Detection and Management of an Outbreak of Equine Herpesvirus Type 1 Infection and Associated Neurological Disease in a Veterinary Teaching Hospital

Abstract

Background: Because of the serious disease sequelae associated with equine herpesvirus type 1 (EHV-1) infections, awareness and control measures used to control outbreaks are important issues for all horse populations.Objectives: Describe the occurrence and management of an outbreak of EHV-1 infection at a veterinary hospital. Animals: Horses hospitalized at a referral veterinary hospital. Methods: A horse with myeloencephalopathy associated with EHV-1 infection (EHM) was admitted for diagnostic evaluation and treatment under strict infection control procedures. We describe the occurrence and management of a nosocomial outbreak of EHV-1 infections associated with admission of this patient.Results: Despite institution of rigorous biosecurity precautions at the time of admission of the index case, EHV-1 infections spread to 6 other horses that were hospitalized at the James L. Voss Veterinary Teaching Hopsital, including 2 that served as sources of infection for horses on their home premises after discharge. Infection with EHV-1 was confirmed by polymerase chain reaction (PCR) and by seroconversion documented by glycoprotein G ELISA. A voluntary quarantine was imposed and admissions were restricted to prevent additional horses from being exposed. Quarantine duration was abbreviated by serial testing of all horses with PCR.Conclusions and Clinical Importance: These findings illustrate the contagious disease risk that can accompany management of horses with EHM. Horses with active nasal EHV-1 shedding should be isolated in an airspace that is separate from other horses by strictly enforced biosecurity and isolation procedures. Serial testing with PCR may be a useful adjunct to determine when the risk of transmission has been minimized.

Genetic diversity of equine herpesvirus 1 isolated from neurological, abortigenic and respiratory disease outbreaks

“…Respiratory infections are common, and the virus can also cause multiple abortion outbreaks, neonatal death and neurological damage that may lead to fatal paralysis (Goehring, Landolt, & Morley, 2010; Irwin et al., 2007; Mumford et al., 1987; Schulman, Becker, van der Merwe, Guthrie, & Stout, 2014). After initial infection of the upper respiratory tract epithelium, a highly cell‐associated viraemia develops (Gibson, Slater, & Field, 1992; Scott, Dutta, & Myrup, 1983).…”

Nosocomial Infections and their Surveillance in Veterinary Hospitals

“…Even though loads of recommendations for prevention and control of nosocomial infection is available out of the lesson learnt from previous experiences (Hartmann et al, 1996;Wright et al, 2005;Dallap et al, 2010;Goehring et al, 2010;Steneroden et al, 2010). Presently there is no recognized or published principles or standards for surveillance and control of infection in veterinary hospitals, which makes the system weak to determine rates and fraction of nosocomial and preventable infections respectively (Morley, 2002(Morley, , 2004Benedict et al, 2008;Morley and Weese, 2008).…”

“…Prevalence studies have shown that 4-9% patients endure from a nosocomial infection (Mielke, 2010). The occurrence of nosocomial infections in veterinary hospitals has not been well established and in nascent stage (Boerlin et al, 2001;Johnson, 2002;Morley, 2004;Smith, 2004;Traub-Dargatz et al, 2004;Morley and Weese, 2008), even though the nosocomial infections are of immense significance in the field of veterinary medicine since quite a lot of March 2015 | Volume 3 | Special issue 2 | Page 2 nosocomial outbreaks of different etiologies in veterinary hospitals has been documented (Castor et al, 1989;Madewell et al, 1995;Hartmann et al, 1996;Konkle et al, 1997;Tillotson et al, 1997;Seguin et al, 1999;Weese and Armstrong, 2003;Cherry et al, 2004;Wright et al, 2005;Weese et al, 2006a;Dallap et al, 2010;Goehring et al, 2010;Steneroden et al, 2010). Six of those outbreaks had evidence of zoonotic infection (Konkle et al, 1997;Seguin et al, 1999;Cherry et al, 2004;Wright et al, 2005;Weese et al, 2006a).…”

Nasal Shedding of Equid Herpesvirus Type 1 and Type 4 in Hospitalized, Febrile Horses

“…Finally, if a case of EHV-1 or EHV-4 infection has been identified, any further fevers in hospitalized horses need to be investigated, and rectal temperatures during a time like this should be collected at least twice daily in all hospitalized horses [4].…”

“…Over the last decade, there have been several reports on nosocomial spread of EHV-1 infection in hospitalized horses, including development of equid herpesvirusassociated myeloencephalopathy (EHM) [3][4][5]. These infections have led to fatal losses of patients and voluntary quarantine of equine hospitals, with substantial financial losses and were associated with significant loss of image for the affected institutions, as perceived by the public.…”