Leptospirosis is one of the diseases that make up your dog’s “core” vaccine, alongside parvovirus, distemper and infectious hepatitis. Leptospirosis is a water-borne bacterial disease which is spread though contact with the bodily fluids of an infected animal, either through water or soil which has been contaminated with urine from infected animals (such as rats) or through direct contact with blood or urine from an infected animal (such as an infected dog). Rats are the main culprits for spreading the infection, due to their sheer prevalence.
There are several different infectious strains of Leptospira and you may have heard vaccines being called L2 or L4, this refers to how many strains of the bacteria the vaccine will protect against.
L2 vaccines protect against two of the most common strains in the UK, Leptospira canicola and Leptospira icterohaemorrhagiae, whilst L3 protects against Leptospira Grippotyphosa in addition to the previous two and L4 protects against Leptospira Grippotyphosa and Leptospira Australis in addition. These additional strains used to be more common on mainland Europe, but are now just as prevalent here in the UK.
Due to the increased prevalence of Leptospira Grippotyphosa and Leptospira Australis in the UK, the World Small Animal Veterinary Association (WSAVA) now recommends that dogs in the UK are vaccinated with an L4 vaccine. As such, most vaccine manufacturers have now ceased production of L2 and L3 vaccines and will now produce L4 only.
What does this mean for my dog?
At Heathfield Vets we have used the L3 vaccine for a number of years. As this is no longer available and because we want to make sure our patients are fully protected, we will be moving to the L4 vaccine. This means that at your dog’s next vaccination they will need two injections, 4 weeks apart, of the L4 vaccine, in order to be fully vaccinated. The second vaccination will be discounted by 50% for all patients.
I’ve read that the L4 vaccine is dangerous, is this true?
There is a wealth of misinformation online about canine vaccines, particularly leptospirosis. We so often hear from new pet owners who are reluctant to have a particular vaccine because they ‘heard that it can harm dogs’ or their breeder told them it is dangerous. We urge pet owners to read information about vaccines from reputable sources and to consult qualified professionals for advice regarding their concerns. The Veterinary Medicines Directorate, the governing body which receives reports of adverse events due to vaccinations released the following update regarding leptospirosis vaccines in 2023:
“There are a number of vaccines authorised in the UK containing either two (L2) or four (L4) strains of Leptospira. Based on the most recent periodic safety update report data received for each product, the incidence of adverse animal events for all L2 vaccine products combined is 0.016%; for L4 vaccine products this figure is 0.045%.
In other words, the VMD has received fewer than 2 adverse events for L2, and fewer than 5 for L4, for every 10,000 doses sold.
The overall incidence of suspected adverse events for both L2 and L4 vaccine products is therefore considered to be rare.”
The majority of reported signs were allergic type reactions, a well-recognised potential side effect of any vaccine. As with any vaccination or medication, there is a risk of adverse reaction but this risk is minimal and is far outweighed by the benefits of immunisation.
The most common cause of vaccine reaction is due to the Bovine Serum Albumin (BSA) used in vaccines as a stabilising agent. The L4 vaccine we will be using is made by the same manufacturer as our previous L3 vaccine and has the same low level of BSA, so we would not expect any increase in the likelihood of a reaction. The other components that can increase the likelihood of a reaction (usually swelling at the injection site) are ‘adjuvants’, which are added to try and promote a stronger immune response. The vaccine we will be using is non-adjuvanted just like the L3 one was, so again, we would not expect an increased likelihood of reaction.
Does my dog really need the leptospirosis vaccine?
As veterinary professionals, we take the recommendations of the Vaccination Guidelines Group (VGG) of the World Small Animal Veterinary Association (WSAVA) seriously and we trust the clinical data they use. We also base our recommendations on local cases of leptospirosis we have seen, including patients who have contracted the disease having only had an L2 vaccination. We would not recommend a vaccination if we did not believe it was necessary. Leptospirosis is also a zoonotic disease, this mean it can be contracted by humans; by vaccinating your dog to protect them against more strains of leptospirosis, you are not only protecting them, but also yourself and your local community.
Call us on 01435 864422 if you would like more information about the change to the leptospirosis vaccine.
