VHD was first seen in the UK in 1992, and has spread throughout the country. It is common in wild rabbits. The virus is easily spread between rabbits or via contaminated hutches, bedding and food. It can also be carried on other animals’ feet – for example pet dogs could pick up the virus during a country walk and bring it back to an urban garden.
VHD only affects rabbits, and usually only those over 6 weeks old. 90% of infected rabbits develop symptoms which can include loss of appetite, bleeding from the nose and general malaise. Most infected rabbits die, and death is often sudden, without warning. 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.
There are several measures you can take to reduce the risk of infection.
Good hygiene is very important. Keep the hutch very clean. Don’t pick green food from areas where wild rabbits live. Make sure there is nothing to attract wild mice and rats to your rabbits: sweep up any spilt food and bedding.
Rabbits kept outside (especially in garden runs) seem to be at increased risk of catching VHD, so bringing them inside improves their safety (but at the risk of reducing their exercise and fresh air), and make sure wild birds can’t get inside outdoor hutches. Most importantly, your rabbits must be vaccinated against VHD, including houserabbits kept indoors.
Vaccinations against VHD can be given from 10 weeks of age. The immunity produced lasts only a year, and an annual booster vaccination is essential. It is safe to use in pregnant animals. Occasionally, there may be a mild reaction at the injection site, but rabbits very rarely feel poorly afterwards. The vaccine is of the ‘killed’ type and cannot possibly cause disease. Unfortunately, VHD vaccination cannot be done at the same time as myxomatosis vaccination – we usually allow 2 weeks between the doses.
For background, whilst the “classic” RVHD has been present in the UK for decades, variant RHVD (also known as RHVD2 or RHDV variant) was first noted in 2010 in France, and has subsequently been identified in the UK .
This virus has some differences from the classic RVHD. In particularly it may affect rabbits of any age, as opposed to RVHD1, which is rarely if ever seen in rabbits under 8-10 weeks of age. It has also been reported that the variant gives rise to lower mortalities than classical RVHD, this is not necessarily borne out by reports, and this may be thought to be due to be the case due to its phylogenetic placement alongside non-pathogenic strains. Mortality may vary from collection to collection, and possibly from breed to breed.
The only vaccine for rabbits currently available with a UK License is Nobivac Myxo-RHD , which was made available in 2012. Not long after that, the other 3 vaccines against RHVD on the UK market ceased to be available.
This vaccine does not appear to offer protection against RVHD2, and neither do the previous vaccine brands available in the UK. However, RHVD1 and Myxo remain the most significant health threats which can be vaccinated against, and so coverage with this product remains a priority.
Work from Italy and France, however, suggests that, with our reservoir of wild rabbits, we can expect to see RHD2 starting to predominate over RHD1 in the next 5 years or so.
However, there are now 4 vaccines available in the EU which have been licensed or are undergoing licensing for efficacy against RHVD2.
Three of these vaccines (Filavac VHD K C+V, Cunivak RHD and Cunipravac RHD-2 Variant) now have a Special Import or Special Treatment Certificate from the Veterinary Medicines Directorate, on the basis of a clear need to do so given the current disease status.
In particular, Filavac VHD K C+V is available through a UK wholesaler, precluding the need to order it directly from France, but note that the veterinary practice ordering it still needs to obtain an SIC from the VMD. At present, stocks are available through three wholesalers, NVS, Henry Schein, and Centaur, but availability is very variable, and practices are advised to contact wholesalers directly for information on stock availability. There is no reason why other wholesalers cannot stock this product, and practices tied to a specific wholesaler may want to consider encouraging them to stock it.