RVHD2 vaccine failures

“We here at the RWAF are aware of a number of posts regarding cases of RVHD2 following vaccination, and, whilst new information is constantly being obtained and updated, we wanted to make a statement.

Firstly, it is REALLY important to obtain that information, and to make sure it is being reported properly, to the correct authorities, and with as much detail as possible. Only then can accurate data be obtained and decisions made. Its possible to hear of the same case from multiple sources and forums, and equally, to not hear about some rabbits at all. So we do urge people to ask their vet to report any concerns about vaccine side effects or failure (or any drug adverse reaction) to both the Veterinary Medicines Directorate, and to the drug/vaccine company directly. Reporting it to the company as well means that they can act more quickly, and may be able to offer advice and assistance. So far, both the VMD and Filavac have monitored the situation and not found higher than expected numbers of vaccine failures.

Secondly, it is important to realise that no vaccine offers 100% protection, and that sensible biosecurity measures should also be employed, especially after cases of RVHD2 have been suspected or confirmed in an area. And sadly some of those unprotected rabbits will succumb to the disease, even with a protective dose value of 90% for Filavac and sufficient antibody titre of ≥70% for Eravac.
Currently only about 14% of UK domestic rabbits are vaccinated against RVHD2, and that means that the level of protection in the community, or “herd immunity” is poor, making spread of the disease rapid and easy for the virus.Most rabbits (85%) have been vaccinated using Filavac, and so most vaccine failures reported online have been associated with this vaccine.

While we are aware that vaccine failures have been reported, we would urge owners not to stop vaccinating their rabbits, as the current vaccines are the best level of protection we have available. Please continue to report any problems, via your vets, to the VMD and the vaccine manufacturers.

Richard Saunders BVSc DZooMed MRCVS European Veterinary Specialist in Zoo Health Management

RWAF Vet Specialist Adviser

Adverse reactions to drugs

On occasions, some animals can respond badly to a medication. This may be a one off in that individual, or due to a unique or rare combination of circumstances, but it may be something that, whilst uncommon, happens in enough animals to suggest modifying the drug, the dose, or the use of the drug in certain circumstances, or in extreme cases, advice not to use a product at all, or even withdraw it. Note that a vaccine failing to protect an animal from that disease counts as an “adverse reaction”. The only way the licensing authorities and drug companies can make such a judgement is with sufficient information from those vets and owners encountering problems. This is always best done through your vet, as they will have all the information the company needs, and will be able to ensure that any relevant data is made available. If for some reason this is not possible, it is possible for owners to submit the adverse reactions form. A compromise might be for owners to download the form and request that their vet complete the technical sections. The suspected adverse reactions form can be found on the Veterinary Medicines Directorate website at: http://www.vmd.defra.gov.uk/adversereactionreporting/Product.aspx?SARType=Animal