Warble Fly

If notifiable disease is suspected, contact DAERA on 0300 200 7840 or your local DAERA Direct Regional Office. Failure to do so is an offence

Current Situation

The last outbreak in Northern Ireland was in 1996.

Clinical signs

The main sign of warble fly is large, soft and painful swellings on the back of the animal of up to 3 millimetres wide.

What is the public health risk associated with this disease?

There is no public health risk associated with Warble Fly. It does not affect humans.

How is the disease transmitted?

The disease is spread by the Warble Fly, which lays eggs on the hide of animals.

Prevention

Good biosecurity is essential to the prevention of introduction of Warble Fly into Northern Ireland. You can help prevent Warble Fly by practising good Biosecurity measures. 

Controlling Warble Fly if suspected or confirmed in NI

Until satisfactory treatment has been carried out the affected animals or herds are subject to movement restrictions. Because of the life-cycle of the warble fly and because of the limitations on the use of the treatments available it is not always possible to treat cattle satisfactorily at the time the infestation is discovered or suspected and in some cases movement restrictions have to be retained for several months.

Single Lifetime Identification Document for Equines (“Horse Passports”)

All equines in Northern Ireland need to have a Single Lifetime Identification Document (commonly referred to as a “horse passport”) to identify them.

Further information on how to obtain a horse passport.

More useful links

International-Codes-of-Practice-2025_ITBA.pdf

HBLB International Codes of Practice | Home

Horse Illnesses: Equine Disease Prevention | The British Horse Society