The common horse cold can be caused by many possible viruses in NZ. The top viral causes would be a Herpes Virus, or less likely an Adenovirus or Rhinovirus.
These viruses rarely cause serious disease in horses, however do cause a serious headache for their owners. The problem these viruses cause is coughing, which can be present for a long period of time, or they can cause a secondary infection. Both of these scenarios result in time lost riding and competing.
In Central Otago we appear to be having a viral recurrence with approximately 8 months in between local outbreaks when observed over the last 2.5 years.
The exact cause of your horses cold symptoms is often not diagnosed. This is because of costs associated with diagnosis, and also because most horses will recover quickly with the correct medical management.
Please DO NOT panic. Instead, can we please remember our hygiene practices:
Do not allow nose-nose contact between horses from different properties
Only handle your own horse and stay clear of other horses when out competing
Remember grooming kits are a great way of spreading viruses
Provide clean air environments for our horses when out competing; yards are better than stables. Better still are small paddocks
Allowing breaks when travelling to give horses time to graze grass will improve drainage of respiratory secretions and reduce compromise to the respiratory system
Hay steamers are fantastic for promoting respiratory health. Alternatively if horses are sick then soaking hay to swell dust particles does work well
Keep your Herpes Vaccinations up to date