Autoimmune disease, irritable bowel disorders, lupus, thyroid issues, eisonophilic skin disorders, chronic skin disease and allergic dermatitis, not a list any owner wants to pair with their pet, but sadly all of these diseases can be vaccine-related conditions. We can identify them as vaccine related conditions because symptoms are concomitant with vaccination date. We deem this reaction as vaccinosis. And sadly, it is far more prevalent than we could even imagine. At MPN, we see the correlation of vaccination and disease in many of our clients. So let’s take a look at where we started, and how we ended up in such dire straights. The smallpox vaccine was introduced in 1796 after Edward Jenner observed that milkmaids who had previously caught cow pox didn’t catch smallpox. The idea was that exposure to killed or weakened virus/bacteria that cause disease can prime the immune response, but it doesn’t actually make the host sick. So, vaccinations allow the host to develop immunity without having to suffer the disease. To this end, smallpox is now declared eradicated. There is no doubt that vaccination has been progressive in public health concerns, for both humans and pets, but they were never meant to make the host sick. For a number of reasons, the current vaccinations schedule for our pets, is. There is increasing evidence that over-vaccination is associated with the development or aggravation of immune-mediated disorders and chronic diseases in individual pets that are genetically predisposed. This raises a particularly interesting element that has perhaps been missed when developing the blanket vaccination schedules for our pets. Twin studies, in humans have demonstrated there is a clear genetic role in vaccine response. A growing list of genes have been associated with immune related functions critical to immunological response and much data is concluding it is the status of these genes that is key to immune response. Human data is highlighting that this is one of the reasons vaccines can either elicit partial, complete or failure to protect individuals treated under the same conditions. This would also suggest that the opposite is therefore true; gene status could elicit partial or complete adverse reaction, or hopefully failure to demonstrate adverse reaction. Genes are a set of instructions and there are a number of factors that can affect how they are expressed. This is likely understood in the canine world to some extent because most vaccines are advised as safe for healthy dogs but not those with a compromised immune system. So, what constitutes a compromised immune system? The primary role of the immune system in dogs is to protect against foreign invaders, or abnormal cells that invade or attack. The immune system must distinguish between self and non-self. Substances that stimulate a response are antigens. These can be contained within bacteria, viruses or microorganisms or cancer cells. They may also exist on their own, like pollen or food particles. There are three lines of defence, physical barriers, non specific immunity and specific immunity. Physical barriers are the first line of defence, they include the skin, the cornea of the eye and the membranes lining the respiratory, digestive, urinary and reproductive tracts. The key is to keep these barriers unbroken. These barriers are also defended by bacteria and secretions that contain enzymes that can destroy harmful bacteria. Examples include eye tears, secretions in the digestive tract and the microbiome in the gut. Nonspecific immunity should be present at birth; it treats all foreign substances in the same way. Inflammation results in white blood cells travelling into tissues to kill invading organisms and remove injured cells. Specific immunity is acquired and developed as the immune system encounters different antigens, it learns the best way to attack and develops a memory for that specific antigen. It takes time to develop a response, but in future encounters, the response is more rapid. Specific immunity involves the action of lymphocytes (B and T cells), antibodies, antigen presenting cells and cytokines. Most vaccines work by stimulating the development of specific immunity. But the immune system does not always function properly, it can be underactive and overactive. An underactive system puts the animal at risk of infection, but an overactive immune system can attack parts of its body that it misidentifies as being foreign. This is what happens in autoimmune conditions. The immune system can also overreact and produce too many antibodies or other chemicals; these are what we see as hypersensitivity or allergic reactions. Not only do we