The International Collating Center, Newmarket, England, and other sources reported the following equine disease outbreaks for the fourth quarter* of 2013.

Outbreaks of strangles were reported by Denmark, France, Germany, Sweden, and the United States. Denmark confirmed the disease in 15 of 50 horses in a riding school of which two had to be euthanized. Four outbreaks were recorded in France. One case was diagnosed in Germany. Strangles was considered endemic in Sweden and the United States with numerous outbreaks confirmed in several states, including Indiana, Kentucky, North Carolina, and Virginia, among others.

Germany, the United Kingdom (UK), and the United States recorded outbreaks of influenza. Isolated cases of the disease were diagnosed in Germany (one outbreak) and the UK (two outbreaks). The United States reported outbreaks in several states, California, Indiana, and New Jersey, among others, with horses exhibiting signs of varying clinical severity.

The United States was the only country to report limited serological evidence of equine arteritis virus infection in breeding stock in a few states.

Equine herpesvirus-1 and -4 (EHV-1 and -4) related diseases were recorded in France, Germany, Ireland, Japan, and the UK. Respiratory disease caused by EHV-4 was confirmed in France (12 outbreaks), Germany (seven cases on four premises), and the UK (five outbreaks with limited numbers of affected horses). Abortions due to EHV-1 were reported from Germany (one outbreak), Ireland (four outbreaks), Japan (three cases on two premises), Sweden (one outbreak), the UK (two outbreaks), and the United States (three outbreaks). Most affected premises had isolated cases of the disease.

EHV-1 related neurologic disease was confirmed in France (one outbreak in a riding school) and the United States (two outbreaks). One occurred at a racetrack and was associated with a non-neuropathogenic genotype strain of the virus. The second U.S. outbreak occurred at a riding school: Four horses died or had to be euthanized, and five other febrile in-contact horses were also confirmed infected with a neuropathogenic genotype strain of EHV-1.

A limited number of cases of EHV-2 and EHV-5 infection were reported in the United States.

Reports on equine piroplasmosis were received from France (endemic) and the United States (Theileria equi infection in one Quarter Horse racehorse).

Germany and the United States reported isolated cases/ outbreaks of Salmonella infection. One case was recorded in Germany, and 13 cases of Group B salmonellae involving multiple premises were confirmed in the United States.

Equine proliferative enteropathy due to Lawsonia intracellularis was reported in foals in several states including Kentucky (16 cases) and Ohio (one case).

The United States recorded one case of equine monocytic ehrlichiosis in Texas.

Cases of clostridial enteritis due to C. perfringens type A were reported from several states in the United States. Two cases of C. difficile were also diagnosed, both on premises in Kentucky.

Abortion due to leptospiral infection was recorded in France (one case) and the United States (six cases).

During the fourth quarter, the United States confirmed 40 cases of Eastern equine encephalomyelitis out of an annual total of 183 from 22 states. South Carolina (49), Florida (34), and Georgia (25) had the highest number of cases for 2013.

Reports of West Nile virus encephalitis were also received from the United States. Over a three-month period, 201 cases were diagnosed in a total of 41 states. The greatest number of cases was diagnosed in Texas (60), Oklahoma (41), and Montana (27).

Equine hendra virus infections were reported in Australia during the 3rd quarter of 2013. Isolated cases occurred on four separate premises in New South Wales and on one premises in Queensland.

Switzerland reported a single case of atypical myopathy.

*Third Quarter Report for Australia

This is an excerpt from Equine Disease Quarterly, funded by underwriters at Lloyd's, London, brokers, and their Kentucky agents.

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Equine Disease Quarterly

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