Updated Dec 2016.
RVHD1 and RVHD2
This article will provide a concise overview of Rabbit Hemorrhagic Viral Disease, its characteristics, locations, testing methods and some of the preventative steps that can be taken.
Rabbit Viral Haemorrhagic Disease 1 is a type of Calicivirus, has been in Europe for many decades or even centuries and affects both wild and domestic rabbits. There are a few different pathogenic strains of the virus but until recently, RVHD1 was thought to be the only type in the UK.
RVHD2 differs in a few key ways as it is unaffected by age and has a longer illness phase with different clinical symptoms. It is also thought to have a lower mortality rate. Little research has been done on RVHD2 and it is highly likely that cases are under reported.
Both viruses are potentially very easily spread and can live in the environment for a long time (RVHD2 up to 200 days in laboratory conditions) Insects, wildlife and scavengers can spread it as well as direct contact with an infected rabbit. Fomites such as bedding, wild plants, shoes and clothing can also carry the virus to new areas. It is currently unknown if biting insects can spread RVHD2.
Due to it being so easily transported, the spread of RVHD can be very quick and strict biosecurity is recommended as well as vaccination.
The current UK vaccine, Nobivac Myxo-RHD offers protection against RVHD1 but is unlikely to offer any for RVHD2 as this virus is antigenically and genetically different from RVHD1. It is recommended that a second vaccination be given to cover RVHD2 and there are a few options:
- Eravac has been licensed in the UK for use in ‘fattening’ rabbits. This is an oil based drug with no research showing the possible long term effects and there is currently no recommended vaccination schedule.
- Cunivak RHD is currently out of stock and Cunipravac can be ordered via a special import certificate however it is only available in large multi dose bottles.
- Filavac RHD K C+V is available to order from most UK wholesalers and is administered annually or 6 monthly (if considered to be a high risk patient or area). It is vital that the rabbits are still vaccinated with the Nobivac Myxo-RHD as the Filavac vaccine does not give any protection against myxomatosis, however standard immunology advice is to leave at least a 2 week gap between the different vaccinations.
It is important to research all options and discuss with your vet / client. The safety and efficacy of using any other vaccine alongside the Nobivac Myxo RHD has not been studied.
It is not recommended to carry out en-mass vaccination clinics as this could potentially increase the risk of disease spread due to the way RVHD is transmitted.
Testing and Reporting
Its important to consider RVHD2 as a differential diagnosis when dealing with a sick rabbit that doesnt seem to respond to treatment and no obvious reason for the illness is found. PCR testing is now available for live rabbits via the Batt Laboratories in Coventry. For sudden deaths, post mortem liver samples can also be sent here or to the Moredun Research Institute.
Wherever possible, please send samples to either laboratory via the methods outlined on their websites. Please also consider reporting all suspicious deaths to the Rabbit Welfare Association and Fund as their Veterinary Advisor is monitoring the spread of this disease.
Good husbandry is paramount and sick rabbits should be barrier nursed. Enhanced cleaning, disinfection and quarantine protocols can be implemented in practice and with owners. Anigene HLD4V is a veterinary grade product that is believed to be effective against RVHD when used at a concentration of 1:50 for soiled conditions.
It is vital to be aware of the risks associated with attending events such as rabbit shows, petting zoos and even rescues. Environmental insect controls should also be in place as it is still unknown if RVHD2 can be spread via insects. Care should also be taken when considering feeding handpicked wild plants.
Keeping Up To Date
You can also visit the Rabbit Welfare Association’s website as they will always have the most up to date and factually correct info.
Lastly, Rabbit Specialist Vet Francis Harcourt Brown (retired) has information about the disease on her website.
Be wary of other reports and anecdotal stories doing the rounds as they may not be factually accurate. Also, please contact your own vet asap so they are fully aware of the new RVHD2 strain and that they are stocking and advertising the new vaccine to help fight this. We need owners to insist all their vets order in the vaccine to get as many rabbits as possible protected against this fatal disease.
Please know how to keep your rabbits safe and spread the word!