have to ensure the physical barriers remain healthy, but we also must ensure that responses are just right. We know that genes play a role in this, but so does the environment your dog (exposure to toxins, chemicals and pesticides etc) alongside nutrition. Each cell in every body uses chemical reactions to build some of the materials that it needs, converting substances provided by the diet into other chemicals necessary for normal functioning. This is why the immune system has its own micronutrient (vitamin and mineral) requirements. For example, Vitamin A helps to maintain structural and functional integrity of mucosal cells in innate barriers like the skin and respiratory tract, Vitamin D stimulates immune cell proliferation and cytokine production, helping to protect against infection, B12 has roles in natural killer cell functions just as folate maintains natural killer cells. Many micronutrients play a role in protecting against reactive oxygen species and reactive nitrogen species which are produced when pathogens are killed by immune cells. Findings here So, there are many things that can compromise an immune system, which also informs whether the dog is a candidate for vaccination and indeed subsequent and frequent booster vaccinations. Signs your Dog may have a compromised immune system: Tiredness/lethargy Increased stress levels Digestive issues Slow healing wounds Frequent infections (eyes, ears etc) Delayed growth/development Skin sensitivities/allergies Joint stiffness and disease Other diagnosed disease If your dog is suffering with any pre-existing health conditions, it pays to consider titre testing. No animal should be vaccinated with a compromised immune system.
A global infection of both humans and animals, leptospirosis is on the tip of most owners and dog professional’s tongue. Caused by the pathogen icleptospira spp. it is a major zoonosis, with infection acquired from wild and domestic animals. Canine leptospirosis presents very similarly to the syndromes presented in other species with hepatic, renal and pulmonary ramifications. In short, it’s pretty rough, but vaccine induced immunity is restricted to serologically related serovars and is generally very short-lived; therefore, needing annual revaccination. If there are more than 230 serovars belonging to at least ten pathogenic species, does the vaccine even pose benefits? Or do the risks outweigh them? We are going to look at the science and explore both sides to this story. Fancy coming along for the journey? Leptospirosis is characterised by fever, jaundice, vomiting, diarrhoea, renal failure, haemorrhages and ultimately death. However, for those who recover, they may become asymptomatic renal carriers for extended periods and shed infectious leptospires into the environment. This is a large source of infection, as rats can be carriers but do not show signs of infection. Whilst treated dogs can shed leptospires, so can vaccinated dogs. This raises the first red flag; is this potentially increasing exposure? Most signs of leptospirosis become apparent in the first week after infection; younger dogs, less than 1 year of age tend to get the most severe forms of leptospirosis and 87-100% of infected dogs will have some degree of renal implication. There do appear to be different clinical parameters of the infection: Peracute Disease: super-sudden onset which usually affects younger dogs with an overwhelming exposure. The large amount of toxin causes rapid death before the kidney or liver disease even occurs. Acute Disease and Subacute Disease: this is the classic form which manifests as fever with bruising and bleeding, general muscle pain and painful abdomen from kidney and/or liver disease. There may be jaundice and inflammation in the eyes. Chronic Disease: recurring fevers, chronic hepatitis, chronic kidney disease, uveitis, poor appetite and weight loss. However, leptospira interrogans sensu lato is sensitive to doxycycline which is a readily available antibiotic. Leptospires are cleared from the blood within 24 hours of starting antibiotics. But it does take around 7 days to clear from the urine. Prognosis, depending on organ damage is 80-90% with appropriate treatment. There are, however, other serovars, like the pomona which is associated with more severe disease and in severe kidney cases, dialysis can be required which is often limited. So, whilst treatment is largely effective, if started soon enough, there was clearly enough concern to develop a vaccine. Vaccination against leptospira interrogans sensu lato is available for the seravars canicola, grippotyphosa, pomona and icterohaemorragiae. Some vaccines coverall four serovars, whereas