290 likes | 997 Views
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 . Case 1. Sheep feeder – well developed vesicles on right hand
E N D
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
Case 1 Sheep feeder – well developed vesicles on right hand lesser number of vesicles on left hand
Case 1 Inoculate sheep with vesicle fluid Day 5 – reddening of the scratched area Day 6 – pustules Day 11 – max pustule development Becomes scabs, dry up, and drop off
Case 1 First reported case in U.S. of sore mouth (orf) as a zoonotic disease Newsom IE and Cross F. Sore mouth in sheep transmissible to man. JAVMA 1934.
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
Parapox virus overview Poxviridae (subclass chordopoxviridae) Smallpox (humans) Orthopoxvirus Cowpox (cats, cows, rodents, and humans) Monkeypox (monkeys, rodents, rabbits, and humans) Contagious ecthyma or Orf (sheep, goats, and humans) Parapoxvirus Pseudocowpox (cows and humans) Molluscipoxvirus Molluscum contagiosum (humans) Capripoxvirus Goatpox (goats and humans; most likely not zoonotic) characterized by generalized or localized cutaneous lesions
Source: USDA 2007 Census of Agriculture 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
Texas AgriLIFE, Sonora Lesions - sheep and goats
Texas AgriLIFE, Sonora Other lesion locations Teats and perianal region
Texas AgriLIFE, Sonora Texas AgriLIFE, Sonora Texas AgriLIFE, Sonora Virulent form
CDC 2006. Source SCP-ASIM Bioterrorism resource Center Clinical presentation - humans
http://www.cdc.govl Clinical presentation - humans Source: Buttner M. 2002.
Clinical presentation - humans Source: Al-Salam s. 2007 Source: Lederman 2007
Source: Georgiades G. 2005. Source: Georgiades G. 2005. Clinical presentation - humans Source: Georgiades G. 2005.
Transmission Damage to skin or mucosa allows the virus to infect and replicate in regenerating epidermal cells
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
4- H Projects Petting zoos www.motmplus.com La Graciosa 4-H Market Goat Project Transmission
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 (milker’s nodules) ecthyma
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 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 Diseases w/ similar presentation Orf lesion Contact with sheep or goats Lesion primarily on the dorsal fingers Lesion associated with crusts and scabbing
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 Diseases w/ similar presentation Orf lesion Contact with sheep or goats Lesion primarily on the dorsal fingers Lesion associated with crusts and scabbing
Monkey pox Contact with monkeys, rodents, and rabbits Fever, headache, myalgia, exhaustion, (flu like) Lymph nodes usually enlarged Source Davis R.G. CRSPH, Iowa State University Source Davis R.G. CRSPH, Iowa State University Diseases w/ similar presentation Orf lesion Contact with sheep or goats Lesion primarily on the dorsal fingers Lesion associated with crusts and scabbing
100 nm Image by Ross Payne, VTPB,CVM,TAMU 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.
Prevention Knowledge Proper hand hygiene Disinfection Gloves
Source: Buttner M. 2002. Conclusion true prevalence of human orf infection likely underestimated 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
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) Center for Food Security & Public Health (Iowa State University)
Questions? The Entry of the Animals into Noah's ArkJan Brueghel the Elder, 1613