Malignant Catarrhal Fever Symptoms 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

Malignant Catarrhal Fever 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

Malignant Catarrhal Fever 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

Malignant Catarrhal Fever 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

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

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

Malignant Catarrhal Fever Blue Wildebeest Malignant Catarrhal Fever

Malignant Catarrhal Fever South Africa is the only natural habitat of the black wildebeest. The populations were nearly decimated by hunters but have recently increased in number. Prof. Moritz van Vuuren Black Wildebeest Malignant Catarrhal Fever

Transmission Neonatal and adolescent wildebeest shed virus www.africadreamsafaris.com/.../serengeti.html Malignant Catarrhal Fever

Transmission from reservoir animals to domestic cattle, deer contact with calving wildebeest contact with lambing sheep Primarily the virus is cell associated. Cell-free virus is shed in nasal secretions by neonatal and adolescent sheep. Neonatal wildebeest may shed cell-free virus in lacrimal and nasal secretions and in feces up to 4 months of age. Malignant Catarrhal Fever

Malignant Catarrhal Fever Cattle are more susceptible to Wildebeest derived MCF than to the sheep or goat MCF www.bayhavenfarm.com/corriedale_sheep.htm Bay Haven Farm Cleveland Bay Horses www.africadreamsafaris.com/.../serengeti.html Africa Dreams Safais: the Serengeti National Park Malignant Catarrhal Fever

Congenital Transmission Cow will die then later calf will die Because the virus is usually intracellular there is no cow to cow transmission. Cattle are considered the dead end host. Malignant Catarrhal Fever

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

Malignant Catarrhal Fever 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

Malignant Catarrhal Fever 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

Malignant Catarrhal Fever 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

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

Malignant Catarrhal Fever 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

Malignant Catarrhal Fever 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

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

Malignant Catarrhal Fever Clinical Signs Present with extended head, stertorous breathing, and lesions in the oral mucosa. Also notice the encrustation around the muzzle. MvV Animals suffer, are painful and cannot breathe well Malignant Catarrhal Fever

Malignant Catarrhal Fever Clinical Signs Secondary bacterial bronchopneumonia may be eventual cause of death if not euthanized first. Animals suffer, are painful and cannot breathe well. Euthanasia is usually recommended. Mvv Secondary bacterial bronchopneumonia may be eventual cause of death if not euthanized first Malignant Catarrhal Fever

Malignant Catarrhal Fever Clinical Signs Cattle stand with neck stretched out and eyes closed due to painful ophthalmia. This cow also has a nasal discharge. MvV Painful swollen eyes Malignant Catarrhal Fever

Malignant Catarrhal Fever Clinical Signs Ocular and nasal discharge cb Malignant Catarrhal Fever

Malignant Catarrhal Fever Clinical Signs cb “snotsiekte” Malignant Catarrhal Fever

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

Malignant Catarrhal Fever Erosions develop MvV Malignant Catarrhal Fever

Malignant Catarrhal Fever Epithelial erosions, severe encrustation of the nostril. MvV Malignant Catarrhal Fever

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

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

Malignant Catarrhal Fever Severe Ocular lesions mvv Painful Conjunctivitis Malignant Catarrhal Fever

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

Malignant Catarrhal Fever Severe Ocular lesions Eye lesions are almost pathognomonic. Almost always present in cattle, corneal opacities are bilateral and begin at lateral limbus and progress to center. Hypopion, ulceration, complete opacity and blindness ensue. MvV Characteristic eye lesions Malignant Catarrhal Fever

Malignant Catarrhal Fever Severe Ocular lesions mvv Characteristic eye lesions Malignant Catarrhal Fever

Malignant Catarrhal Fever Severe Ocular lesions mvv Malignant Catarrhal Fever

Oral Lesions Erosions on gums, dental pad and near teeth No lesions on the dorsal surface of the tongue. MvV Malignant Catarrhal Fever

Oral Lesions Erosions near the teeth mvv Malignant Catarrhal Fever

Oral Lesions Necrosis of papillae similar to rinderpest mvv Malignant Catarrhal Fever

Oral Lesions Erosions here are similar to bluetongue in Africa mvv Malignant Catarrhal Fever

Malignant Catarrhal Fever Oral Lesions cb Erosions of papillae Malignant Catarrhal Fever

Malignant Catarrhal Fever Oral Lesions mvv Malignant Catarrhal Fever

Erosions in squamous (anterior) portion of nasal cavity cb Erosions in squamous (anterior) portion of nasal cavity Malignant Catarrhal Fever

Enlarged and edematous Lymph nodes become enlarged if the animal has survived more than a few days of the disease. On cross section the lymph nodes are edematous and sometimes hemorrhagic. M. van Vuuren Enlarged and edematous lymph nodes Malignant Catarrhal Fever

Malignant Catarrhal Fever Moist necrotic dermatitis with exudation and encrustations Skin lesions associated with both sheep form and wildebeest derived. Resembles foot-and-mouth disease mvv Malignant Catarrhal Fever

Malignant Catarrhal Fever Mild diarrhea sometimes seen which is black and tarry, but not effusive Malignant Catarrhal Fever

Malignant Catarrhal Fever In terminal stages CNS symptoms: falling, circling, head pressing, high stepping convulsions, then death mvv Malignant Catarrhal Fever