some cover two of the four. This is where you will recognise the common lepto two or four vaccine. Vaccination against canicola and icterohaemorragiae has been traditional for dogs and vaccination overall, has been seen to reduce the severity of the disease, but will not prevent infected dogs from being carriers. Note, it supposedly reduces severity, it doesn’t necessarily prevent occurrence. The leptospirosis vaccine was soon associated with a higher chance of vaccine reactions. This is a result of human research into leptospirosis. In the U.K. in 2014 , over 2000 reports of Novibac L4 adverse reactions have been reported to the VMD (Veterinary Medicine Directive) and around 120 suspected deaths related to vaccinosis. In addition to this, data suggested that the severity of the disease was associated with the intensity of the immune response. In short, the more intense and early the response, the more severe the disease. Findings here If our immune system, and our dog’s, is primed to take out antigens and protect, why does a more intense response seem to make things worse? An intense immune response induces a high level of inflammatory cytokines which can result in severe tissue lesions. Immunity is like the porridge in Goldilocks. It can sometimes be too cold (lacking) and sometimes too hot (overzealous). Ideally, we want it, just right. There are many things that affect immune responses, in the case of lepto, a more intense response was associated with previous infection. Fever was induced by virulent injection in previously immunised rabbits whereas non-immunised rabbits exhibited no fever after injection. So, in this case, the immunised rabbits fared poorer than non-immunised rabbits. See where we might be going with this? So we are vaccinating to potentially reduce, not prevent the severity of infection but here it appears those rabbits immunised, had a more severe reaction to exposure. But, stress, nutrition and the environment can all affect immune responses too. So too, can genes. This can help explain why some animals are more, or less susceptible to pathogens (or vaccines) than others. And explain the age-old statement, but my dog was fine! It therefore raises no eyebrows when reports appear of clinical leptospirosis in numerous dogs when they had previously been vaccinated. You’ll remember this from earlier, when it was deemed to reduce severity, not necessary prevent occurrence. This was however, associated with vaccine type. In short, the dogs were vaccinated against only two of the many pathogenic serovars. So, in walked Lepto 4. But these new vaccines were associated with further increases in vaccine reactions, not limited to local swelling or hypersensitivity, but including cardiac abnormalities. Specifically, heart murmurs appearing between first and second vaccination. Findings here What is particularly interesting in studies exploring the use of lepto 4 vaccines, is that dogs demonstrated antibodies to serovars not vaccinated against. Researchers have therefore concluded that natural exposure (not vaccine exposure) to serovars provide positive titre results. Not only that, but in cases of vaccinations up to 1745 days previously, some dogs still demonstrated antibodies. This raises a question around the need for such frequent booster vaccinations. The take home from this particular study was “seroconversion following vaccination differed considerably among individual dogs.” Yet they still concluded that, “in the light of the high incidence and
A brilliant guide on how to vaccinate safely, here it is in all it’s glory, everything you need to know about taking care of your pet, not over vaccinating, being responsible and taking care of your pet, based on scientific review. Guidelines from the World Small Animal Veterinary Association are at the core of this article and something many vets ignore or don’t know about. UNDERSTANDING VACCINATIONS, IMMUNISATION, TITER TESTING AND WSAVA GUIDELINES The World Small Animal Veterinary Association (WSAVA) is a global veterinary community that bases their guidelines on evidence based veterinarian medicine. These guidelines are to give vets the current scientific advice on the best vaccination concept. In this blog we will be discussing core vaccinations, the difference between vaccinating and immunising and WSAVA guidelines on vaccination protocol and titer testing. Core vaccinations are “parvovirus, hepatitis and distemper” this is the DHP three in one vaccination currently in the UK. The only vaccinations you can give on its own is parvovirus. What is the difference between vaccinating and immunisation? Just because you have vaccinated your dog does not