When bringing a dog into this country the infectious disease that might spring to mind is rabies. If you’ve done any research into importing dogs, then you will probably know that it is a legal requirement for them to have had the rabies vaccination before entry into the UK. This helps to maintain our country’s rabies-free status, protecting our native animal populations as well as human health too. However, what you may not realise is that imported dogs can carry many other exotic diseases.

Sadly, there is currently no legal requirement for these dogs to be tested or treated for many of these other infections before entering the UK. This not only risks the health of that dog but also has the potential to infect other animals too. Some rescue charities may perform screening tests for these diseases, but this is certainly not the case for all of them. Inexperienced new pet owners often don’t know to ask whether their chosen charity has done any testing, and for what. Also, many less reputable organisations only provide minimal information about the animal they are handing over, with only the vaccination history/passport given and nothing on parasite control or blood tests.

You should take your foreign rescue dog to your vet for a check-up and discuss blood sampling as a screen for underlying diseases. Some of these animals are asymptomatic initially; which means they can seem well when you first pick them up and display no outward signs of ill health, with serious problems only developing later. Depending on which country your dog has originated from, these are the most common diseases that are tested for…


Brucella canis is a bacterium that can be transferred when an infected dog mates. It usually causes issues with the reproductive system. This leads to the birth of weak, sickly, or stillborn puppies as well as problems with conceiving a pregnancy in the first place. Males can become infertile, with enlarged and painful testicles. Other more non-specific signs may include lethargy, loss of libido, lameness, back pain and enlarged lymph nodes.  

Euthanasia is often advised for infected animals. Treatment is not recommended as it can involve prolonged courses of antibiotics which are often unsuccessful at eliminating the issue. The dog poses a risk to other dogs, and even humans


Heartworm, or Dirofilaria immitisis a parasite that mainly affects dogs. It is spread by mosquitos that feed on the blood of an infected animal and then go on to bite another animal. The tiny immature stages of the heartworm are injected into the mosquito’s new host where they travel in the bloodstream to the heart and nearby blood vessels to grow and reproduce.

The most common signs of heartworm infection include a dry cough, lethargy and shortness of breath, which may be more obvious after exercise. Damage to the smaller blood vessels in the body can also occur due to immature heartworms; so kidney and liver damage is a possibility. The extent of the symptoms depends on the number of adult worms present in the dog, obstructing the heart and blood vessels.

Treatment is not always straightforward with complications occurring in some cases.


Leishmania is a disease caused by a type of microscopic parasite called protozoa. The most common protozoa to cause this is known as Leishmania infantum which is spread by sandflies; a type of biting insect (although dog to dog transmission in the absence of sandflies can also happen).

The disease can present in different forms, including visceral which can cause symptoms like fever, lethargy, nosebleeds (epistaxis) weight loss, diarrhoea, vomiting, excessive thirst and joint inflammation. The cutaneous form causes changes in the skin such as hardening of the pads and nose (hyperkeratosis), nodules and lumps appearing and hair loss. Problems may be seen in the dog’s eyes too.

Treatment courses can be long, and many dogs remain carriers with their infections relapsing at a later date. The disease can be fatal in some cases, and it is also zoonotic (meaning people can catch it).


Ehrlichia canis is a rickettsial bacteria transmitted through tick bites. This special type of bacteria only lives inside other cells. In this case, the dog’s monocytes (a type of white blood cell). Infections can be variable, with signs including fever, lethargy, appetite changes, clotting issue, pale gums and lymph node enlargement. Some chronic infections can be difficult to treat, but others may respond to antibiotics.


This disease is caused by a small protozoal parasite which is usually transmitted by the bite of an infected tick, a type of larger external parasite. There are many different species of the babesia parasite. But the most common in dogs are Babesia canis and Babesia gibsoni. This protozoon causes damage to the red blood cells, leading to anaemia. Infected dogs may show symptoms such as fever, lethargy, pale gums, jaundice (yellow gums), elevated heart rate and also issues with blood clotting.

Affected animals may need a blood transfusion depending on how advanced the disease is. Medications including anti-protozoal drugs and antibiotics are used to treat the infection.


We are fortunate enough to live in a country where these diseases are very rare in our pets. But other countries are not necessarily the same. This means if you are importing a dog from abroad there is a real risk that they could be carrying something harmful. This is especially true if they are a rescue dog that has had a poor start, with previously limited use of anti-tick or heartworm products. Even if your dog appears to be well, responsible ownership means getting your new dog screened. The earlier a disease is found the more effectively it may be managed. Speak to your vet for more details about what your pet should be tested for and the costs involved.

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