The first evidence that properly manufactured feline enteritis vaccine offers longer than one year immunity was published in the early 1990s and since that time we have had a policy at the London Veterinary Clinic of giving boosters less frequently than yearly. Today, we vaccinate and give booster inoculations according to an individual’s life style. These are our general guidelines.

Background Information On Inoculations

Preventing disease through inoculation is a technique that harnesses the body’s natural ability to fight infection. An infectious agent such as a virus or bacteria is modified so that it is no longer infectious but is still similar enough to its unmodified infectious form that when the immune system is exposed to it, the immune system creates antibodies, proteins that attach to and help destroy the specific infectious agent. Vaccines are creating either by killing infectious agents, modifying them so they are still alive but no longer infectious or by taking vital components of them and, through genetic engineering, enslaving bacteria to produce replicas of these parts. Kittens acquire protective antibodies from the milk they suckle from their mothers soon after birth. These temporary antibodies usually last around six to 12 weeks.

Vaccination For Indoor And Outdoor Cats

We vaccinate all indoor and outdoor kittens against feline infectious enteritis and two forms of cat flu, feline herpesvirus-1 (FHV-1) and feline calicivirus (FCV), with two inoculations given three weeks apart, starting as early as eight weeks of age. We follow the suggestions of The American Association of Feline Practitioners and the American Academy of Feline Medicine and give a booster at fifteen months of age and then no more frequently than every three years for feline infectious enteritis, and in general every three years for FCV and FHV-1. Boarding catteries usually require proof of vaccination within the preceding 12 months.

Outdoor cats that meet feral cats are vaccinated against leukemia virus (FeLV) as kittens and again at fifteen months of age. As cats age, the frequency of booster inoculations against FeLV diminishes until in most instances it can safely stop.

Cats traveling under the Pet Travel Scheme are vaccinated against rabies with a three year vaccine. For more information, please go to “Travelling abroad with your pet” in NEWS AND ADVICE

Indoors Or Outdoors?

Most cats we see live indoors but if you have a garden decide when you get your cat whether to let it roam outdoors. The indoor versus outdoor debate has no conclusive answer but there is no denying that outdoor cats, especially in the heart of London, live much shorter lives than indoor ones, not just because of the greater risk of fatal injuries but also because of the array of potentially lethal viruses cats come in contact with when they meet and fight with cats that carry these viruses. Infections from two of these viruses damage the immune system and predispose to the development of lymphoma, the most common tumour cats have. Outdoor risks from transmissible diseases are dramatically reduced through vaccination.

Feline infectious enteritis

This virus causes severe vomiting and diarrhoea, even death especially in kittens. It can survive for prolonged periods in the environment.

Cat ‘flu

Two common viruses, feline herpesvirus (FHV-1) and feline calicivirus (FCV), are spread by close contact with carriers and are responsible for the majority of cases of acute upper respiratory tract disease or ‘cat ‘flu’ that we see. Infection causes mild to severe signs including sneezing, nasal discharge, eye inflammation and discharge, mouth ulcers, sore throat (pharyngitis) and coughing. Pneumonia is a life-threatening complication. Some cats recover fully in a few days. Others take weeks. Some develop permanent damage to the nose or eyes. Vaccination protects a cat from severe illness but does not prevent infection. Even more exasperating, vaccinated cats can still become carriers of the viruses even though they don’t show any signs of disease and pass them on to others.

Feline leukaemia virus

Feline leukemia virus or ‘FeLV’ is a fragile virus transmitted in the saliva through prolonged close contact between cats. Infection usually results in life-long infection and frustratingly most die within three years of being diagnosed with FeLV, usually from an associated illness such as lymphoma or anaemia. While only around one per cent of healthy cats test positive up to 18 per cent of ill cats seen by vets have FeLV. Blood testing for this virus has been very effective in reducing its incidence in purebred cat breeding. FeLV vaccine provides protection for cats at risk although it doesn’t necessarily protect all cats.

Vaccines can have adverse effects

Mild reactions such as pain at the injection site or a low fever for a day are neither unusual nor worrying but more severe adverse reactions to inoculations do sometimes occur. In the largest UK published survey suspected adverse reactions occur in one out of every 15,000 inoculations, usually in cats under six months old. The most common adverse reactions were lameness, temporary injection site reactions and general allergic reactions.

Injection site sarcomas

One rare form of adverse reaction is a localised tumour called a sarcoma. Recent research suggests that the vaccination itself does not cause the development of the sarcoma, but rather this tumour develops in some cats as a result of that individual’s genetic predisposition to develop sarcomas following inflammatory change in soft tissues whatever the cause. Vaccination, other injections, and other forms of trauma may all cause inflammation leading to the growth of a sarcoma. There is no difference in the likelihood of injection site sarcomas for products from different vaccine manufacturers. Other studies have revealed injection site sarcomas can develop after injection of other products including antibiotics to some cats. The true incidence of injection site sarcomas is considerably lower than some of the 1990s estimates suggested but if your cat is one that has localized reactions (heat, swelling, sensitivity) to any injections we recommend keeping all injections to a minimum.

Homeopathic vaccine nosodes don’t work

It would be wonderful if homeopathic protection against transmissible infection worked but challenge studies show that it doesn’t. If you believe in homeopathic nosode treatment, by all means provide it for your cat, but don’t deny it the true protection of primary inoculations.

For more information on feline infections see “Cat germs” in NEWS AND ADVICE