Malignant Catarrhal Fever Investigation Dr. Leonard E. Eldridge State Veterinarian Dr. Paul Kohrs Assistant State Veterinarian Dr. Jerry Pospisil Field Veterinarian WSDA
Topics for today • In-state movement • WSDA’s role in disease outbreaks • Pathogenic strains and their hosts • MCF characteristics • Timeline of Puyallup cases • What we know so far • Prevention or mitigation of risk
Duties of State Veterinarian • Set protective requirements for animals entering the state • Investigate reports of animals not meeting state requirements • Investigate and trace reports of exposed and sick animals • Identify, control, and eliminate select animal diseases • Includes zoonotic diseases (animal diseases that spread to humans)
Stevens Ferry Whatcom Okanogan Pend Oreille San Juan VET Region 1 Dr. Jeff Howlett Skagit VET Region 4 Dr. Ben Smith Island Clallam Snohomish Chelan Douglas Kitsap Jefferson Lincoln King Mason Spokane Grays Harbor Grant VET Region 2 Dr. Jerry Pospisil Whitman Kittitas Adams Pierce Thurston Yakima Lewis Pacific Garfield Franklin VET Region 3 Dr. Peter Tran Columbia Wahkiakum Cowlitz Skamania Walla Walla Benton Asotin Klickitat Clark Field Veterinarian Regions
Animal Health Requirements • Importation into state • Entry permit • Certificate of veterinary inspection • Female cattle vaccinated for brucellosis • Negative test for brucellosis on all cattle where there is risk • Negative test for tuberculosis • Negative Trichomoniasis test or virgin bull statement • Official individual animal identification • Canada • CAN brand • Mexico • M brand • Movement within the state
WSDA’S Role in Disease Outbreaks • Respond to private practitioner concerns • Any vesicular disease should be reported • Other possible FAD’s should be reported • Respond within 4 hours with FADD • Either facilitate sample collection and submission or personally collect and send samples • Place movement restrictions on animals if deemed appropriate • Rule out FAD with confirmation of lab results • Non-FAD or program disease will be turned over to private practitioner
Role of the Animal Health OfficialDuring a Disease Outbreak • Stop Disease Spread • Quarantine and Movement Restrictions • Trace Infected and Exposed Animals • Trace In: All animals entering infected premises • Trace Out: All animals leaving infected premises • Implement Disease Control Measures • Humane euthanasia and disposal • Cleaning and disinfection • Animal disease inspection and investigation ALL Require Livestock Traceability
$ Impact of Losing “Disease-Free” status • Loss of Free Status for TB or Brucellosis cost: • 10 cents per pound ($50 on 500-pound calf) • $8 to $10 per head (each time cattle are tested) • $5 to $55 million (in added costs to state) • Indemnity value may be lower than animal is worth
Transporting cattle within WA State • Proof of ownership documents are required while transporting cattle on public highways. • Brand Inspection Certificate • Public Livestock Market (PLM) – “out slip” • Buyers are issued an “out slip” for cattle purchased from a livestock market or special sale • Certificate of Permit - “haul slip” is your permit for transporting cattle on public highways Brand Inspections are also required when cattle leave Washington State
History • MCF in wildebeests in Africa for centuries • U.S. cattle since 1920’s • First bison case in South Dakota reported in 1973 • Cases occur worldwide each year • 2002: New Jersey exotic theme park • AHV-1 diagnosed in Ankoli cattle • May 2008 outbreak in Texas
Malignant Catarrhal Fever (MCF) Virus Characteristics • Herpes virus • 10 identified strains- 5 strains have been identified as causing disease • Highly adaptive to the carrier host (they seldom, if ever, show signs of the disease) • Grows very poorly in cell cultures • Cannot make vaccine • Makes typing the virus difficult • DNA virus, so the virus is quite stable against mutation • Affects even-toed ungulates
Geographic Distribution • AHV-1 primarily in Africa • Carried by wildebeest, hartebeest, topi • Also in zoologic and wild animal parks • OHV-2 worldwide • Carried by domestic and wild sheep and goats
Geographic Distribution • Positive bison have been found in North America (11 states and Canada) • Bison very susceptible • Idaho outbreak • Spokane outbreak • Lost 12/50 animals • Used TSV2 with some effect?? • Neighbor ½ mile downwind also lost 2 (cattle) animals consistent with MCF • Often misdiagnosed in bison
Transmission • Nose-to-nose contact with sheep is the most efficient method of spread • Fomite transmission is well documented • Adolescent age lambs shed higher numbers of the virus • Seems to peak in late summer or fall when a majority of the lamb crop is 6-9 months old
Incubation period • Average 40-60 days • The virus may become latent in infected animals and the disease may appear as long as 20 months later • The virus is not very stable outside the host and will only live a few hours without moisture and organic matter
Human Transmission • MCF has not been documented as causing disease in humans • Caution at lambing time • Equipment used could spread infection to susceptible animals • Virus quickly inactivated by sunlight • Minimizes risk of fomite spread
MCF Characteristics • Cattle are “dead end” hosts for the Ovine strain. • No documented spread from infected cattle to other cattle • High mortality in symptomatic cases. • Low morbidity - typically very few animals become symptomatic Plum Island Animal Disease Center (PIADC) Photo by Fakri Fatima Zohra, WikiMedia
Head and Eye Form- Early stages • Reddened eyelids • Bilateral corneal opacity • Crusty muzzle, nares • Nasal discharge • Salivation
Head and Eye Form- Later stages • Erosions on the tongue • Erosions on the buccal mucosa
BVD mucosal disease Bluetongue Rinderpest FMD Vesicular stomatitis Physical injury Salmonellosis Pneumonia complex Oral exposure to caustic materials Mycotoxins Poisonous plants Differential Diagnosis
Treatment • Survival is rare • Mortality on clinical animals reaches 100% • Supportive therapy, antibiotics for secondary bacterial infection
MCF Outbreak at Puyallup Fair • Animals were housed in the same barn for the last 5 days of the fair (Sept 17-21) • 133 cattle in the barn (FFA, open class and display cows) • Considerable concern regarding the “animals of the world display” (most were susceptible species)
Timeline • November 3rd - 43 days after the last day of the fair- the first case occurred in Lynden, WA. The animal died on Nov 6th and was necropsied and samples were submitted to WADDL • Diagnosis of MCF confirmed on Nov 10th. • Reported to State Veterinarian’s office Nov 11th • An animal in Arlington, WA that had been at the fair died and was sampled Nov. 11th and confirmed MCF positive on Nov. 14th. • First meeting with Fair Officials on Nov. 14th.
