Which diseases do we vaccinate against?
Parvovirus disease is characterised by weakness and severe bloody vomiting and diarrhoea. Dogs, especially puppies, dehydrate quickly and die due to dehydration and, sometimes, severe blood loss. In puppies under the age of eight weeks the virus can also damage the heart muscle. Parvovirus can be caught directly from other infected dogs, but the virus can also survive for several months in the environment. It can therefore be picked up by a dog just sniffing in the park, for example. Illness usually develops within ten days of being infected.
Intensive treatment is frequently necessary for dogs with parvovirus infection. Unfortunately, even with intensive care, not all dogs can be saved.
Clinical signs in mildly affected dogs include fever, poor appetite, a painful tummy and pale or jaundiced (yellow) gums. More severely affected dogs can develop bleeding and some patients are left with kidney damage. Infected dogs shed the virus with all their body secretions, especially urine and faeces, and may continue to be infectious for some time, even after they have survived the disease. As the virus can live in the environment for several months, it can be picked up by a dog during a normal walk without necessarily meeting an infected animal.
With intensive therapy many dogs, but unfortunately not all, can survive hepatitis.
The virus causing canine hepatitis is different from the human virus, so people cannot become infected with this disease.
Distemper virus can attack almost every organ, so affected dogs can develop a multitude of clinical signs ranging from fever, severe conjunctivitis, pneumonia, vomiting and diarrhoea, to meningitis and encephalitis (inflammation of the brain). Dogs that manage to survive acute distemper are often left with brain damage, leading to tics or seizures (fitting). They may also develop thickening of their paw pads and nose (‘hard-pad disease’) which can be painful. Infected puppies that survive the acute form often have teeth with damaged enamel which leads to early tooth decay. Infected dogs shed the virus with all their body fluids and can continue shedding virus for a long time after surviving the acute disease. Virus particles can also be transmitted through the air.
Intensive treatment is usually necessary for dogs with distemper and they may then survive the initial acute disease. However, further on-going treatment is often necessary to try to control the chronic signs of the disease (seizures or hard-pad disease), which unfortunately is difficult in most cases.
Leptospirosis is the only bacterial disease included in dogs’ vaccine protocols. Several forms of the Leptospira bacterium exist, but all cause liver and kidney disease and often failure of these organs. This disease is a zoonosis, which means that humans can become infected too. In human medicine leptospirosis is known as ‘Weil’s disease’ and there is no vaccination available for humans. Leptospirosis bacteria can survive for a long time in damp or wet surroundings (eg puddles or near rivers) and, as they are also transmitted by small mammals like mice or voles, dogs are potentially at risk on every walk. Many dogs can survive with intensive treatment, but may be left with liver or kidney damage. As infected dogs shed large amounts of Leptospira with their urine, owners are at risk of catching the disease from an infected pet.
Kennel cough is actually not a single disease, but a group of diseases causing very similar clinical signs. Any cough that it transmitted easily to other dogs is called kennel cough. Several ‘bugs’, both bacterial and viral, can cause this problem. Kennel cough vaccine is not included in the routine vaccination protocol, but instead is only given on request, for example when dogs go into kennels or attend shows. In many cases kennel cough is a mild disease, although the cough can last for several weeks. In some dogs, however, especially those with pre-existing heart or lung problems or flat-nosed breeds, it can be more worrying and difficult to treat.
WHEN SHOULD PUPPIES BE VACCINATED?
Puppies generally need two vaccinations given two to four weeks apart (depending on the vaccine used). The first vaccination is usually given when the puppy is about eight weeks old. Full protection starts about seven to ten days after the second vaccination has been given.
The two vaccinations are given to ensure a good immune response resulting in strong protection against the diseases mentioned. It also makes sure that maternal antibodies (antibodies received by the puppy from the mother’s first milk) do not stop the vaccination working. The maternal antibodies give the puppy some protection during the first few weeks of life until its immune system has matured, but unfortunately they also interfere with the response to vaccination. The maternal antibody levels usually start to drop after six weeks and disappear when the puppy is between eight to ten weeks old, leaving the puppy open to infection. Giving two vaccination injections helps to catch the puppy at the times when it begins to need protection and can respond to the vaccine.
Occasionally breeders will request an additional early parvovirus vaccination at six weeks of age. This is done because in a few puppies antibody protection will start to decline already at this age. One reason to vaccinate against parvovirus so early is that at a very young age parvovirus not only affects the bowel system, but also damages the heart muscle. Another reason is that a few dog breeds such as Rottweilers and Dobermans seem to be particularly susceptible to parvovirus and it is advisable to vaccinate them three times as puppies for added protection.
HOW OFTEN SHOULD A DOG BE VACCINATED?
The basic answer is that a dog should be vaccinated again when the level of protection starts to wear off. This can be an individual time period for each dog and also depends on the type of vaccine used. Currently the vaccine manufacturers advise vaccinating against distemper, parvovirus and hepatitis in puppyhood (see above), then at one year of age and every three years thereafter. Leptospirosis and, if necessary, kennel cough, have to be vaccinated against yearly, as the protection does not last very long. This time period is set by manufacturers to ensure that the level of protection stays high.
WHY IS A HEALTH CHECK NECESSARY BEFORE VACCINATION?
The annual health check plays a vital role in the process of vaccination. Because successful vaccination is only possible when the body is able to build up a sufficiently strong immunity against the diseases, it is important that the dog is healthy at the time of vaccination and that the immune system is working properly and is not ‘otherwise engaged’.
The health check prior to vaccinating your dog makes sure this is the case. If we find cause for concern, we will not give the vaccine, but treat the problem we find or, if we cannot make a diagnosis through the clinical examination, we will advise further tests to find out what is going on. Only after we have sorted out the problem will we ask you to come again to have your dog vaccinated.
The annual health check itself is just as important as regular vaccination as this allows us to spot problems early and to give assistance with routine healthcare issues – after all, our patients cannot tell us if there is something bothering them!
In very rare cases dogs are unable to produce a proper vaccine response even when they are healthy.
Should you be at all concerned before or after vaccination, please contact us.