Equine Herpes Virus-4 (EHV-4) Respiratory Disease
On 10th July 2015, Réseau d’Epidémio-Surveillance en Pathologie Equine (RESPE) confirmed three outbreaks of EHV-4 respiratory disease in Calvados, Lot-et-Garonne and Val D’Oise, with all diagnoses being confirmed by PCR on nasopharyngeal swabs.
In Lot-et-Garonne a vaccinated two-year-old Anglo-Arab filly on a stud with 10 animals had shown signs of fever and nasal discharge since 5th July 2015. In Val D’Oise a non-vaccinated three-year-old Lusitanian colt used for leisure had also shown signs of fever and nasal discharge since 5th July 2015. No details are available regarding the confirmed case in Calvados.
Equine Infectious Anaemia (EIA)
On 6th July 2015, the Ministry of Agriculture, Food and Forestry, Paris, reported a subclinical case of EIA near Alba La Romaine in Ardeche, south-east France to the World Organisation for Animal Health (OIE). The positive diagnosis was made on 4th May 2015 by Coggins test (agar gel immune-diffusion) conducted by the national laboratory at the National Food Security Agency (ANSES).
The following comments were published by the OIE regarding the known epidemiology of this event, which involves 25 other susceptible equidae in addition to the confirmed infected animal, which was humanely destroyed: “An epidemiological investigation was carried out in the various holdings where the equidae originated from. This investigation enabled to exclude the hypothesis of the origin of the outbreak as coming from another equidae kept with the infected animal in the vaccine production holding as all animals within this holding were negative with Coggins’test. Therefore it was considered not necessary to put under surveillance the holdings were the equidae originated from. Only the last holding, where the infected animal was kept, was placed under surveillance. Equidae within this holding which were in contact with the infected animal showed negative results to the Coggins’test (18 May 2015). Investigations are still on-going to identify the source of this isolated outbreak.”
UNITED STATES OF AMERICA
Eastern Equine Encephalomyelitis (EEE)
The number of confirmed equine cases of EEE in the USA for 2015 currently stands at nine, with cases of the disease reported in Florida (eight cases) and Virginia (one case). The four most recent cases in Florida have occurred in Leon, Orange, Marion and Alachua counties. Affected horses ranged in age from one and a half years to 14-years-old and all animals had to be euthanased. Three of the cases either had either not been vaccinated against EEE or the vaccination history was unknown. The fourth animal had last been vaccinated in October 2014. The case of EEE in Virginia was in a 12-year-old miniature mare in Chesapeake County that had not been vaccinated against EEE.
Equine Influenza (EI)
In late June 2015, EI was diagnosed in several horses at a show in Redmond, Oregon. The most recent reports list at least 15 affected horses ranging from one- to seven-years-old, the majority housed in the same barn. The disease is clinically characterised by pyrexia, coughing, nasal discharges, inappetance and lethargy. Additional cases of the disease are expected on the index premises. Owners of exposed horses that were at the show have been advised to quarantine their animals for at least two weeks and monitor them for signs of the disease.
Vesicular Stomatitis (VS)
According to the latest situation report issued by the USDA on 8th July 2015, VS has been confirmed on five equine premises in Colorado, including one in Delta County, three in Montrose County and one in Montezuma County. The latest findings bring the number of states affected by the disease in 2015 to five; New Mexico, Arizona, Utah, Texas and Colorado. Apart from Colorado, VS has been confirmed on five premises in three counties in New Mexico, 13 cases in Maricopa County in Arizona, one premises in Utah, and three premises in separate counties in Texas. All outbreaks so far reported have involved the New Jersey serotype of the virus. Additional premises in each affected county in Colorado are currently under movement restrictions as suspect premises.
West Nile Encephalitis (WNE)
WN virus infection was confirmed in late June 2015 in a horse of unknown vaccination status in Gavin County, Oklahoma. The affected animal displayed a range of neurological signs consistent with WNE.
Animal Health Trust
Information Exchange on Infectious Equine Disease
Lanwades Park, Kentford, Newmarket, Suffolk CB8 7UU, England
Telephone: + 44 (0) 1638 555399
Fax: + 44 (0) 1638 555659