Timeline • The next week (17th-21 of Nov) • Second and third animals at Arlington died • Another display cow housed with the first unconfirmed case earlier was confirmed positive • Calf from the positive cow in Elma died and was confirmed positive • More positive cases at the index farm in Lynden (total of five with 4 confirmed) • Another display cow from Sequim is confirmed as well • Negative to Foreign Animal Disease on Nov. 19th. • Meeting with Fair Officials on Nov. 19th
Timeline • That weekend (Nov 22-23), more cases were reported in Fife, Elma and ‘display cows’ were reported dying with MCF symptoms in Lynden and Yelm. Though not confirmed, these cases were highly suspicious. • The veterinarians that examined the animals became very good at recognizing positive cases.
Timeline • Week of Nov 24-28 • 2 display animals showed MCF symptoms located in Buckley. One animal died and confirmed MCF, second animal recovered - not MCF. • One animal from the Napavine area died showing MCF symptoms, later confirmed MCF. • A sixth animal at the index farm in Lynden died on Monday Dec 1st confirmed MCF.
Timeline • Animal reported dead with MCF symptoms on December 6th from Castle Rock- not confirmed. • Second animal from Castle Rock farm died on December 28th and confirmed positive. • Animal in Olalla showed symptoms for nearly 30 days before dying on January 4th, confirmed positive.
Timeline • Update Case numbers • 19 confirmed MCF • 5 probable suspicious deaths • Last reported case Feb 7th
Timeline • Summary of the Veterinarian Interviews on cases of MCF • Case information was obtained by interview for 24 head of cattle. The affected cattle were 22 months of age on average with a range of 5 to 60 months. • Many breeds were represented and included beef and dairy animals: • 4Herefords, 3 Guernseys, 3 Holsteins, 2 Brown Swiss, 1 Jersey, 2 Simmental cross 1crossbred, 7 Angus and 1Milking Shorthorn • The dates of death by week showed that the peak occurred in the week of November 11th; 9 weeks after showing at the fair
What we know • This outbreak occurred at the Puyallup Fair, but it could happen anywhere animals (sheep and cattle) are commingled • Every one of the cases that were confirmed were cattle exhibited at the Puyallup Fair • Foreign Animal Diseases were ruled out with Plum Island testing
What we know so far • The weather (humidity 80-100% for the whole event), age of the sheep, time of year, and ventilation patterns may have combined to produce the “Perfect Storm” for this disease to be transmitted • Stress
The Perfect Storm • This event will change the way fairs do business for a long time to come. • This is a wake-up call for everyone; not just fairs and regulatory personnel, EVERYONE NEEDS TO BE ALERT. This could have just as easily been Foot and Mouth Disease. • Officials say its not if but when we experience a FAD
Notification • The Puyallup Fair sent a letter to open class exhibitors and communicated with FFA and 4H chapter advisors. • Bovine Issues Working Group • WSDA sent a letter to all large animal practitioners in the state. • WSDA sent a letter to all bovine and ovine producers who had a registered state premises. • WSDA contacted WDF, WCA, CPOW and Feeders
Laboratory Testing • WSDA and WSU paid for preliminary testing until confirmed diagnosis • USDA Agriculture Research Service is paying for all follow up MCF testing • Washington FFA Foundation, P.O. Box 14633, Tumwater, WA 98511. • Note: donation is for MCF fund
Biosecurity • For some diseases, the risk for transmission is greater through one route over another. However, having all the prevention steps in place will reduce the risks for a number of diseases at the same time • Although mentioned as a potential fomite, the role that people play in disease transmission cannot be emphasized enough. People wear the boots, touch the animals, and use the equipment
Biosecurity 101 • Co-mingled animals at any collection point are a risk • Separate infected and carrier animals from susceptible species. • Assume sheep are carriers • Goats maybe sporadic • Biosecurity • Species dedicated clothing and equipment • Wash hands before and after handling animals • Common sense, foot baths, insect control and education
Prevention and Control • Avoid exposing cattle, bison and deer during parturition. • Zoological parks: Introduce only sero negative animals • No vaccine available • Possible value in intranasal vaccines with interferon production?
Take Home Messages • Don’t mix species at any collection point • Call quickly with suspicious disease symptoms • Rule out FAD • More rapid containment • MCF may not be as rare as we thought it was-prevention is the key • Communication is key to rapid containment