Pathogen test The qPCR test detects the genome (DNA) of Equine Herpesvirus Type 2 (EHV-2). Serological detection of EHV-2 is of limited use to determine the re-activation of this herpesvirus. EHV-2 can remain latent in affected animals while shedding at levels adequate to infect other horses. Molecular detection of EHV-2 by qPCR is the most sensitive, specific and accurate tool in assessing the infectivity of an affected horse. Sample 1 nasopharyngeal swab - dry swab 5 mL - K3 EDTA tube 5 mL - liquor (CSF) - sterile tube Turnaround time 2 to 5 working days What is Herpesvirus Type 2? Equine Herpesvirus Type1 2 (EHV-2) was recently classified within the Gammaherpesvirinae subfamily. EHV-2 is widely spread in horse populations and it has been isolated from healthy animals as well as from horses with different clinical signs. EHV-2 is able to establish persistent infections. Various observations indicate that EHV-2 should not be neglected as a pathogen in equids. There are convincing results indicating that EHV-2 has a role as a predisposing factor for Rhodococcus equi invasion in the respiratory tract. Also as been suggested that EHV-2 may play a role in transactivation and reactivation of latent EHV-1 and EHV-4 infections. Clinical signs EHV-2 infection occurs most frequently in young foals, and the most common symptoms are keratoconjunctivitis, respiratory disease with pneumonia and pharyngitis, fever, enlarged lymph nodes, inappetence/anorexia, general malaise, and poor performance. There is no evidence that EHV-2 has abortigenic potential. Transmission The prowess of EHV-2 as a successfully adapted viral parasite of the horse is substantiated by seroepidemiological and virological studies which indicate almost universal acquisition of viral infection by young foals. The limited data collected supports the scenario that EHV-2, in aerosolised infective material excreted from the respiratory tract of another virus-shedding horse, enters the new host through the upper respiratory tract where it infects and replicates first in the respiratory mucosal epithelium. Prenatal infection with EHV-2 has not been recorded, and the virus has not been detected in colostrum or milk. Experimental infection of a mid-gestational equine foetus in utero resulted in normal term delivery, although the foal showed mild rhinitis and conjunctivitis, with nasal shed- ding of EHV-2. Prevention On the basis of evidence suggesting that EHV-2 infection can play an etiological role in predisposing foals to subsequent R. equi pneumonia, both passive immunisation with hyperimmune equine serum against EHV-2 and active immunisation with an vaccine containing EHV-2 glycoprotein antigens have been used, with reported success, for the prophylactic treatment of annual reoccurrences of this highly fatal foal disease. Ocular disease in foals associated with infection by EHV-2 on breeding farms has been successfully treated with ophthalmic ointments containing either idoxuridine or trifluridine together with antibiotics and non-steroidal anti-inflammatory agents.
