There are vaccinations available for rabbits for Rabbit hemorrhagic disease which is caused by a calicivirus and is fatal to unvaccinated rabbits. There are a number of strains including one which was introduced in to the wild rabbit population in 2017. Vaccinations should be done every 6 months to keep your rabbits protected. The vaccinations do not, unfortunately, cover every strain of the virus so you also need to take addition steps to keep bunnies protected. The virus affects the internal organs of the rabbit and may result in bleeding although there are often no signs, the rabbit just passes away. Some symptoms you may notice are lethargy, poor appetite, restlessness, fever and bleeding from the nose. There is no cure for the virus.
The virus is spread through urine, faeces and other secretions. It can be contracted from direct contact with other rabbits but also through interaction with an environment or other small animals that have been in contact with the virus. The virus can persist in an environment for up to 3 months.
Some suggestions to reduce the risk of contracting the virus, especially strains that are not covered by the vaccines include: Prevent wild rabbits from entering in to an area frequented by your bunnies, keep your rabbits indoors, avoid contact with other bunnies, wash your hands, shoes and clothing after being in contact with other animals, use a flea medication to control transmission through fleas, avoid contact with flies (a mosquito net can work to prevent flies in the cage). Also, ensure you keep your hutch very clean and remove any food that is not eaten in a 24 hour period.