Equine disease surveillance: quarterly summary.

This research article summarizes the occurrence of various equine diseases observed in a quarterly period both within the UK and internationally. Specifically, it discusses incidents of equine influenza virus (EIV), contagious equine metritis (CEM), and dourine across different regions.

Equine Influenza Occurrence

• The article begins by detailing the observation of equine influenza virus (EIV) in the UK. Two cases were confirmed during summertime, which is typically a period of higher horse movement due to shows and events.
• These cases confirmed in Wiltshire and North Lanarkshire involved non-vaccinated horses exhibiting typical symptoms like coughing and nasal discharge. Diagnosis confirmation came through methods like haemagglutination inhibition (HI) assay and nucleoprotein antigen ELISA.
• Internationally, the presence of EIV, specifically the H3N8 strain, was reported in Ulaanbaatar City, Mongolia in July. Seven horses out of a group of 418 were infected.
• A widespread occurrence of the same EIV variant was later reported across multiple parts of Mongolia with over 74,000 cases and 40 deaths.

Contagious Equine Metritis Cases

• The report tracks a single instance of contagious equine metritis (CEM) in a French trotter mare in Calvados, Normandy. Diagnosis was confirmed through bacterial culture of the CEM organism (CEMO; Taylorella equigenitalis) from a uterine swab.
• Another CEM case was reported in an Arabian stallion in Arizona, USA, which was diagnosed via semen culture as part of a pre-export test. The disease’s origin was unknown, and no relationship was evident between this horse and previously observed CEM cases in the USA. Measures like quarantine and treatment were initiated to manage the situation.

Dourine Outbreaks

• The article finally reports on multiple outbreaks of dourine, a sexually transmitted disease caused by Trypanosoma equiperdum, in Italy between May and June.
• The infected horses, which were confirmed via the complement fixation test (CFT), were spread across various premises in Sicily and Napoli.
• The origins of infection were traced back to a Friesian stallion and a mare that had attended the farm for breeding. Further tracing led to the identification of additional affected stallions and other cases in Casoria and Nola.
• A subsequent retrospective survey revealed a significant number of samples positive for dourine in multiple regions of Italy. Additional serological tests were carried out to contain the situation, but the results needed to be interpreted cautiously due to uncertainty over the test’s specificity and the absence of clinical disease information.

The manuscript ends by stating that investigations are continuing into all retrospective serological diagnoses of dourine. All this information represents valuable data for planning disease control and prevention strategies in susceptible equine populations.