The International Collating Centre, Newmarket, United Kingdom, and other sources reported the following equine disease outbreaks in the second quarter of 2018.

The Republic of South Africa (RSA) reported outbreaks of African horse sickness in most provinces in the country with the exception of the Western Cape. One outbreak was recorded in Swaziland.

Argentina, the United Kingdom, Uruguay, and the United States reported outbreaks of equine influenza. At least 42 cases were confirmed on 10 premises located in five provinces in Argentina. Three-year-old horses were principally affected. The strain involved belonged to clade 1, Florida sublineage of H3N8 virus. The United Kingdom and Uruguay recorded single outbreaks of the disease. Equine influenza was reported as endemic in the United States, occurring in four states, with multiple outbreaks in one state.

Germany, Ireland, Switzerland, the United Kingdom, and the United States recorded strangles. The number of outbreaks included six in Germany, outbreaks in all four provinces in Ireland and eight in Switzerland. The United Kingdom and the United States stated that the disease was endemic in their respective countries. More than 85 outbreaks involving 178 cases were recorded in 24 states in the United States.

Equine herpesvirus-1 (EHV-1) infection was reported by Belgium, Denmark, France, Germany, Greece, Ireland, Japan, RSA, Switzerland, the United Kingdom, and the United States. Infection associated with fever was diagnosed in three states in the United States. Respiratory disease was confirmed in Belgium (10 outbreaks), France (seven outbreaks), Germany (one case), Switzerland (one outbreak), the United Kingdom (one outbreak), and the United States (widespread in various states). EHV-1 abortion was recorded in Denmark (one case), France (eight cases), Germany (12 cases), Japan (nine cases involving seven premises), RSA (two cases), the United Kingdom (five cases of which three were on one premises), and the United States (two cases).

EHV-1 related disease in neonatal foals was diagnosed in France (one case) and the United Kingdom (two cases).

EHV-1 associated neurologic disease was reported from Denmark (two cases), France (four cases), Germany (one case), Ireland (two cases), and the United States (10 outbreaks in eight states; all but one involved single cases of the disease).

Equine herpesvirus-4 (EHV-4) respiratory disease was recorded in Argentina (four outbreaks), Belgium (one outbreak), France (59 outbreaks), Germany, RSA and Switzerland (each confirmed single cases of the disease), and the United Kingdom (four outbreaks). France and Germany reported single cases of EHV-4 abortion.

The United States recorded multiple cases of equine herpesvirus-2 and/or -5 infection in several states, some associated with a history of respiratory disease.

Equine infectious anemia was reported from Canada (single cases on two premises), Germany (one case), Greece (one case), and the United States (18 cases involving six states; 12 cases were in Texas).

The Republic of South Africa reported that equine piroplasmosis was widely present in the country with multiple cases of the disease confirmed in five provinces.

Germany confirmed Taylorella equigenitalis, the causal agent of contagious equine metritis in eight stallions and one mare, all of the Icelandic breed. Seven premises were involved.

Single cases of equine coital exanthema caused by equine herpesvirus-3 were recorded by Switzerland and the United States.

Cases of salmonellosis were reported from Ireland (one case) and the United States (12 cases, the majority associated with strains of salmonella belonging to serogroup B).

The United States confirmed three cases of equine neorickettsiosis (Potomac horse fever), and Germany one case of rotaviral diarrhea in a foal.

A single case of rabies was confirmed in Nebraska.

The United States recorded 10 cases of Eastern equine encephalomyelitis, all in Florida.

Single cases of West Nile encephalitis were reported from Brazil and RSA.

The Republic of South Africa also recorded 16 cases of encephalitis due to Middleburg virus infection and two cases due to Shuni virus infection.

Equine encephalosis was reported from RSA. Thirty-three cases were diagnosed in five provinces; these included seven in the Western Cape Province.

Rhodococcus equi infection is endemic in the United States; 14 cases were confirmed during the period under review.

Germany reported a case of anaplasmosis and Switzerland four cases of ehrlichiosis.

This is an excerpt from Equine Disease Quarterly, funded by underwriters at Lloyd’s, London.