RVHD and Myxomatosis are diseases found throughout the UK and can be fatal to un-vaccinated rabbits. Both outdoor AND indoor rabbits are at risk. RVHD in particular is highly infectious and contagious. It is an air borne virus that can be spread by direct and indirect contact with infected rabbits, food bowls, hutches and even the soles of your shoes. For example – if you, your dog or cat has walked on ground where a VHD infected rabbit has been, you can carry it on your clothes or shoes, your other pets can carry it on fur or feet. The virus can survive in the environment for a long time and can survive cold temperatures far better than you might expect.
PLEASE SEE THE MOST UP TO DATE POST RE VACCINE OPTIONS!
A hot cross bun is not a happy one!
Most of us humans cant wait for the weather to brighten up and bask in the glow of Mr Sunshine. However, imagine doing that whilst wearing a fur coat and not being able to cool down via sweating…doesn’t sound like much fun does it?
Rabbits can easily suffer from heatstroke and this can be fatal. Ideally they need to be kept in an area with a constant temperature of between 10 – 20 degrees celcius (50 – 68 degrees Fahrenheit). They do not cope well with sudden temperature changes and anything above 22 degrees celcius can cause heatstroke.
It is highly recommended that all owners purchase a thermometer that records the maximum and minimum temperatures. Place this in the rabbits main living / sleeping area (make sure its up high safely away from inquisitive bunny teeth!) and check it throughout the day. You will soon see that hutches and closed in areas become significantly hotter than the outside air.
Hutch temperatures can become dangerously high and one recent study shows that they can easily reach highs of 40 degrees celcius within just a few hours – this is like cooking your rabbit 🙁 It can even become far too hot for them when they are in the shade or on a cloudy day.
PLEASE SEEK VETERINARY ADVICE URGENTLY IF YOU SUSPECT YOUR RABBIT IS SUFFERING FROM HEATSTROKE.
Its vital that you understand the signs of distress and heatstroke in rabbits as this is an emergency condition that needs veterinary attention. If your rabbit seems lethargic, off food, is panting, wobbly when moving, dribbling or generally acting weird then CALL THE VETS! Warmer weather also brings a higher risk of Flystrike so make sure you are extra vigilant about checking your bunnies bottoms and cleaning out the enclosure more than usual.
There are quite a few ways of making sure your rabbits (and guinea pigs) stay nice and cool in warmer weather (see the poster for some top tips). The MOST important is that their whole area is in complete shade and that they have constant access to their run from their hutch / shed / cage etc. This allows them to move around and seek out cooler areas. It also allows much better ventilation of their living space.
Icepods made by Scratch and Newton are fab and provide a nice, safe way of keeping small furries cool. Simply pop them in the freezer overnight and then wrap in a tea towel. Place inside the bunnies area and it will release cold air around it. The bunnies dont tend to lay on it directly, but it helps keep the temperature a little lower in that area. You can achieve the same effect by 3/4 filling a large bottle with water and freezing. This still needs wrapping in a tea towel (to prevent any frost burns) but will defrost a lot quicker than the icepods. It is also more of a chew risk once thawed.
You can also get specialist cage fans that are battery operated and can really help keep the air flowing through the enclosure. They can be used indoors and outdoors and just need something to hang on. Never point these directly at the rabbit if it has no way of getting away from it. many rabbits will choose to come and sit in front of it for some time if they feel hot. Never place cooling items in front of, or pointing at their food, hay or water as this could prevent them wanting to eat and drink.
It is not recommended to freeze fruit or veg and feed as it is thought that the very cold temperatures of this can upset the gut and induce stasis or mild tummy ache.
Marble / granite / ceramic tiles can be placed inside the rabbits enclosures (make sure there are no sharp edges) as these stay cool for some time and the bunnies can lay on them. These can also be popped in the freezer for a couple of hours before use for an extra blast of coldness (no longer though as they may crack). And an old towel can be misted with water and frozen for another chill out mat.
Be sure to offer more water sources than usual and try to offer a water bowl as well as a bottle. Rabbits often prefer to drink from a bowl and bottles can leak / break / get stuck and then the rabbit is denied access to vital water. Always offer more than one water source as a back up and refresh twice a day.
For more tips on keeping bunnies cool, check out the following website links: