As a profession we all have a duty to promote improvements in animal welfare. Preventative health schemes are key to helping the lives of our patients, and one part of this includes the use of vaccinations.
Posted: 29 May 2019
The most recent PDSA PAW report 2018 highlights the need for this, as currently the level of protection given to pet rabbits in the UK is too low. In the report, we read that;
It’s interesting to note that whilst many rabbit owners are aware of a need need to get their rabbit vaccinated against Myxomatosis, most aren’t aware of the other major threat, Rabbit Haemorrhagic Disease (RHD), despite the emergence over the last few years of the highly infectious RHD2 variant. The PAW report suggests that the main reasons owners don’t get their rabbits vaccinated are;
RHD is an extremely infectious and often fatal condition that affects both wild and domestic rabbits. There are currently two strains in the UK, RHD1 and RHD2. Both are caused by a Calici virus. RHD1 has been present in the UK since 1992 and RHD2 since 2013.
It’s success as a deadly disease is helped by the fact that it’s easily transmitted. Some of the ways the virus is spread include;
For many years, the original strain of this disease, RHD1, was brought under control by the effective use of vaccines, but as the RHD2 emerged it soon became evident that no protection to the new strain from the original RHD1 vaccine was provided. In just a matter of a few months, the new disease became widespread throughout the UK.
The incubation period is very short, sometimes as little as 1-2 days, and unfortunately in many cases, sudden death can occur with no warning. Many vet practices are unaware of a local problem as it develops since owners will often just go ahead and bury the body without asking for help. The virus is also very stable in the environment and can survive for up to 7 months in some situations. It’s also not unusual for it to remain active on clothes and surfaces for at least 3 months.
If you are presented with a case of RHD1, look out for;
This is now the more prevalent disease in the Europe and the UK. All ages of animal are affected, and some breeds seem to be more susceptible than others. The clinical signs of RHD2 are similar to those produced by RHD1 except that they are slower to develop (typically around 5 days). The incubation period for RHD2 is also longer, between 3-9 days, so in these situations the animal will often be infectious to others for much longer compared to RHD1. With RHD2, the mortality rate is much lower, with occasionally around 80% of animals surviving. Survivors of the disease however, tend to have more protracted problems, in particular chronic liver disease. Look for the chronic form of the disease, with animals developing weight loss, jaundice and anorexia. These animals will often be shedding the virus for long periods, as long as 2 months, again helping to spread the disease more successfully.
As RHD1 and RHD2 are highly contagious, it’s vital we do as much as possible to contain the disease. There are no treatments other than supportive care.
With RHD1, the mortality is so high that you’re unlikely to be able to help. However, with RHD2, the longer you can keep an animal supported and alive, the more likely it is to survive.
The good news is that there are some highly effective vaccines available to protect against both RHD1 and RHD2 in the UK, and it’s recommended that all domestic rabbits are immunised from an early age.
In November 2018, the animal health company, Hipra, launched a single-dose vaccine for rabbits. It was the first monovalent vaccine registered in Europe for the prevention of RHD2. The key benefits of the vaccine are;
As has already been mentioned, the Calici viruses are easily spread, which is why the emergence of these two fatal rabbit diseases has been so successful. Containing the virus is essential, both at home and in the practice. Here are some of our top tips on keeping your rabbit patients safe.