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Foot and Mouth Disease. FMD, Aftosa. Overview. Organism Economic Impact Epidemiology Transmission Clinical Signs Diagnosis and Treatment Prevention and Control Actions to take. The Organism. Foot and Mouth Disease. Picornaviridae, Aphthovirus 7 distinct serotypes
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Foot and Mouth Disease FMD, Aftosa
Overview • Organism • Economic Impact • Epidemiology • Transmission • Clinical Signs • Diagnosis and Treatment • Prevention and Control • Actions to take Center for Food Security and Public Health Iowa State University - 2004
Foot and Mouth Disease • Picornaviridae, Aphthovirus • 7 distinct serotypes • Not cross protective • Affects cloven-hoofed animals • Inactivated at • pH below 6.5 and above 11 • Survives in milk, milk products, bone marrow, lymph glands Center for Food Security and Public Health Iowa State University - 2004
History • 1929: Last case in U.S. • 1953: Last cases in Canada and Mexico • 1993: Italy • 1997: Taiwan • 2001: United Kingdom • Other outbreaks in 1967-68 and 1981 Center for Food Security and Public Health Iowa State University - 2004
Direct costs Economic losses to farmers and producers Eradication costs Millions to billions of dollars lost Economically Devastating!! Indirect costs Exports shut down $3.1 billion in beef $1.3 billion in pork $14 billion in lost farm income $6.6 billion in livestock exports Consumer fear Economic Impact Center for Food Security and Public Health Iowa State University - 2004
Geographic Distribution Center for Food Security and Public Health Iowa State University - 2004
Foot and Mouth Disease Distribution 2003 Center for Food Security and Public Health Iowa State University - 2004
Morbidity/ Mortality • Morbidity 100% in susceptible animal population • United States, Canada, Mexico, others • Mortality less than 1% • Higher in young animals and highly virulent virus strains • Animals generally destroyed to prevent spread Center for Food Security and Public Health Iowa State University - 2004
Animal Transmission • Respiratory aerosols • Proper temperature and humidity • Survives 1-2 days in human respiratory tract • Direct contact • Ingestion of infected animal parts • AI, biologicals, hormones • Indirect contact via fomites Center for Food Security and Public Health Iowa State University - 2004
Animal Transmission Center for Food Security and Public Health Iowa State University - 2004
Human Transmission • Very rarely develop mild clinical signs • Type O, C, rarely A • Act as a transmitter to animals • Harbor virus in respiratory tract for 1-2 days • Contaminated boots, clothing, vehicles • Spread to susceptible animals • Ingestion of unprocessed milk or dairy products from infected animals Center for Food Security and Public Health Iowa State University - 2004
Clinical Signs • Incubation period: 2-12 days • Fever and vesicles • Feet, mouth, nares muzzle, teats • Progress to erosions • Abortion • Death in young animals • Recover in two weeks unless secondary infections arise Center for Food Security and Public Health Iowa State University - 2004
Clinical Signs in Cattle • Oral lesions • Vesicles on tongue, dental pad, gums, soft palate, nostrils, muzzle • Excess salivation, drooling, serous nasal discharge Center for Food Security and Public Health Iowa State University - 2004
Clinical Signs in Cattle • Teat lesions • Decreased milk production • Hoof lesions • Interdigital space • Coronary band • Lameness • Reluctant to move Center for Food Security and Public Health Iowa State University - 2004
Clinical Signs in Pigs • Hoof lesions • More severe than in cattle • Coronary band, heel, interdigital space • Lameness • Snout vesicles • Oral vesicles less common • Drooling is rare Center for Food Security and Public Health Iowa State University - 2004
Clinical Signs in Sheep and Goats • Mild, if any, signs • Fever • Oral lesions • Lameness • Makes diagnosis and prevention of spread difficult Fred Ward, USDA Larry Rana, USDA Center for Food Security and Public Health Iowa State University - 2004
Center for Food Security and Public Health Iowa State University - 2004
Post Mortem Lesions • Clinically indistinguishable from other vesicular diseases, especially swine • Single or multiple vesicles • Various stages of development • White area, 2mm-10cm • Fluid filled blister • Red erosion, fibrin coating • Dry lesions • Tiger heart Center for Food Security and Public Health Iowa State University - 2004
Differential Diagnosis • In swine • Vesicular stomatitis • Swine vesicular disease • Vesicular exanthema of swine • Foot rot • Chemical and thermal burns • In cattle • Rinderpest, IBR, BVD, MCF, Bluetongue Center for Food Security and Public Health Iowa State University - 2004
