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| | ===Laboratory Tests=== | | ===Laboratory Tests=== |
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| − | In the United Kingdom, bluetongue is a notifiable disease and so samples from suspected cases should be submitted to the Institute for Animal Health (Pirbright) for laboratory diagnosis. Advice detailing the samples required is available from [http://www.defra.gov.uk/foodfarm/farmanimal/diseases/atoz/documents/bluetongue_technical.PDF DEFRA]. | + | In the United Kingdom, bluetongue is a notifiable disease and so samples from suspected cases should be submitted to the Institute for Animal Health (Pirbright) for laboratory diagnosis. Samples are collected from sheep with raised temperatures and include jugular blood collected into a plain tube to provide serum for an antibody test, and a heparinised blood sample to be used for PCR. Serum from in-contact ruminants is also submitted, as well as spleen and lymph node from all post-mortem cases. |
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| − | Version 1.5; 21 November 2002
| + | There is an array of laboratory tests available for the diagnosis of bluetongue, and the table below published by DEFRA<sup>1</sup> summarises these: |
| − | - A second 10 mL is added to an anticoagulant, in vacutainers or commercially
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| − | prepared disposable tubes. EDTA is the anticoagulant of choice if blood is to be
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| − | tested by PCR, but heparin is suitable for most purposes.
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| − | · Sera from 10–15 convalescent sheep (if there are any). If no convalescent sheep are
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| − | present, sera should be collected from in-contact sheep.
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| − | · Sera from in-contact cattle, ideally yearlings, and from other ruminants.
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| − | · Spleen and lymph nodes from all postmortem cases.
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| − | · Cardiac and skeletal muscle (especially if abnormal) in formol saline.
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| − | Transport of specimens
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| − | 6.13 Sera may be transported frozen at –20oC. Other specimens should be submitted
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| − | on wet ice and MUST NOT BE FROZEN. If ice blocks are used, extreme care should
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| − | be taken to ensure specimens do not contact the blocks. Direct contact with ice causes
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| − | freezing which lyses the blood cells thereby releasing, the predominantly cellassociated
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| − | virus that will be inactivated if antibody is present. Whole blood should be
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| − | held at 4°C.
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| − | 6.14 A full history and identification of samples is necessary.
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| − | Laboratory diagnosis
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| − | 6.15 Diagnostic tests currently available at Pirbright, what each detects and the time
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| − | required to obtain the results are shown in Table 1, below:
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| | ===Pathology=== | | ===Pathology=== |