Health USAHA Foreign Animal Diseases (“The Gray Book”) www.usaha.org/pubs/fad.pdf
Development of this presentation was funded by grants from Development of this presentation was funded by grants from the Centers for Disease Control and Prevention, the Iowa Homeland Security and Emergency Management Division, and the Iowa Department of Agriculture and Land Stewardship to the Center for Food Security and Public Health at Iowa State University. Authors: Danelle Bickett-Weddle, DVM; Anna Rovid Spickler, DVM, PhD; Kristina August, DVM; James A. Roth, DVM, PhD Reviewers: Bindy Comito Sornsin, BA; Kerry Leedom Larson, DVM, MPH, PhD
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