mean that your dog is immunised, when we give a vaccination, we aim to immunise. When a dog is immunised it means that the vaccination has worked and the dog has immunity to the diseases it has been vaccinated against. If you give the last vaccination when your pup is too young, they will still be covered by the mothers maternal immunity and the vaccination will not work/take. Then once the mothers maternal immunity has wained they can be unprotected against those diseases. If you have a dog that is a non responder, it is impossible to immunise them no matter how often you give a vaccination, these dogs will always be susceptible to those diseases. WSAVA guidelines on puppy vaccinations The recommendations are for initial core vaccinations at 6-8wks of age, then every 2/4wks until 16wks of age, then a booster at 6-12 months or a titer test 4wks after the 16wk vaccination, to check if the puppy is immunised. If the pup is immunised, then the guidelines say there is no need for the 6-12 month booster. The difficulty is knowing at what age it is best to give the first vaccination as most pups with be covered by their mothers maternal immunity (MDA). Maternal immunity is passed to the pup through the colostrum in the mother’s milk. Maternal immunity can begin to wain as little as 8 weeks but can last up to 14-16 weeks and for this reason, the WSAVA states, there is “No single primary vaccination policy will therefore cover all situations”. When getting a pup, it is important to know if the mother is immunised, if so the pup will have some maternal immunity. If you vaccinate early and give three vaccinations, you risk over vaccinating your pup but if you wait till later to vaccinate, there is a risk of your pup getting one of the illnesses. It depends on your pups circumstances and what risk you see as the greater. My advice is to base your decision on this. If the pup is hand reared, the pup will not have any maternal immunity therefore the earlier vaccinations would be more beneficial. Waiting to give the last vaccination at 16 weeks is important as this is when the dog is most capable of responding to the vaccination, as all of the mother’s maternal immunity will have wained. How often should core vaccinations “parvovirus, hepatitis and distemper” be given? Often these vaccinations are given annually, this should not happen as the data sheet that comes with the DHP vaccine states “once every three years”. Once every three years, is in most cases, still too frequent for most dogs as the science has proven by serological testing and by challenge that core vaccinations can last up-to the life time of the pet. This is why it is so important to always titer test before giving core vaccinations. WSAVA guidelines state not to be given more frequently than every three years. This does not mean to give every three years, it means they should not ever be given sooner that three years. Please see WSAVA guidelines below. WSAVA GUILDLINES ❗️VACCINATIONS SHOULD NOT BE GIVEN NEEDLESSLY❗️ ❗️CORE VACCINATIONS SHOULD NOT BE GIVEN MORE FREQUENTLY THAN ONCE EVERY THREE YEARS BECAUSE THE DURATION OF IMMUNITY IS MANY YEARS AND MAY BE UP TO THE LIFE TIME OF THE PET❗️ ❗️A DOG THAT HAS RESPONDED TO CORE VACCINATIONS MAINTAINS SOLID IMMUNITY (immunological memory) FOR MANY YEARS IN THE ABSENCE OFANY REPEAT VACCINATIONS❗️ ❗️IT MUST BE REMEMBERED THAT EVEN THE THREE YEAR LICENCE IS A MINIMUM DURATION OF IMMUNITY AND FOR MOST CORE VACCINATIONS THE TRUE DURATION OF IMMUNITY IS LIKELY TO BE CONSIDERABLY LONGER IF NOT LIFELONG❗️ ❗️AN ADOPED ADULT DOG (OR PUPPY OVER 16WKS OF AGE) OF UNKNOWN VACCINATION HISTORY REQUIRES ONLY A SINGLE DOSE OF CORE VACCINATION TO ENGENDER A PROTECTIVE IMMUNE RESPONSE❗️ WSVSA statement on giving more than one core vaccination to an adult dog (or pup over 16 weeks of age and restarting vaccinations is….. ❗️THIS PRACTICE IS UNJUSTIFIED AND IS SIMPLY CONTRARY TO THE FUNDAMENTAL PRINCIPLE OF IMMUNOLOGICAL MEMORY❗️ How does a titer work? To explain titer testing a little more, a titer test is a simple blood test that will look for circulating antibodies in the dogs bloodstream. When you do a titer test, the level of the titer (antibodies) is irrelevant, it doesn’t matter if your dogs titers come back high or low. Any measurable antibodies means the dog has immunity. These titers will go up and down depending what the circumstance is. A high titer doesn’t mean your dog is more immune than a low titer, a high titer can mean one of two things. The dogs immune system has been over stimulated by vaccinations or your dog has just come into contact with a said disease. For example, if there is a parvo outbreak in your area, your dogs
