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| + | ===Tick-borne fever=== |
− | Also Known As: '''''Pasture Fever''''' — '''''Tickborne Fever''''' — '''''Ruminant Anaplasmosis''''' — '''''TBF'''''
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− | Caused By: '''''Anaplasma phagocytophilum''''', previously known as '''''Ehrlichia phagocytophila''''' | + | *Caused by ''E. phagocytophila'' which has now been renamed as ''Anaplasma phagocytophilum'' |
| + | *Affects ruminants in Europe |
| + | *The tick ''Ixodes ricinis'' is the main vector |
| + | *Animals remain carriers for up to 2 years, but are immune to reinfection |
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− | ==Introduction==
| + | *Clinical signs |
− | [[File:Anaplasmosis.jpg|thumb|200px|right|''Rickettsia'' spp. inside tick haemolymph cells. Sourced from Wikimedia Commons]]
| + | **Incubation period of 2 weeks; recovery in 2 weeks |
− | [[File:Swollen tick-SteveFE.jpg|thumb|200px|right|''Ixodes'' tick. Sourced from Wikimedia commons]]
| + | **Fever, anorexia, reduced growth rates in young animals |
− | Tick Borne Fever is a '''[[Rickettsiales |rickettsial]]''' disease affecting the '''[[Leucocytes |white blood cells]]''' of sheep and cattle, causing '''anaemia''' and seasonal “pasture fever”.
| + | **Reduced milk production, abortion, still birth |
| + | **Leukopenia and thrombocytopenia |
| + | **Causes immunosuppression in young lambs causing susceptibility to tick pyaemia and louping ill |
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− | Seasonal pasture fever occurs in cattle that are returned to tick infected pasture in the Spring.
| + | *Diagnosis |
| + | **Intracytoplasmic morulae in [[Neutrophils|neutrophils]] of Giemsa-stained blood smears during acute phase |
| + | **Seroconversion detected by immunofluorescence |
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− | Human granulocytic ehrlichiosis, the '''zoonotic''' form of TBF is a potentially '''fatal''' disease reported in the UK, Europe and USA.
| + | *Treatment and control |
| + | **Oxtetracycline |
| + | **Tick control |
| + | **Prophylactic tetracyclines for lambs during first few weeks of life |
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− | ==Signalment== | + | ==Literature Search== |
− | TBF naturally affects primarily sheep and cattle, and less commonly, deer, horses and dogs.
| + | [[File:CABI logo.jpg|left|90px]] |
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− | ==Distribution==
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− | TBF has worldwide distribution including the UK. It is transmitted by '''''[[Ixodes spp. |Ixodes]]''''' ticks. Both adults and nymphs can transmit the disease. Transmission is '''[[Tick Disease Transmission |trans-stadial]].'''
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− | ==Clinical Signs==
| + | Use these links to find recent scientific publications via CAB Abstracts (log in required unless accessing from a subscribing organisation). |
− | TBF causes '''multisystemic''' disease, causing cardiovascular, gastrointestinal, respiratory, reproductive and neurological signs, and also lymphadenopathy and wasting disease.
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− | '''Severe haematological changes''' including profound [[:Category:Anaemia|'''anaemia''']] and '''leucopaenia''' cause significant clinical signs.
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− | Initial [[lymphocytopaenia]] and '''prolonged [[neutropaenia]]''' are also features of TBF.
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− | A profound '''[[eosinophilia]]''' will occur for 17-20 days post-infection. <ref>Miert, A. S. J. P. A. Mvan., Duin, C. T. Mvan., Schotman, A. J. H., Franssen, F. F. (1984) '''Clinical, haematological and blood biochemical changes in goats after experimental infection with tick-borne fever. '''''Vet Parasitology, ''16(3/4):225-233; 29 </ref>
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− | Low serum Alkaline Phosphatase (ALP) and decreased zinc, iron and albumin are also common biochemical findings, along with high [[urea]], [[creatinine]] and [[bilirubin]].
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− | Recovered animals develop immunity but it is unknown how long this is effective for.
