Musser JMB Diseases in Nature ORF: A Shared Vesicular Disease of Sheep, Goats, and Humans Jeffrey MB Musser and Susan L Payne Department of Veterinary Pathobiology College of Veterinary Medicine Texas A&M University Texas A&M University
Musser JMB Diseases in Nature Sheep feeder – well developed vesicles on right hand lesser number of vesicles on left hand lesser number of vesicles on left hand Case 1
Musser JMB Diseases in Nature Inoculate sheep with vesicle fluid Day 5 – reddening of the scratched area Day 6 – pustules Case 1 Day 11 – max pustule development Becomes scabs, dry up, and drop off
Musser JMB Diseases in Nature First reported case in U.S. of sore mouth (orf) as a zoonotic disease Case 1 Newsom IE and Cross F. Sore mouth in sheep transmissible to man. JAVMA 1934.
Musser JMB Diseases in Nature Presentation Outline 1. Parapox virus overview 2. Contagious ecthyma in sheep and goats 3. Orf in humans 4. Transmission and Risk factors 5. Diseases w/ similar presentations 6. Diagnosis 7. Prevention 8. Conclusion
Musser JMB Diseases in Nature Parapox virus overview Poxviridae (subclass chordopoxviridae) Cowpox (cats, cows, rodents, and humans) Smallpox (humans) Monkeypox (monkeys, rodents, rabbits, and humans) Orthopoxvirus Molluscum contagiosum (humans) Parapoxvirus Contagious ecthyma or Orf (sheep, goats, and humans) Molluscipoxvirus Pseudocowpox (cows and humans) CapripoxvirusGoatpox (goats and humans; most likely not zoonotic) characterized by generalized or localized cutaneous lesions
Musser JMB Diseases in Nature Parapox virus overview Parapox virus - endemic in major sheep and goat rearing areas of the United States, such as the Hill Country and West Texas Source: USDA 2007 Census of Agriculture
Musser JMB Diseases in Nature Lesions - sheep and goats Texas AgriLIFE, Sonora
Musser JMB Diseases in Nature Other lesion locations Teats and perianal region Texas AgriLIFE, Sonora
Musser JMB Diseases in Nature Virulent form Texas AgriLIFE, Sonora
Musser JMB Diseases in Nature Clinical presentation - humans Source SCP-ASIM Bioterrorism resource Center CDC 2006.
Musser JMB Diseases in Nature Clinical presentation - humans Source: Buttner M
Musser JMB Diseases in Nature Clinical presentation - humans Source: Al-Salam s Source: Lederman 2007
Musser JMB Diseases in Nature Clinical presentation - humans Source: Georgiades G
Musser JMB Diseases in Nature Transmission Damage to skin or mucosa allows the virus to infect and replicate in regenerating epidermal cells
Musser JMB Diseases in Nature Transmission Risk Factors Direct contact with sheep or goats Time of year (season) Use of vaccine Bottle feeding and caring for ill animals Not wearing gloves
Musser JMB Diseases in Nature Transmission Petting zoos 4- H Projects La Graciosa 4-H Market Goat Project
Musser JMB Diseases in Nature Diseases w/ similar presentation Orf can be clinically confused with other Poxvirus infections and other cutaneous disease such as: cutaneous anthrax tularemia cutaneous leishmaniasis monkey pox erysipeloid pseudocowpox (milkers nodules) ecthyma
Musser JMB Diseases in Nature Diseases w/ similar presentation Orf lesion Contact with sheep or goats Lesion primarily on the dorsal fingers Lesion associated with crusts and scabbing Cutaneous anthrax Characteristic non-pitting edema surrounding ulcer and eschar Lesion is not limited to fingers Ulcer is painless Source: ACP-ASIM Bioterrorism Resource Center
Musser JMB Diseases in Nature Diseases w/ similar presentation Tularemia Contact with cats, rabbits, foxes, squirrels, muskrats, beavers, and pheasants or potential exposure to tick or deer fly vector Lesion is painful papule or ulcer Source: NABC. Kansas State University Orf lesion Contact with sheep or goats Lesion primarily on the dorsal fingers Lesion associated with crusts and scabbing
Musser JMB Diseases in Nature Diseases w/ similar presentation Cutaneous Leishmaniasis Patient has traveled to or resides in an endemic area Lesion slowly evolves from papule to ulcer Nodular lymphangitis may be present Source: ACP-ASIM Bioterrorism Resource Center Orf lesion Contact with sheep or goats Lesion primarily on the dorsal fingers Lesion associated with crusts and scabbing
Musser JMB Diseases in Nature Diseases w/ similar presentation Monkey pox Contact with monkeys, rodents, and rabbits Fever, headache, myalgia, exhaustion, (flu like) Lymph nodes usually enlarged Orf lesion Contact with sheep or goats Lesion primarily on the dorsal fingers Lesion associated with crusts and scabbing Source Davis R.G. CRSPH, Iowa State University
Musser JMB Diseases in Nature Diagnostics Clinical signs and History Histopathology Electron microscopy Serology rtPCR - amplification of a 70 bp fragment from the ORFV B2L gene that encodes the major envelope protein. 100 nm Image by Ross Payne, VTPB,CVM,TAMU
Musser JMB Diseases in Nature Prevention Knowledge Proper hand hygiene DisinfectionGloves
Musser JMB Diseases in Nature Conclusion a self-limiting condition easily recognized by people at risk who do not always seek medical care physicians may be unfamiliar with disease and clinical signs true prevalence of human orf infection likely underestimated Source: Buttner M
Musser JMB Diseases in Nature Good resources Texas Department of State Health Services ACP-ASIM Bioterrorism Resource Center USDA and CDC faq: Frequently Asked Questions About Sore Mouth (orf virus) About Sore Mouth (orf virus) Center for Food Security & Public Health (Iowa State University)
Musser JMB Diseases in Nature The Entry of the Animals into Noah's Ark Jan Brueghel the Elder, 1613 Questions?