Exotic Diseases

The term ‘exotic diseases’ refers to diseases that do not occur under normal circumstances in the UK. It is not impossible for these diseases to enter the UK. Dogs who travel overseas with their owners are at risk of being exposed to diseases not found in the UK. There is a rising trend in importing dogs from overseas rescue centres which may have been exposed to, or carry, diseases not found in the UK.

A 2018 study reported that 40% of UK vets have seen cases of rare or new diseases associated with imported pets in the last year, of which Leishmaniasis was the most common.

The pet travel scheme rules state that animals imported to the UK must have a rabies vaccine and tapeworm treatment, but this does not take account for the fact that the animal may be developing another disease for which vaccination would have little or no effect.

Diseases can spread by:

Diseases like rabies, Brucellosis, babesiosis, Echinococcus multiocularis (tapeworm) and leishmaniasis have serious risks to human health as well as dogs.

This will depend on the exact disease. The conditions of most concern include Leishmaniasis, Babesiosis, Rabies, Ehrlichia, Echinococcus tapeworms, Heartworm and Brucellosis.

This is a blood borne parasite spread by blood sucking sand flies which prefer to feed on dogs, especially hunting dogs, outdoor and stray dogs. Sandflies are widespread in the Mediterranean, Africa and the Middle East. There is now solid evidence that in some situations, Leishmania can be transmitted from dog to dog in the absence of sandflies; and some evidence that it can be transmitted directly from dogs to people.

Signs of disease: Skin lesions, lymph node enlargement, fever, vomiting, diarrhoea, eye problems, and kidney disease. Signs only occur in a proportion of dogs, therefore some may be infected without showing signs, and become a ‘reservoir’ of infection. These dogs can aid the spread of the disease by infecting sandflies who bite them. The disease is potentially fatal for dogs and humans.

Diagnosis: blood tests, tissue samples.

Treatment: A combination of drugs such as allopurinol, meglumine, and miltefosine may be used, although these products are not licensed for use in the UK, meaning a special import license is required before they can be legally administered. Drug treatment reduces clinical signs although the animal may always carry the disease, increasing the risk of spread.

This is a blood borne parasite spread by bites from infected ticks. The disease is found across most of mainland Europe, so dogs who travel are at risk of bites from infected ticks. Babesia has been found in dogs in Essex that had not travelled outside the UK in 2016.

Signs of disease: Lethargy, weakness, pale or yellow gums, bleeding disorders. Some dogs may become carriers. The disease may be fatal.

Diagnosis: blood smears.

Treatment: drug therapy with imidocarb, but may have lifelong repeat flareups. Some dogs require blood transfusion.

Rabies is a virus which attacks the spinal cord and brain tissues. It is spread by bites from infected animals. The UK has been officially rabies free since 1922. Diseases like rabies are known as ‘Notifiable Diseases’. This means that there is a government strategy in place to deal with any potential case of rabies, in order to control and prevent spread of the disease, which is also a danger to humans. Dogs imported to the UK must be vaccinated against rabies.

Signs of infection: Agitation, aggression, progressive paralysis of the throat causing foaming at the mouth, disorientation, seizures, coma and death.

Diagnosis: antibody on brain tissue (after death).

Treatment: none – rabies cannot be cured in dogs, and affected animals are euthanased because of the serious infection risk to humans and other animals. In humans there are strict guidelines for rapid treatment known as Post Exposure Prophylaxis.

A bacterial infection spread by bites from infected brown dog ticks, widespread in the USA and found worldwide

Signs of infection: fever, lethargy, abnormal bleeding, swollen lymph nodes, eye problems, brain disease. Infection may recur despite treatment.

Diagnosis: blood tests.

Treatment: several weeks of doxycycline antibiotics. More severe cases may require a blood transfusion. May be a chronic disease.

Widespread in central and eastern Europe, particularly France, Switzerland and Germany. Dogs and foxes release worm eggs in their faeces.

Signs of infection: dogs may be infected by tapeworm and show no outward signs, but tapeworm may cause serious disease in humans.

Diagnosis: faecal screen.

Treatment: this worm is easily in dogs with drugs such as praziquantel.

Caused by foot-long Dirofilariaworms that live in the heart, lungs and blood vessels, leading to heart failure and serious lung disease. Adult worms breed within the dog and produce microscopic offspring. Disease is spread by mosquitoes who take blood meals and pick up the microscopic worms, which are injected into the next animal the mosquito feeds from. Disease is widespread in the USA and worldwide, infection is harboured in wild foxes and wild coyotes.

Signs of infection: coughing, lethargy, intolerance to exercise, reduced appetite and weight loss. May present with signs of heart failure such as a swollen abdomen. Sudden collapse and pale gums can occur, the ‘caval syndrome’ where worms block the arteries near the heart. This requires emergency surgery to remove the blockage, and may be fatal.

Diagnosis: blood tests.

Treatment: prevention is best, monthly prevention with spot on treatments/tablets licensed to kill heartworm larvae, although few of these are authorised in the UK.

Caused by a bacterium, Brucella canis is the most important species for infection in dogs, and is found across continental Europe and worldwide, especially in Canada and the Americas. The bacterium is spread by contact with body fluids, especially when dogs are mating. This is a particular concern for importing stud dogs, who may show few signs. The disease can be passed to humans.

Signs of infection: Most commonly, abortion or other reproductive signs (e.g. discharge from vulva or penis, or swollen and inflammed testicles), although a wide range of other symptoms can also occur, including eye inflammation and blindness, back pain, lameness, swollen lymph nodes, meningitis, and many other problems. Most infected dogs will survive, but usually remain infected for years, or sometimes for life.

Diagnosis: Blood tests for bacteria or their DNA.

Treatment: Long term (many months or years) of antibiotic therapy, and neutering to prevent passing the infection on. In some cases, the government may require the dog to be euthanased to protect human health as this is a notifiable disease.