Viral haemorrhagic disease (RVHD) is a highly infectious condition that affects domestic rabbits worldwide. This disease is caused by a virus – Calicivirus – and is spread by both direct and indirect contact. This means that transmission can occur either via contact with an affected rabbit and his urine/faeces/secretions, or by contact with contaminated water, food, utensils, clothes, hutches, etc. Furthermore, some insects may also serve as vectors, spreading the disease even further.
Clinical signs of the “classic” RVHD (RVHD1) include fever, lethargy, haemorrhagic discharge from nose and mouth, breathing difficulties, diarrhoea, or sudden death. The incubation period for this virus is very short, and rabbits can die within 12 to 36 hours of infection. In some cases, the course of the disease is slower, and the affected animal’s condition slowly deteriorates until they pass away, usually 1 to 2 weeks after the beginning of clinical signs. A vaccine that protects rabbits from RVHD1 and Myxomatosis has been available in the UK for many years.
Unfortunately, there’s now a new variant of this disease – RVHD2 – which is caused by a new strain of the virus. This new variant is causing several outbreaks in the UK and, sadly, it has been detected in Felixstowe. The RVHD2 is spread in the same ways as RVHD1, but the disease has a slower onset of clinical signs, which can be vague and non-specific: anorexia, lethargy, or just causing the rabbit to be “not quite himself”. It can also cause sudden death, just like with the classic disease, where the rabbits can appear to be fine and then found dead or dying a few hours later.
Vaccines used for the classic strain of RVHD don’t offer protection against this variant, but we do have now a new vaccine that protects rabbits from RVHD2. Although, this new vaccine doesn’t protect against Myxomatosis, so we recommend continuing to vaccinate your rabbit against Myxomatosis, as well as vaccinate him against RVHD1 and RVHD2. This means he will need 2 vaccinations, administered 2 weeks apart from each other. The Myxomatosis+RVHD1 vaccination can be administered to rabbits from 5 weeks of age, while the RVHD2 vaccination can only be administered to animals older than 10 weeks. In low risk areas, an annual booster is sufficient to keep the rabbits safe, but, in areas where RVHD2 cases have been confirmed (like Felixstowe), a 6-monthly booster is recommended.
There’s no treatment available for this disease, so prevention by vaccination is essential!
We recommend keeping your rabbits’ bedding clean and dry, as well as protecting their hutch against insects (by hanging insect repellent strips or using insect mesh netting, e.g.). If you have more pets at home, ensure they’re regularly treated for fleas with a prescription required flea treatment. Furthermore, make sure you prevent your rabbit from coming into contact with wild rabbits and other wildlife that might be carriers of the disease.