Epizootic haemorrhagic disease (EHD)

There has never been a reported case of epizootic haemorrhagic disease in Great Britain. Outbreaks of EHD  in cattle have been reported (Gov.UK) for the first time in southern Europe in November 2022. They are currently affecting France, Spain, Portugal and Italy.

EHD does not affect humans or food safety. However, it can cause large outbreaks in susceptible animals. This can have a significant impact on trade.

Suspicion and confirmation

Epizootic haemorrhagic disease is a notifiable animal disease (Gov.UK). If you suspect it you must report it immediately. Failure to do so is an offence.

Contact your local Animal and Plant Health Agency (APHA) office immediately at 0300 303 8268, if you suspect EHD.

APHA vets will investigate suspected cases.

Clinical signs

Clinical signs occur mainly in cattle and cervids. In cattle these include:

• anorexia, dejection 
• lameness, stiff gait
• congestion, lip/mouth ulcers, lingual prolapse (tongue hanging out like a dog)
• conjunctiva, watery eyes, bulging eyes
• periocular oedema, nasal discharge 
• congestion, petechiae, erosions, ulcers, scabs on the muzzle
• oedema and/or congestion of the coronary bulges associated with lameness
• oedema pastures, fetlock, cannon, carp, shank 
• erosions, ulcers, scabs, petechiae at the udder 

Wild ruminants such as deer may also:

• have a swollen face
• have redness of the eyes and mouth
• have excessive bleeding (in diarrhoea and urine)
• be dehydrated

Sheep, goats, and camelids are also susceptible to EHDV infection, but seldom develop obvious clinical signs of the disease. 

Transmission 

EHDV is transmitted via arthropod vectors, principally Culicoides biting midges. At least eight different viral serotypes have been recognised.

Infection with EHD typically happens when midges carrying the disease, bite susceptible animals. The weather (especially temperature and wind direction) affects how the disease can spread. EHD could also spread to the UK if infected live animals are imported from countries where EHD is circulating.

The possibility of transmission through germinal products such as semen or embryos, or iatrogenic transmission (e.g. contaminated needles) is unknown but cannot be excluded.

Prevention and control 

There is no commercially available vaccine to protect against EHD.

You can help to prevent the disease by practicing good biosecurity on your premises.

Control and ultimately eradication of EHDV is challenging once established. This is due to the vector-borne nature of the disease. If EHD is confirmed, the outbreak will be controlled in line with the contingency plan for exotic notifiable diseases (Gov.UK).

EHDV requires differential diagnosis using serological testing or PCR to discern EHDV from Bluetongue Virus (BTV). 

Keepers considering importing susceptible animals from EHD affected countries should consult their vet on the risks and health status of animals. This should be done before deciding to import.