CSUVTHEHV-1 Infection Risk in Alpacas and Llamas
May 17, 2011

An outbreak of neurologic disease in horses caused by Equine Herpesvirus-1 (EHV-1) infections has developed during the past week in the Western US and Canada.  This outbreak is linked to horses that participated in a cutting horse show in Utah form April 29 to May 8.  Most horses returned to their originating farms before clinical signs developed.  It has since spread to most (if not all) of the Western states where there are reports of severely affected horses with neurlogic disease.  This EHV-1 outbreak has spread beyond primary cases (those attending the Utah horse show) and is now being reported among in-contact horses from the home premises. 

EHV-1 can also affect alpacas and llamas; however, at the time of this writing, there have been no reported alpaca or llama cases associated with the current horse outbreak.

Alpacas and llamas can become infected with EHV-1 following close contact with an infected equine, most likely through exposure to virus that is shed in nasal secretions or through indirect contact (hands, clothing, feeders, waterers, or other equipment).  Disease due to Equine herpesvirus-1 infection is uncommon in camelids.  Previous reports indicate that infected alpacas develop signs including blindness, changes in mentation and behavior, and other neurological signs.  Clinically affected animals often developed severe disease that may result in death or euthanasia of the animal.  Confirmation of a diagnosis in alpacas and llamas can be difficult since they do not seem to shed as much virus in nasal secretions or have virus in the blood like horses.  Thus, virus detection in nasal swabs and blood may be negative in infected camelids.  Acute and convalescent serology is recommended to help confirm a suspected infection or exposure in an alpaca or llama.  

Summary:

  • Currently, there is a highly virulent form of EHV-1 virus circulating in horses.
  • Alpacas and llamas that have contact with horses or other equids are at risk of EHV-1 infection. 
  • EHV-1 infection can result in severe and potentially fatal neurological disease in alpacas and llamas.
  • The risk of transmission from camelid to camelid is unknown but is likely low since infectious virus has not been detected in nasal secretions of camelids.

Recommendations:

  • Minimize contact between alpacas and llamas with horses, donkeys, mules, or other equids.  This is particularly important if the horses have recently traveled and were exposed to other horses.
  • Minimize movement of camelids and horses on or off home facilities.
  • If your alpacas or llamas have had recent exposure to horses, consider isolating them for a period of at least 3 weeks and not participating in any shows or sales.
  • Institute a quarantine program for animals entering your herd or returning from show, sale or breeding.  A minimum of 3 weeks at a distance of at least 100 feet is recommended.  Utilize separate boots, clothing, feed, and equipment for the quarantine area. 
  • Utilize a thorough biosecurity program in your herd to minimize introduction of infectious diseases to your herd.

More information about EHV-1 in horses: http://www.vetmed.ucdavis.edu/ceh/ehv1_general.cfm

If you have more questions, please contact your veterinarian or the CSU VTH at 970-297-5000.

Further reading: (3.8mb APHIS brochure)
http://www.aphis.usda.gov/vs/nahss/equine/ehv/equine_herpesvirus_brochure_2009.pdf

 
         
 

Google search for "Equine Herpesvirus" alpacas OR llamas OR camelids
About 3,600 at last check on 05-19-2011.

HorseTalk.nz