Frequently Asked Questions

• What is West Nile virus?
  West Nile virus is an insect transmitted viral disease. A disease that mainly affects birds: but can be transmitted to people, horse and other animals.
  
  Horses and people are the most susceptible to West Nile virus, where the disease can cause a potential fatal neurological disease. Death rates in horses that succumb to the neurological form of the disease range from 20 to 57%, whereas in people it is around 1%.
• Can horses infected with West Nile virus infect others?
  No. West Nile virus is transmitted by the bite of infected mosquitoes. The mosquito is only infected by taking a blood meal from birds. Virus transmitted to horses, by the bite of infected mosquitoes, does not replicate into high enough levels within the horse, and so mosquitoes taking a blood meal from the horse are not infected by the virus. Horses (and humans) are therefore considered ‘dead end’ hosts.
• Do I have to tell anyone if my horse is found to be infected with West Nile virus?
  Yes. As a notifiable disease in Europe any horse infected with West Nile virus must be notified to your country’s appropriate authority.
• Is there a cure for horses infected with West Nile virus?
  There is no definitive cure, although veterinary supportive treatment can aid its recovery and so save the horse’s life. However, in cases where the animal is not able to stand up their chance of survival is low and it may die or have to be put to sleep on humane grounds.
• How can I prevent animals from becoming infected?
  Eradicating disease carrying mosquitoes is impossible, although exposure can be reduced by using insecticides and eliminating where possible mosquito breeding areas. However, the only way to reduce the risk of your horse succumbing to the symptoms of West Nile virus is through vaccination.
• Can I vaccinate against West Nile virus?
  A vaccine, Duvaxyn WNV, is now licensed in Europe (Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, United Kingdom). However, in some countries vaccination may be prohibited by that country’s authorities due to their West Nile virus surveillance programmes.
• How do I obtain vaccine?
  Vaccine, if permitted for sale in your country, may only be obtained through your veterinary practice.
• If I am travelling with my horse to an area where West Nile virus is present, how far in advance would I need to vaccinate my horse before travelling?
  If your horse has not been vaccinated against West Nile virus then it will need to be a given a 2 dose primary course. This course, for Duvaxyn WNV, is given 3-5 weeks apart. Protection is achieved 3 weeks after this primary course. Therefore a horse would need to receive its first dose at least 6 weeks before it travels.