title: Prevalence factors associated with equine herpesvirus type 1 infection in equids with upper respiratory tract infection and/or acute onset of neurological signs from 2008 to 2014.
abstract: The objective of the present case-control study was to determine prevalence factors associated with the detection of equine herpesvirus type 1 (EHV-1) by quantitative PCR (qPCR) in horses presented to veterinarians with clinical signs related to an upper respiratory tract infection and/or acute onset of neurological disease from March 2008 to December 2014. Nasal secretions and whole blood from 4228 equids with acute onset of fever, respiratory signs and/or neurological deficits were tested by qPCR for EHV-1. Categorical analyses were performed to determine the association between observations and EHV-1. A total of 117/4228 (2.7 per cent) equids tested qPCR-positive for EHV-1, with most of the isolates belonging to the non-neuropathogenic genotype (N752). EHV-1 PCR-positive equids were over-represented in racing horses. Depression, anorexia, nasal discharge and coughing were significantly less frequently reported in the EHV-1 qPCR-positive equids compared with the EHV-1 qPCR-negative cases. Neurological deficits were more frequently reported in the EHV-1 qPCR-positive cases. This study provides contemporary information on the frequency of EHV-1 detection by qPCR in blood and nasal secretions from horses with fever, respiratory signs and neurological deficits.
authors.affiliation: Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA, USA.
authors.forename: N
authors.initials: N
authors.lastname: Pusterla
authors.affiliation: Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA, USA.
authors.forename: S
authors.initials: S
authors.lastname: Mapes
authors.affiliation: Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA, USA.
authors.forename: N
authors.initials: N
authors.lastname: Akana
authors.affiliation: Merck Animal Health, Summit, NJ, USA.
authors.forename: C
authors.initials: C
authors.lastname: Barnett
authors.affiliation: Merck Animal Health, Summit, NJ, USA.
authors.forename: C
authors.initials: C
authors.lastname: MacKenzie
authors.affiliation: Merck Animal Health, Summit, NJ, USA.
authors.forename: E
authors.initials: E
authors.lastname: Gaughan
authors.affiliation: Merck Animal Health, Summit, NJ, USA.
authors.forename: B
authors.initials: B
authors.lastname: Craig
authors.affiliation: Merck Animal Health, Summit, NJ, USA.
authors.forename: D
authors.initials: D
authors.lastname: Chappell
authors.affiliation: Merck Animal Health, Summit, NJ, USA.
authors.forename: W
authors.initials: W
authors.lastname: Vaala
mesh_terms: D000208:Acute Disease; D000818:Animals; D016022:Case-Control Studies; D006566:Herpesviridae Infections / Q000453:epidemiology / Q000662:veterinary* / Q000821:virology; D004861:Herpesvirus 1, Equid / Q000235:genetics / Q000302:isolation & purification*; D006734:Horse Diseases / Q000453:epidemiology / Q000821:virology*; D006736:Horses; D009422:Nervous System Diseases / Q000453:epidemiology / Q000662:veterinary* / Q000821:virology; D015995:Prevalence; D060888:Real-Time Polymerase Chain Reaction / Q000662:veterinary; D012141:Respiratory Tract Infections / Q000453:epidemiology / Q000662:veterinary* / Q000821:virology; D012307:Risk Factors
keywords: Disease surveillance; Herpesviruses; Horses; PCR