Changes

OPMV should be suspected in [[Viperidae]] presented with signs associated with immunodeficiency.  There are several methods of diagnosis:

OPMV should be suspected in [[Viperidae]] presented with signs associated with immunodeficiency.  There are several methods of diagnosis:

===Antemortem===

===Antemortem===

A haemaglutination inhibition test (HI) for specific antibodies to OPMV has been developed (titre < 1:20 - negative, 1:40 to 1:80 - suspect and > 1:80 - positive).  A positive titre means exposure and not disease or [[Snake Shedding|shedding]] status.  Two samples for HI at a 2-4 week interval are advisable.  Negative staining electron microscopy of faecal or lung samples is possible.  A polymerase chain reaction (PCR) would be very useful.

A haemaglutination inhibition test (HI) for specific antibodies to OPMV has been developed (titre < 1:20 - negative, 1:40 to 1:80 - suspect and > 1:80 - positive).  A positive titre means exposure and not disease or [[Snake Shedding|shedding]] status.  Two samples for HI at a 2-4 week interval are advisable.  Negative staining electron microscopy of faecal or lung samples is possible.  A polymerase chain reaction (PCR) test would be very useful.

'''For more information on sample collection, see''' [[Lizard and Snake Specimen Collection and Evaluation]].

'''For more information on sample collection, see''' [[Lizard and Snake Specimen Collection and Evaluation]].

===Postmortem===

===Postmortem===

* Gross necropsy - Lesions are usually subtle to non-existent but may include pulmonary (pneumonia - congestion, oedema, haemorrhage or inflammatory exudate) and pancreatic (necrosis, hyperplasia, interstitial oedema or fibrosis) lesions.  The liver may be involved.

* Gross necropsy - Lesions are usually subtle to non-existent but may include pulmonary (pneumonia - congestion, oedema, haemorrhage or inflammatory exudate) and pancreatic (necrosis, hyperplasia, interstitial oedema or fibrosis) lesions.  The liver may be involved.