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Malignant Catarrhal Fever

Malignant Catarrhal Fever

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Malignant Catarrhal Fever

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  1. Malignant Catarrhal Fever Jeffrey Musser, DVM, PhD Professor Moritz van Vuuren Suzanne Burnham, DVM Texas A&M University University of Pretoria College of Veterinary Medicine Department of Veterinary Tropical Diseases Malignant Catarrhal Fever

  2. Notes For additional information, download this presentation and read the notes attached to each slide. Malignant Catarrhal Fever

  3. Malignant CatarrhalFever In this presentation the authors especially drew from the first hand experience of their colleagues in South Africa. Personal interviews as well as standard research sources provide the insights we bring you for the recognition of this exotic disease. Jeffrey Musser Suzanne Burnham Malignant Catarrhal Fever

  4. Malignant Catarrhal Fever Another word of thanks to Dr Corrie Brown who believes that sharing information will make the world a better place. Dr Brown generously has shared her work on this subject to add to the depth of this work. MALIGNANT CATARRHAL FEVER Dr Corrie Brown Malignant Catarrhal Fever

  5. Diseases Notifiable to the OIE • Cattle diseases Bovine anaplasmosisBovine babesiosisBovine genital campylobacteriosisBovine spongiform encephalopathy Bovine tuberculosisBovine viral diarrhoeaContagious bovine pleuropneumonia Enzootic bovine leukosisHaemorrhagic septicaemiaInfectious bovine rhinotracheitis/infectious    pustular vulvovaginitisLumpky skin diseaseMalignant catarrhal feverTheileriosisTrichomonosisTrypanosomosis (tsetse-transmitted) Malignant Catarrhal Fever

  6. Malignant Catarrhal Fever Malignant catarrhal fever, is an infectious disease of ruminants. It is also referred to as malignant catarrh, malignant head catarrh, and gangrenous coryza. In South Africa it may also be called “snotsiekte” which means “snotting sickness” Malignant Catarrhal Fever

  7. Malignant Catarrhal Fever Malignant catarrhal fever is a sporadic, usually fatal, pansystemic disease of cattle and deer characterized by low morbidity but high mortality, high fever, catarrhal inflammation of the upper respiratory tract and the digestive tract, dehydration, conjunctivitis, generalized lymphadenopathy and epithelial lesions. Malignant Catarrhal Fever

  8. Malignant Catarrhal FeverContents • Etiology • Host range • Transmission • Incubation • Clinical signs • Diagnosis • Differential Diagnosis Malignant Catarrhal Fever

  9. Etiology • Wildebeest derived MCF is caused by Alcelaphine herpesvirus type 1(AHV-1) • Sheep associated MCF is caused by Ovine herpesvirus-2 (OVH-2) Malignant Catarrhal Fever

  10. Etiology and • Caprine herpesvirus type 2 • All are Lymphotropic Cell-associated Gamma family herpesviruses Malignant Catarrhal Fever

  11. Etiology • Wildebeest-derived • Occurs wherever wildebeest live • Alcelaphine herpesvirus-1 • Sheep-associated • Endemic, worldwide; sheep is the natural reservoir host • Ovine herpesvirus-2 • Goat-derived • Goats are the natural reservoir host. • Caprine herpesvirus-2 • Seen in deer as alopecia, weight loss syndrome Malignant Catarrhal Fever

  12. Etiology All varieties of domestic sheep in North America are carriers of ovine herpesvirus-2 (OVH-2). Malignant Catarrhal fever in these natural hosts does not produce clinical disease. Likewise, goats are endemically infected with caprine herpesvirus-2 (CpHV-2) which apparently only causes clinical disease in deer. Malignant Catarrhal Fever

  13. Etiology The disease expression in “sheep-associated” MCF and “wildebeest-derived” MCF is very similar. Malignant Catarrhal Fever

  14. Host Range • The disease can occur in cattle, domesticated buffaloes, a wide range of captive antelopes and deer, and free-living deer. Malignant Catarrhal Fever

  15. Host Range • Under natural conditions only domestic cattle and deer develop clinical signs • MCF has never been reported in free-living wild animals in Africa Malignant Catarrhal Fever

  16. Host Range • In zoological collections a wide variety of ruminant species have been reported to develop clinical signs • Rabbits can be infected experimentally Malignant Catarrhal Fever

  17. Host Range • It was recently confirmed in pigs in Scandinavia Malignant Catarrhal Fever

  18. Reservoir ruminant species • Blue wildebeest • Black wildebeest • Domestic sheep • Goats Malignant Catarrhal Fever

  19. Blue Wildebeest Malignant Catarrhal Fever

  20. Black Wildebeest Malignant Catarrhal Fever

  21. Transmission Neonatal and adolescent wildebeest shed virus Malignant Catarrhal Fever

  22. Transmission from reservoir animals to domestic cattle, deer contact with calving wildebeest contact with lambing sheep Malignant Catarrhal Fever

