[Equine arteritis virus: clinical symptoms and prevention].

The research study discusses the increasing prevalence of equine arteritis virus (EAV) among horses in European countries with emphasis on its clinical symptoms and control measures.

Clinical Symptoms and Consequences of EAV

• Equine arteritis virus (EAV) has demonstrated a rise in incidences of respiratory disease and abortion in horses. The virus has been prevalent in most European countries.
• Upon acute infection, virus is eliminated by mares (female horses) and geldings (castrated male horses), however, 30% to 60% of stallions (male horses) become persistently infected.
• In persistently infected stallions, the virus is retained within the reproductive tract and gets continuously shed in the semen. This kind of EAV persistence does not affect the fertility of stallions.
• Mares receiving semen contaminated with EAV can have acute infections, leading to shedding large quantities of the virus in respiratory secretions and urine.
• This shedding contributes to the lateral spread of the virus and can lead to other horses becoming susceptible to infection. Late-stage pregnancy infections in mares can result in abortions.

Prevention of EAV Spread

• The study emphasizes the importance of identifying virus-shedding stallions to control the spread of EAV effectively.
• Stallions identified as persistently infected should either not be used for breeding, or should only breed with seropositive mares (mares that have antibodies to the virus).
• Mares that have been bred to shedding stallions should be kept in isolation from other animals for a period of 3 weeks post-insemination. This measure is aimed to prevent the lateral spread of EAV to other susceptible horses.

In conclusion, while horses affected by EAV can manifest adverse symptoms, strategic management and isolation strategies can limit the spread of the contagion, making it critical to monitor and take precautionary measures within horse populations.