In a BBC report on Tuesday 1st April 2004 it was revealed that more than 30 vets have signed an open letter warning many vaccines for pets given in yearly doses last much longer. In their letter they say that vaccinations for many conditions including distemper, cat flu and parvovirus, last a lot longer than a year and sometimes for life.

The Veterinary Products Committee working group found that there is insufficient information to propose booster intervals other than those recommended by the manufacturer and approved by the regulatory process. However, it emphasised the fact that vaccination should be an individual medical decision made by the vet in consultation with the owner and it recognised that the manufacturers' recommended regimes will be based on a minimum duration of immunity - rather than a maximum.

Intervet, one of the world's largest veterinary drug manufacturers has responded to this open letter with the following statements, which explain the use of vaccines and their importance for your dog's health and the canine population in the UK in general.

David Sutton, a spokesman for Intervet, told BBC Radio 4's Today programme: "We base our recommendations on the science and the science we have tells us that we don't know how long immunity lasts in any individual animal. What we do know is there are some animals that need more frequent vaccination than others and our vaccine recommendations have to be based on taking account of those animals."

The following is a statement on behalf of Intervet UK by Gaynor Hillier.

The low incidence of life threatening diseases in the UK is principally due to dog owners having their pets routinely vaccinated. Vaccination is necessary in order to provide protection against diseases like distemper, hepatitis, parvovirus and leptospirosis. It is the only proven method of protecting dogs and the bottom line is, if we fail to vaccinate our pets, it will only be a matter of time before they become unprotected and suffer serious disease.

Vaccination regimes in this country are undoubtedly moving forward and, contrary to popular belief, the UK is in fact ahead of other countries when it comes to offering products with an extended duration of immunity for certain diseases. In addition to this, we now have conclusive evidence from an independent authority (the Animal Health Trust) that routine vaccination of dogs does not increase the frequency of illness or signs of ill health in dogs.

Despite these recent vaccine developments, however, the need for yearly vaccinations for other diseases, like leptospirosis (which can be passed to humans, and where research has proven that the protection provided by vaccines only lasts for one year) is ever present. A dog will always be at risk of potential exposure to disease if it goes out or even comes into contact with other dogs.

There are so many instances when an animal, and indeed its owner, can be placed at increased risk of exposure to disease. Taking your dog for a walk to the park and allowing it to come into contact with other dogs that may not have been protected against disease is just one such example. It is also important to remember that some of the diseases we protect against can also be passed to humans.

So, if your pet is due a booster, book in to see your vet for a consultation to discuss its future vaccination schedule. As part of the consultation, your vet will also offer a full health check and advice about your individual pet's needs.

Without doubt, science has changed the way we look at vaccination regimes in this country and it is important that you remember the benefits of vaccination and think about the real risks you face if you cease to protect your pet against infectious diseases!

Finally, there have also been concerns regarding the safety of vaccination. The following research results undertaken by the world renowned Animal Health Trust at Newmarket endorses vaccine safety:

An independent and scientifically peer reviewed study presented in the UK for the first time today at the British Small Animal Veterinary Association (BSAVA) Congress in Birmingham has produced the clearest evidence yet that routine vaccination of dogs in the UK does not increase frequency of illness. The study - nicknamed POOCH (Practice Overview of Canine Health) found that their research results clearly demonstrated the absence of any deleterious association between routine vaccination and signs of ill health.

The AHT's research took the form of an epidemiological investigation to evaluate the evidence for any temporal association between vaccination and ill-health in dogs. In total, more than 9,000 postal questionnaires were sent to the owners of a randomly selected population of dogs and just over 4,000 of these were returned and analysed. No temporal association was found between vaccination and ill-health in dogs after adjusting for potential confounders, such as age.

The study population consisted of dogs that had used the services of a veterinary practice within the previous 12 months. The British veterinary practices contacted were randomly selected from a national list. Dogs were then randomly selected from the computer databases of the 28 practices that agreed to participate. On receipt of the owners' completed questionnaires, details of the dogs' vaccination history were confirmed with the veterinary practice.

The survey found that older dogs in general exhibit more signs of illness, including chronic lameness, stiffness and bad breath, and that frequency of these signs increases continuously with age. However, the results demonstrated that recent vaccination (within a period of 3 months) did not increase the signs of ill-health by more than 0.5% and could well actually decrease them by almost 5%.