Flu outbreak hits Australia

Earlier this year there were only two countries in the world that had never experienced equine flu – New Zealand and Australia.  New Zealand is still clear but Australia is now gripped by the most devastating equine disease outbreak in its history.

While Australia could, in some ways, be considered lucky, as it appears that the strain of flu virus introduced is one of the less virulent ones, the outbreak is still disrupting every aspect of the horse industry.  Top equine events are being cancelled and even the Melbourne Cup is under threat.  The breeding season is also suffering as movement restrictions stop stallions and mares being brought together.  In fact it is believed that up to 70% of brood mares in New South Wales may remain uncovered.

The numbers involved are sobering.  At the time of writing, on the 20^th September, less than a month after the outbreak began, 1,456 premises have been identified as infected, with another 362 dangerous contacts and 326 suspect properties.  Over 12,000 horses are held on the confirmed disease premises.  The numbers rise daily.  It has already cost the equine industry millions and it is estimated that the after-effects will be felt for many years to come. 

It is still not entirely clear how the disease spread around the country, however it is suspected that the virus was brought in with some horses from Japan which is also experiencing an outbreak.  This was, however, only announced six hours after the horses, which were in Japan for the breeding season, had left for Australia and were in mid-flight.  Much like the South Africa outbreak of 2003, these horses had come together from many parts of the world and while, in theory, properly vaccinated, this outbreak demonstrates that while vaccination with effective vaccines is essential, some vaccines used outside the UK do not stimulate or maintain a high immunity.

The virus carried into Australia by these horses managed to escape from the quarantine premises where they were held, probably accidentally carried on clothes.  Indeed, during the South Africa outbreak of 2003 the flu virus was transported over 600 km by indirect transmission in a lorry, leading to further cases.

Australia still hopes to eradicate disease, however they are considering the implementation of vaccination in some areas which may play a key role in the control of this outbreak.  In the meantime, vaccination is essential throughout the rest of the world to help prevent disease.