Liz Buchanan BVSc MRCVS
Keymaster
Hello! In general, over the past few years, vets have transitioned from using L2 vaccine which protects against 2 strains of Leptospirosis to L4, which protects against 4 strains and therefore provides better protection against Leptospirosis. Leptospirosis is being seen in the UK (when I graduated it was incredibly rare but cases have increased dramatically) and all strains are either common in Europe or present in the UK, so this vaccination is generally considered to be a positive thing. The vaccine has been fully tested, with 2 doses given the set distance apart to start it off and then annually after that. However, what may not have been proven, is whether starting a dog off on L2 and then giving L4 (without starting again with the 2 doses X weeks apart thing) makes that vaccine effective. There is no point in selling ineffective vaccines, so when L4 was introduced several years ago now, vets were told to 'start again' for all patients, so that they could be certain that the vaccination was providing adequate protection. These were the vaccine company's recommendations, based on their research, and to be honest proved a minor logistical challenge for all vets at the time because all of this free-of-charge second vaccinating took time (there was a vet shortage in my area), as did all the explaining, because owners had not perceived anything lacking in the dogs' vaccination programme in the first place. It was sometimes hard to explain that if they had noticed something lacking ie their dogs had caught Leptospirosis, then this would have been a sign that the vaccines had been rolled out far too late and many dogs put at risk. The L4 vaccine was rolled out to reduce risk. At first there were some concerns that L4 may have higher than usual side effects but the risk of any dog reactive adversely to Lepto vaccine is still said to be fewer than seven per 10 000 doses.
For most drugs companies I am aware of, the Distemper / Hep / Parvo vaccine is still only required once a year, unless you are late for those.
Obviously it is your decision whether you vaccinate your dog. It is possible to catch Leptospirosis throughout the UK now and only takes one exposure to water contaminated with rat urine, for Leptospirosis to be caught. This could be from a puddle in any urban garden, or from damp soil.
There is a good article in Vethelpdirect blog about this (type leptospirosis into the search bar), explaining that it is almost impossible to risk assess a dogs' lifestyle and find it free of risk from Leptospirosis.
In balance, it is probably worth the short, stressful consultation for a second Leptospirosis vaccine. We always advocate warning your vet in advance if vaccination is likely to be difficult; perhaps they can put you first on the waiting list, so that waiting time is reduced, for example, or have a nurse available to help?
All the best.
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