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− | ==Diagnosis==
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− | Haematological and Biochemical changes as listed above along with '''marked pyrexia''' are highly suggestive, especially if historical findings are conducive.
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− | Demonstration of the '''organism''' in the '''[[Leucocytes |leucocytes]]''' in peripheral blood is confirmative.
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− | On '''post-mortem''' examination, the '''[[Spleen - Anatomy & Physiology|spleen]]''' is enlarged and mild liver damage is common. Lesions within the [[Lungs - Anatomy & Physiology|'''lung''']] are present and contain mononuclear infiltrate on histopathology. Thickening, ulceration and haemorrhage of the gastrointestinal tract become worse distally.
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− | The parasites may be visible within the neutrophils in sections of liver and lung.
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− | Antibodies can be detected using [[FAT|'''Indirect Immunofluorescence''' (IFAT)]], '''[[Complement Fixation]]''' and Immunoelectrophoresis (CIEP).
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− | ==Treatment==
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− | ''A. phagocytophilum'' is susceptible to '''oxytetracycline, sulphamethazine, sulphadimidine, doxycycline''' and '''trimethoprim-sulphonamides'''.
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− | ==Control==
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− | [[Tick Control|Control of the tick vector ]]is expensive but effective.
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− | Use of [[Ectoparasiticides |ectoparasiticides]] and tick resistant breeds is also valuable.
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− | ==Human Granulocytic Ehrlichiosis==
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− | Causes fever, malaise, headaches, sweats, nausea, confusion, anorexia, vomiting, weakness, diarrhoea, pneumonia, vertigo, seizures, GI bleeding and a skin rash.<ref>Bakken, J. S., Krueth, J., Tilden, R. L., Dumler, J. S., Kristiansen, B. E. (1996). '''Serological evidence of human granulocytic ehrlichiosis in Norway. '''''Eur J Clin Microbiol Inf Dis,'' 15(10):829-832; 12</ref>
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− | {{Learning
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− | |flashcards = [[Tick-Borne Fever Flashcards]]
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− | }}
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− | ==References==
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− | <references/>
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− | {{CABI source
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− | |datasheet = [http://www.cabi.org/ahpc/?compid=3&dsid=61126&loadmodule=datasheet&page=2144&site=160 tick-borne fever]
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− | |date = 6 June 2011
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− | }}
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| + | [http://www.cabi.org/cabdirect/FullTextPDF/2009/20093115234.pdf ''' Tick-borne disease testing: canine erhlichiosis and anaplasmosis.''' Alleman, R.; The North American Veterinary Conference, Gainesville, USA, Small animal and exotics. Proceedings of the North American Veterinary Conference, Orlando, Florida, USA, 17-21 January, 2009, 2009, pp 629-631 - '''Full Text Article'''] |
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− | {{review}}
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− | {{OpenPages}}
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− | [[Category:Rickettsiales]][[Category:Cattle Bacteria]][[Category:Sheep Bacteria]][[Category:Goat Bacteria]]
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− | [[Category:Zoonoses]]
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− | [[Category:Cardiovascular Diseases - Cattle]][[Category:Respiratory Diseases - Cattle]][[Category:Alimentary Diseases - Cattle]][[Category:Reproductive Diseases - Cattle]][[Category:Neurological Diseases - Cattle]][[Category:Lymphoreticular and Haematopoietic Diseases - Cattle]]
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− | [[Category:Cardiovascular Diseases - Sheep]] | + | [[Category:Rickettsiales]][[Category:Cattle]][[Category:Sheep]][[Category:Goat]] |
− | [[Category:Respiratory Diseases - Sheep]] | + | [[Category:To_Do_-_Bacteria]] |
− | [[Category:Alimentary Diseases - Sheep]][[Category:Reproductive Diseases - Sheep]][[Category:Neurological Diseases - Sheep]] | |
− | [[Category:Lymphoreticular and Haematopoietic Diseases - Sheep]] | |
− | [[Category:CABI Expert Review]][[Category:CABI AHPC Pages]]
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− | [[Category:Nick L]]
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− | [[Category:Cardiology Section]]
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