APHA/Defra give an update on some recent changes and potential notifiable equine disease threats worldwide.
As we move into summer, vector-borne disease becomes more concerning. Last year West Nile Virus (WNV) was reported in Germany, France, Spain, Portugal, Greece, and Hungary in equids, and in birds in Spain and Slovenia. Infected mosquitos were also detected in the Netherlands.
Given the relative proximity of these countries to GB and the fact that GB has localised foci of competent vectors in the South East of England, owners and practitioners should be vigilant for clinical signs of the disease and consider vaccination against WNV if they are travelling to endemic regions in Europe. Although mosquitoes are more important for transmission, birds are the natural reservoir hosts of Flaviviruses such as WNV, particularly passerine species, which typically migrate to the UK for the summer breeding season.
Australia has detected Japanese encephalitis (JE), another mosquito-transmitted disease, in February 2022 for the first time in piggeries in New South Wales, Victoria, South Australia and Queensland. This was declared a communicable disease incidence of national significance on March 4th. Like WNV, horses are susceptible dead-end hosts i.e., they do not develop viremia of sufficient titre to infect mosquitoes and thus, do not directly present a threat to the human population. Signs in horses are usually mild and signs of the disease include high temperature, jaundice, lethargy, anorexia, and neurological signs which can vary in severity. Neurological signs can include incoordination, difficulty swallowing, impaired vision, and in rare cases, the horse may become over excited. There are currently no vaccines available for horses and the likelihood of a case occurring here is very low but could be associated with travel.
In 2010 the EU imposed protective measures laying down a specific regime for the movement of equids from Romania. The measures were adopted in respect of equine infectious anaemia (EIA) and the disease situation, whereby culling affected animals had not historically been implemented. In February 2022 Romania was able to demonstrate that the national EIA eradication scheme was sufficiently effective to ensure the safe movement of equids between member states. Therefore, the EU safeguard measure has been repealed, easing movement of equids from Romania to the rest of the EU. In GB, pre- and post import testing for EIA will remain in place for direct consignments of equids entering from Romania, for the time being.
The International Disease Monitoring team monitor for major, notifiable, or new and emerging animal disease outbreaks internationally and in the UK. This is done as an early warning to assess the risk they pose to the UK, in particular those diseases which impact on animal health and welfare, international trade, public health, or wider society. The maps they produce are available to view here.