Clinical Signs in Swine From a case in Norway: Symptoms reported as: hyperemic conjunctiva, vomiting, restlessness and anorexia. The rectal temperature was 41° C, the respiratory rate was 33 per minute, and the heart rate was 110 per minute. Despite parenteral antibiotic treatment, the symptoms worsened and the pig died 5 days after onset of disease. Over a short period, three other adult swine in the same herd died after showing similar clinical signs. LYken T, Aleksandersen M, Reid H, Pow I: Malignant catarrhal fever in swine caused by Ovine herpesvirus-2 in Norway. Vet Rec 143:464-467, 1998 September 11, 2003 — Michael Meredith (ed. Harry Snelson) Malignant catarrhal fever (MCF) is usually encountered as a fatal infectious disease of cattle and cervids (deer). The disease occurs world-wide but is not common except in some parts of Africa. Wild ruminants can be sub-clinical sources of MCF in Africa and sheep can be an important asymptomatic reservoir of the virus elsewhere. Now the sheep-associated MCF virus, Ovine Herpesvirus 2 (OvHV-2), has been identified in Swiss pigs as the causative agent of a disease which has been termed Porcine Malignant Catarrhal Fever (PMCF). The Swiss researchers suggest that the disease may be "heavily underestimated" in swine because the clinical signs and diagnostic procedures are not generally known. In sheep, MCF virus excretion occurs in semen and sexual transmission of OvHV-2 is believed to be important in the epidemiology of the virus. Bratberg B: Acute vasculitis in pigs: a porcine counterpart to malignant catarrhal fever. Proc Congress Internatl Pig Vet Soc, Copenhagen, Denmark, p. 353, 1980 Kurtze H: Überträgung des “Bösartigen Katarrhalfiebers des Rindes” auf ein Schwein. (In German). Deutsche Tierärtzliche Wochenschrift 57:261, 1950 In sheep, MCF virus excretion occurs in semen and sexual transmission of OvHV-2 is believed to be important in the epidemiology of the virus. http://www.aasv.org/news/story.php?id=738 Malignant Catarrhal Fever

Clinical Features Summary Incubation period is LONG – weeks to months Morbidity LOW Clinical illness – weight loss, enlarged lymph nodes, corneal opacity, rhinitis Mortality – 100% Dr Corrie Brown Malignant Catarrhal Fever

Malignant Catarrhal Fever Diagnosis at Necropsy The disease is systemic and lesions can be found in any organ Inflammation and necrosis of the respiratory, alimentary and urinary mucosa Generalized lymphoid proliferation and necrosis Widespread vasculitis Malignant Catarrhal Fever

Focally disseminated erosions and ulcerations in the GIT Professor Moritz van Vuuren Focally disseminated erosions and ulcerations in the GIT Malignant Catarrhal Fever

Focally disseminated erosions and ulcerations in the GIT Professor Moritz van Vuuren Erosions ocurr from the esophagus to the rumen. Prominent lesions in the abomasum is common feature of MCF. Focally disseminated erosions and ulcerations in the GIT Malignant Catarrhal Fever

“button ulcers” 5-10 cm erosions Professor Moritz van Vuuren Focally disseminated erosions and ulcerations in the GIT “button ulcers” 5-10 cm erosions Malignant Catarrhal Fever

Malignant Catarrhal Fever Professor Moritz van Vuuren Frequently see erosions in the bladder mucosa Malignant Catarrhal Fever

Malignant Catarrhal Fever Professor Moritz van Vuuren Lymphoid infiltration Malignant Catarrhal Fever

Multifocal lymphoid infiltration Professor Moritz van Vuuren Prominent white nodules representing intramural and perivascular proliferation may be apparent. (Merck Veterinary Manual 9th Ed.) Multifocal lymphoid infiltration Malignant Catarrhal Fever

Multifocal lymphoid infiltration Professor Moritz van Vuuren Multifocal lymphoid infiltration Malignant Catarrhal Fever

Malignant Catarrhal Fever

Enlarged lymphoid tissue – everywhere – looks like lymphoma Dr Corrie Brown Tonsils bulge Lymph nodes – TOO BIG Malignant Catarrhal Fever

Hemal nodes are prominent Dr Corrie Brown Spleen infiltrated Malignant Catarrhal Fever

Peyer’s patches stand out Dr Corrie Brown Peyer’s patches stand out Malignant Catarrhal Fever

Malignant Catarrhal Fever Diagnosis Dr Corrie Brown Malignant Catarrhal Fever

Malignant Catarrhal Fever Diagnosis Dr Corrie Brown Malignant Catarrhal Fever

Malignant Catarrhal Fever Histopathology T lymphocyte hyperplasia, cell necrosis T lymphocyte hyperplasia, cell necrosis Malignant Catarrhal Fever

Malignant Catarrhal Fever Histopathology Severe necrotizing vasculitis Perivascular lymphoid infiltration Malignant Catarrhal Fever

Malignant Catarrhal Fever Histopathology Perivascular lymphoid infiltration of arterioles Malignant Catarrhal Fever

Malignant Catarrhal Fever Summary Think Malignant Catarrhal fever when: Only a few cattle are affected and they die Cattle have been exposed to sheep during lambing season Cattle have severe respiratory symptoms and conjunctivitis with cornel opacity Lesions are on the ventral side of the tongue Malignant Catarrhal Fever

Malignant Catarrhal Fever This presentation is a collaborative effort Malignant Catarrhal Fever