  23. Cattle are more susceptible to Wildebeest derived MCF than to the sheep or goat MCF Malignant Catarrhal Fever

  24. Transmission • Transmission of the virus is associated with lambing time of sheep or calving season of wildebeest when the virus can be shed from nasal secretions. • After this period the virus occurs only as cell-associated, not free virus Malignant Catarrhal Fever

  25. Transmission • Droplets and aerosol dispersal of free virus may contaminate feed and water sources • Transmission to cattle mostly occurs by inhalation of droplets shed from ewes that are lambing Malignant Catarrhal Fever

  26. Natural transmission of the virus • Wildebeest to cattle  • Wildebeest to other ruminants  • Wildebeest to deer  • Sheep to cattle  • Sheep to other ruminants  • Sheep to deer  • Deer to susceptible species ? • Deer to deer  • Goats to susceptible species ? Quite likely • Cattle to cattle X Malignant Catarrhal Fever

  27. Congenital Transmission Cow will die then later calf will die Malignant Catarrhal Fever

  28. Pathogenesis Virus infects “natural killer” lymphocytes and transforms them. Transformed cells then replicate as if they were neoplastic and attack host. Terminal necrotizing lesions are believed to be the result of an autoimmune type phenomenon. Vessels and stratified squamous mucosal surfaces are attacked. Malignant Catarrhal Fever

  29. Incubation • Unknown for natural infections. Some animals are subclinically infected and only demonstrate symptoms when stressed. Some evidence indicates up to 200 days • Experimentally incubation periods may be from 7 to 77 days Malignant Catarrhal Fever

  30. Malignant Catarrhal Fever: Clinical Signs • In some cases MCF presents as chronic alopecia and weight loss as with deer infected with the Caprine herpesvirus. • However, MCF is typically fatal. Malignant Catarrhal Fever

  31. Clinical Signs • There are many factors that affect the duration of the disease in different species • The severity of the clinical symptoms will depend on those factors. Mortality is usually 100% but some animals face weeks of progressive disease • For this reasons, once the disease is identified, most elect to euthanized the affected animal. Malignant Catarrhal Fever

  32. Clinical Signs • High fever 106-107°F (41-41.5°C) • Depression • In deer - sudden death • Deer and bison that survive 2-3 days: • Hemorrhagic diarrhea • Bloody urine • Corneal opacity • Then death Malignant Catarrhal Fever

  33. Clinical Signs • The longer the animal survives the course of the disease the more severe the signs become. • For example, animals that die acutely may not develop lymphadenopathy or corneal opacity Malignant Catarrhal Fever

  34. As the disease progresses: • Catarrhal inflammation • Erosions and exudates in upper respiratory tract, ocular and oral mucosa • Swollen lymph nodes • Lameness • CNS signs (depression, tremors, stupor, hypo-responsive, aggression, convulsions Malignant Catarrhal Fever

  35. Clinical Signs • On average the time to death for European cattle is longer than for deer, bison and water buffalo; usually 7-17 days after the appearance of clinical signs • In cattle the swollen lymph nodes and severe eye lesions are more frequent Malignant Catarrhal Fever

  36. Clinical Signs • Hemorrhagic enteritis and cystitis are more frequently seen in bison and deer than in cattle • Skin lesions are common in animals that do not succumb quickly • Most eventually die, about 5% recover clinically Malignant Catarrhal Fever

  37. Clinical signs • Depressed and VERY SICK • Stertorous respiration • Enlarged lymph nodes Malignant Catarrhal Fever

  38. Clinical Signs Animals suffer, are painful and breathe with difficulty Malignant Catarrhal Fever

  39. Clinical Signs Secondary bacterial bronchopneumonia may be eventual cause of death if not euthanized first Malignant Catarrhal Fever

  40. Clinical Signs Painful swollen eyes Malignant Catarrhal Fever

  41. Clinical Signs Ocular and nasal discharge Malignant Catarrhal Fever

  42. Clinical Signs “snotsiekte” Malignant Catarrhal Fever

  43. Mucopurulent discharge, crusting occludes the nostril; animal begins open mouth breathing. Malignant Catarrhal Fever

  44. Malignant Catarrhal Fever

  45. Malignant Catarrhal Fever

  46. Characteristic of MCF Early corneal opacity begins at the limbus Progresses to total opacity Malignant Catarrhal Fever

  47. Clinical Signs Severe panophthalmitis, hypopion, corneal erosions are more frequent in cattle Malignant Catarrhal Fever

  48. Severe Ocular lesions Painful Conjunctivitis Malignant Catarrhal Fever

  49. Severe Ocular lesions Progresses to corneal opacity beginning at Limbus Malignant Catarrhal Fever

  50. Severe Ocular lesions Characteristic eye lesions Malignant Catarrhal Fever