Sampling • 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 Center for Food Security and Public Health Iowa State University - 2004
Clinical Diagnosis • Clinically vesicular diseases are indistinguishable • Salivation, lameness with vesicles requires further testing • Tranquilization may be necessary Center for Food Security and Public Health Iowa State University - 2004
Diagnosis • Laboratory Tests • Initial diagnosis • Virus isolation and identification • Antigen or nucleic acid detection • Complement fixation • ELISA and virus neutralization • Notify authorities and wait for instructions before collecting samples Center for Food Security and Public Health Iowa State University - 2004
Treatment • No treatment available • Supportive care to those afflicted • U.S. outbreak could result in • Quarantine • Euthanization • Disposal • Vaccine available • Ramifications are many and discussed later Center for Food Security and Public Health Iowa State University - 2004
Human Clinical Signs • Very low incidence of human disease • 40 cases since 1921 • Most reports ended when FMD was eradicated in Europe • Incubation period: 2-6 days • Clinical signs • Mild headache, malaise, fever • Tingling, burning sensation of fingers, palms, feet prior to vesicle formation Center for Food Security and Public Health Iowa State University - 2004
Human Clinical Signs • Vesicles 2 mm to 2 cm in diameter • Fluid-filled • Oral blisters on tongue, palate • Painful • Interfere in eating, drinking, talking • Diarrhea • Vesicles dry up in 2-3 days • Recover within a week of last blister appearing Center for Food Security and Public Health Iowa State University - 2004
Diagnosis and Treatment • Clinically FMD in humans resembles • Coxsackie A group viruses • Hand, foot and mouth disease • Herpangina • Herpes simplex virus • Primary herpetic gingivostomatitis • Vesicular stomatitis • Virus isolation or antibody identification required for diagnosis • Treatment is supportive care Hand, Foot & Mouth Disease Center for Food Security and Public Health Iowa State University - 2004
Public Health Significance • FMD in humans is not a public health concern • 40 cases since 1921 documented in humans • Europe, Africa, South America Center for Food Security and Public Health Iowa State University - 2004
Prevention • USDA APHIS: Strict import restrictions • Prohibit live ruminants, swine, and their products from FMD-affected countries • Monitor travelers and belongings at ports of entry • 450 FADD to investigate suspicious lesions • State planning/training exercises • Biosecurity protocols for livestock facilities Center for Food Security and Public Health Iowa State University - 2004
Recommended Actions • Notification of Authorities • Federal: Area Veterinarian in Charge (AVIC) www.aphis.usda.gov/vs/area_offices.htm • State veterinarian www.aphis.usda.gov/vs/sregs/official.html • Quarantine Center for Food Security and Public Health Iowa State University - 2004
Recommended Actions • Confirmatory diagnosis • Depopulation may occur • Proper destruction of exposed cadavers, litter, animal products Center for Food Security and Public Health Iowa State University - 2004
Disinfection • Effective solutions include • 2% sodium hydroxide (lye) • 4% sodium carbonate (soda ash) • 5.25% sodium hypochlorite (household bleach) • 0.2% citric acid • Areas must be free of organic matter Center for Food Security and Public Health Iowa State University - 2004
Vaccination • Killed vaccine, serotype specific • North American Foot-and-Mouth Vaccine Bank • Plum Island, NY • Monitor disease outbreaks worldwide and stock active serotypes and strains • It is essential to isolate virus and identify the serotype to select the correct vaccine Center for Food Security and Public Health Iowa State University - 2004
Vaccination • U.S. has no need to vaccinate • Have not had animals affected since 1929 • May be used to control an outbreak • Huge implications if we do vaccinate • Annual re-vaccination required • Costly, time consuming • Does not protect against infection, just clinical signs • Spread infection to other animals • International trade status harmed Center for Food Security and Public Health Iowa State University - 2004
Resources • World Organization for Animal Health (OIE) website • www.oie.int • USDA APHIS Veterinary Services • www.aphis.usda.gov/vs • 1-866-SAFGUARD is a toll-free hotline with recorded messages for international travelers Center for Food Security and Public Health Iowa State University - 2004
Development of this presentation was funded by a grant from the Centers for Disease Control and Prevention to the Center for Food Security and Public Health at Iowa State University. Acknowledgments
Acknowledgments Author: Co-authors: Reviewer: Danelle Bickett-Weddle, DVM Anna Rovid Spickler, DVM, PhD Kristina August, DVM James Roth, DVM, PhD Bindy Comito Sornsin, BA