VHD: what every UK rabbit owner needs to know

Last revised March 2007

What is VHD?

Viral Haemorrhagic Disease. It’s a deadly disease that any rabbit can catch, and it kills most of those that get it. It first appeared in Britain in 1992 and was a notifiable disease until October 1996, when the MAFF (now DEFRA) lifted restrictions on affected premises - the disease had become so widespread that such measures were futile.

Only vaccination can control the spread of the disease in domestic rabbits. VHD is so deadly it has been released in Australia to kill wild rabbits with great success. The problem is, it kills pet rabbits too.

VHD is also sometimes referred to as HVD or RCD, particularly in Australia.

Is VHD the same as myxomatosis?

No. VHD is caused by a totally different virus and causes a totally different disease. Myxomatosis is caused by a virus from the Pox family, whereas VHD is caused by a member of the calicivirus family. Pet rabbits need to be vaccinated against myxomatosis and VHD. More information on myxomatosis can be found here:

Can humans or any other animals catch VHD?

No. Only rabbits get VHD, although hares can get a similar disease.

Does VHD affect wild rabbits in this country?

Yes, VHD is endemic (well established) in British wild rabbits, so they can help spread the virus around the country.

Which areas are affected?

VHD outbreaks have been reported across the entire UK, from the South coast to Scotland. Between 1992 and 1996 (the period when outbreaks were officially being monitored) the South West, Wales, and coastal areas were worst affected. However, in the decade since VHD ceased to be notifiable, we have had no way of knowing where VHD active, other than sporadic reports from rabbit owners and vets who come across the disease. Hopefully, this situation will soon improve, as a new national initiative attempting to monitor this, and other infectious diseases, was launched in February 2007.

Despite this, waiting for VHD to appear in your area before vaccinating may be too late for your rabbits…. Using this “wait and see” strategy, someone’s rabbits have to be the first to die, and we don’t want it to be yours. Hence, the RWAF advises that all pet rabbits be vaccinated against VHD and their boosters kept up to date.

How can my rabbit catch VHD?

There are lots of ways your rabbits could pick up the virus:

The virus itself if extremely tough and can survive for many months in the environment, and can even resist temperatures of 60 degrees centigrade!

What happens to rabbits if they catch VHD?

Baby rabbits, under about 8 weeks of age, don’t get ill at all. But VHD usually kills older rabbits. They may just die suddenly, with no sign of anything wrong. Or they may get very ill before dying, have difficulty breathing, go off their food, have a high temperature and bleed from the nose and bottom. A few rabbits only get mildly ill and then recover.

Can I prevent my rabbits catching VHD?

Yes! VHD is a preventable disease: there are several steps you can take to protect your rabbit.

Firstly, and most importantly, have your rabbit vaccinated against VHD. Bunnies need to be vaccinated against VHD every year as well as being vaccinated against myxomatosis. Myxomatosis booster vaccinations are needed every 6 to 12 months (depending on the risk of myxi in your area, and your rabbit’s living arrangements) so talk to you vet about a tailor-made vaccination programme for your bunny.

Good hygiene is very important in reducing the risk of disease, so keep hutches/cages very clean. Ensure that vermin and wild birds can't get into outdoor hutches or runs. You might need to use weld-mesh with smaller holes! Make sure there is nothing attract to wild mice and rats to your rabbits: sweep up any spilt food and bedding. Don’t pick green foodstuffs from areas where wild rabbits live, and try to stop wild rabbits from getting into your garden. If this is not feasible, make sure it is impossible for wild visitors to have nose-to-nose contact with your pet rabbit.

Rabbits living indoors (house rabbits) are still at risk from VHD, so they definitely need to be vaccinated with boosters kept up to date.

What vaccines are available?

Cylap was the only VHD vaccine available in the UK between 1997 and early 2007. It is made by Fort Dodge Animal Health and is widely used across Europe and Australia. Cylap can be given as a single dose from 10 weeks of age with a booster every year. In "high risk" situations (for example, a rescue centre in the middle of a VHD outbreak) rabbits can be vaccinated at a younger age, but a second dose will then be required four weeks later.

Lapinject, produced by CEVA Animal Health, became available in the UK in early 2007. It can be given as a single dose from 5 weeks of age with a booster dose every year. Onset of immunity (i.e. the time taken for the vaccine to protect the rabbit from attack by the VHD virus) is 6 days after vaccination.

Details for both of these vaccines can be found on their official data sheets, which the prescribing vet should consult. Cylap & Lapinject are oil-based vaccines, given subcutaneously (under the skin) and occasionally rabbits do develop inflammation at the site of injection. Both are licensed for use in pregnant females.

Just as in other animals, your vet should conduct a thorough health check before vaccinating your rabbit. This is very important because vaccines should only be given to healthy animals – if an animal is already ill or unwell, it may not respond properly to the vaccine.

Cunical, a water-based vaccine, was withdrawn from the UK market in 1997.

Where do I get vaccine from, and how many doses are in a vial?

Are vaccinated rabbits dangerous to unvaccinated ones?

No. VHD vaccines are "killed" vaccines, and cannot cause the disease itself.

I think my rabbit may have died from VHD. What should I do?

Keep away from rabbits belonging to other people and telephone your vet for advice.

If your rabbit has only just died it would be wise to ask your vet to perform a post-mortem examination. If your vet finds changes in body organs suggestive of VHD, further tests can be performed to confirm the diagnosis. Some other conditions can mimic VHD, so it is worth pursuing a definitive diagnosis, particularly if you have other rabbits or are considering another.

If your rabbit died some time ago and you are thinking of getting a new rabbit(s) it is important to thoroughly clean and disinfect all cages and equipment or buy new. Talk to your vet about suitable disinfectants that will kill the virus as not all are powerful enough. Alternatively, adopt a rabbit that has already been fully vaccinated – but make sure it has had a week or two to be fully working!

What about myxomatosis?

Myxomatosis is still around and still dangerous. Your pet rabbit should be vaccinated against both diseases. This usually means two trips to the vets – no combined vaccines are available in the UK, and the RWAF recommends following the manufacturer’s advice to leave a two-week gap between the injections. Some vets will vaccinate against both diseases on the same day in very exceptional circumstances, such as in the face of a disease outbreak, but this is an “off label” use of the UK vaccines.

This information is brought to you by the Rabbit Welfare Fund - the charitable wing of the Rabbit Welfare Association. If you love rabbits, please consider supporting the Rabbit Welfare Fund. You can make a donation, or you may like to join the RWA. The 17.50 adult subscription includes a subscription to "Rabbiting On", a fabulous quarterly magazine packed with health, behaviour and care advice to help you build a wonderful relationship with your bunny - whether s/he lives indoors or out.

© Rabbit Welfare Association/Dr Linda Dykes 2001/2005
© Rabbit Welfare Association/Dr Linda Dykes/ Judith Brown BVM&S MRCVS 2007