Equine Influenza
Equine flu can be prevented with regular vaccinations. In this blog, we explain they symptoms of equine flu and how to prevent and manage an outbreak.
What are the symptoms of Equine Flu?
Flu causes upper respiratory tract disease. Symptoms usually appear within 1-5 days of exposure to the virus.
Symptoms
- High Fever
- Harsh dry cough
- Nasal discharge
- Ocular discharge
- Loss of appetite
- Depression
These symptoms can be very similar to those seen with Strangles and with various cold viruses. It is important to differentiate these different respiratory diseases to ensure appropriate treatment. Vaccinated horses can still be infected but will only show mild symptoms so don’t assume that because your horse has been vaccinated they can’t have flu
What should I do if my horse has symptoms of equine flu?
If your horse is exhibiting any signs of respiratory disease it is important to isolate them immediately from other horses. Arrange for your vet to examine your horse and take samples for analysis.
How is Equine Flu transmitted?
Equine influenza is highly contagious; it is spread by inhalation of airborne droplets from infected horses. These droplets can travel a significant distance; they have been shown to travel several kilometres. Disease can also be spread by transmission of droplets on contaminated objects such as people’s hands or clothing, brushes, tack, mucking out equipment and haynets.
Managing an outbreak of equine flu
Stop all movement on and off the yard until you have received the all clear. Monitor the temperatures of other in-contact horses daily and record any clinical signs. Any horse with a temperature over 38.5°c should isolated and your vet called immediately. If your horse is not vaccinated speak to your vet about starting a new vaccination course.
Infected or suspicious cases should be kept isolated in a separate airspace from healthy horses, as far away as is practically possible, ideally at least 25 metres away. They should have their own separate grooming and mucking out equipment and a separate muck heap should be used.
All personnel should wear protective clothing, use a foot dip with clean disinfectant (Virkon or Dettol are good disinfectants) that is regularly changed and wash their hands following contact with infected cases. The isolated horses should be looked after last after all of the healthy horses. Tape off the isolation area and use signage to make all other owners aware to avoid the area.
What is the treatment for equine flu?
Isolation of infected cases is of vital importance to reduce spread. ‘Flu’ is caused by a virus so will not respond to antibiotics, but some horses will get a secondary bacterial infection and in these cases antibiotics will be warranted.
Infected cases can be made more comfortable by giving painkillers such as bute, this will help keep their temperature down and reduce the inflammation in their respiratory tract. Keeping them warm and dry and feeding soft food will also help infected cases to feel better.
The respiratory tract will be damaged by the virus and will need time to recover, it is important to give horses sufficient recovery time before resuming normal exercise. As a rule of thumb, horses should have 1 week off work for each day that they had a fever.
How to help prevent equine flu
All horses without exception should be vaccinated against ‘flu’. Even those that do not go out to shows are still at risk of infection if they are within 5km of other horses or if there are other horses travelling on and off the yard. Although the vaccination is not 100% effective at preventing ‘flu’, it does significantly reduce the severity of the clinical signs, horses will recover quicker and be less infectious to others on the yard.
All new horses arriving on a new yard should be isolated for a minimum of 2 weeks on arrival and there should be a yard protocol that all horses are vaccinated. If a horse needs to start a new vaccination course they would ideally wait 7 days before coming onto the new yard. When out at competitions or even when out hacking it is important to minimise contact between horses, do not allow your horse to sniff noses with other horses.
If you are going out competing take all your own equipment including water buckets and avoid communal areas. Disinfect all your equipment including your trailer or lorry when returning to the yard
Herd immunity
The more horses that are vaccinated the slower the spread of the virus. The principal of herd immunity was demonstrated by the reduction of the MMR vaccine that our children get when they are young.
In 1998 there was a scare about the safety of the MMR vaccine that resulted in a huge drop in the number of children being vaccinated and a significant rise in the number of measles outbreaks.
At present only 40% of the horse population are vaccinated against flu. If we can get this to 75% herd immunity will reduce the risk of flu epidemics. So when someone decides not to vaccinate their horse they are not just putting their own horse at risk but the whole equine population.
What is the equine flu vaccination course?
To start a new course horses will need to have the following:
- 1st Vaccine Flu & Tetanus
- 2nd Vaccine Flu & Tetanus (21 – 92 days after the 1st vaccine has been given)
- 3rd Vaccine Flu only (150 – 215 days after the 2nd vaccine) After the 3rd vaccine they will move to six monthly or annual boosters
The flu virus is constantly evolving and changing and the most recent outbreak is a particularly virulent strain. If your horse is going on and off the yard to lessons or competitions or others from the yard are doing the same, the current advice is to give a six month booster to increase their immunity to this particular strain.
If your horse never leaves the yard, others are not coming and going and you are not close to a big livery yard or competition centre then you are classed as relatively low risk and can choose to wait for the 12 month booster. It is ultimately your decision and you must way up the risk but your vet will be happy to discuss this with you.
If you would like any additional information please call us on 01577 841010.
