The Welara Journal

  The International Collating Center, Newmarket, United Kingdom (UK), and other sources reported the following disease outbreaks.

  One case of contagious equine metritis (CEM) was reported from France and limited numbers of cases were reported from Italy. The USA reported no spread of infection from the Arabian stallion in California that was cultured positive for T. equigenitalis earlier this year. Also, 226 stallions in 24 states were tested as part of a voluntary national stallion screening program for CEM, all with negative results.

  Outbreaks of equine herpesvirus-1 (EHV-1) were reported from Germany (one case), Ireland (one case of abortion), Japan (two cases of abortion), and South Africa (10 abortions). EHV-1 myeloencephalopathy was recorded in Italy (three cases in Standardbreds at a racetrack), Japan (one case), and the UK. The UK outbreak involved seven recently imported donkeys, most of which developed respiratory signs, with two also exhibiting signs of mild ataxia and bladder paralysis. Ireland reported one case of respiratory disease due to EHV-4.

  Equine influenza was reported from the UK and the USA. Six outbreaks were diagnosed in the UK, most involving isolated cases in non-vaccinated equids. In some instances, affected animals had a recent history of importation or having come from a dealer’s yard. The causal strain of virus in all instances belonged to the Florida sublineage clade 2 of the American lineage H3N8 equine influenza virus. The USA reported four cases at a racetrack in Kentucky.

Outbreaks of strangles were recorded in France (10 premises), Germany, Ireland, Singapore, South Africa (five premises), Sweden, Switzerland, the UK, and the USA. Sweden, the UK, and the USA consider the disease endemic in their respective equine populations.

  France, Spain, and the United Arab Emirates (UAE) consider equine piroplasmosis (EP) endemic in their respective equine populations. The USA reported infection with Theileria equi in 410 of 2,362 horses tested, the vast majority on the index premises in southern Texas reported previously. Positive horses in six states were epidemiologically linked to that premises. Testing for EP is required for entry to sanctioned racetracks in New Mexico, Texas, Oklahoma, Colorado, and Louisiana. While nearly all of the seropositive horses identified so far have been positive for T. equi, a very small number of horses with Babesia caballi have also been detected. Epidemiologic investigations and testing are continuing.

  The USA reported 188 cases of Eastern equine encephalomyelitis (EEE ) during the third quarter of 2010. Florida (91) and Michigan (56) had the majority of cases, with fewer cases in eight additional states.

  West Nile encephalitis (WNE) was reported from Italy, Spain, the UAE, and the USA. There were outbreaks in three locations in Italy. Spain and the UAE each confirmed mild infections in two horses. In the USA, 101 cases were diagnosed: California (38 cases), Florida (17 cases), and the remainder in 22 other states. The vast majority of affected horses were not vaccinated against WNE or the vaccination history was not up to date.

  Equine infectious anemia (EIA) was reported in France, Germany, Italy, and the UK. Cases were diagnosed on three premises in France, some representing horses imported from Romania. Germany reported 12 EIA cases. Movement restrictions have been imposed, and epidemiologic investigations are ongoing. Italy reported one outbreak of EIA and provided findings from a national survey of all equids in the country. Inapparent EIA infections were diagnosed in 133 of 150,733 horses (0.1%), 12 of 7,433 donkeys (0.16%) and 92 of 861 mules (10.7%). The UK reported isolated cases on separate premises, including one equid that had recently been imported.

  Reports of equine viral arteritis were received from Germany (three clinical cases) and Italy (7.2% prevalence, with the highest prevalence in Standardbreds). Four carrier stallions (mostly Standardbreds) were allowed to breed under restrictions.

  Potomac horse fever (five cases in Kentucky), Hendra virus infection (one case in Queensland), and grass sickness (two cases in Switzerland) were also reported. . .