Бабезиоза при кучетата: кръвен паразит, пренасян от кърлежи

What causes it

Several Babesia species infect dogs. In Europe the most common is Babesia canis, a relatively large parasite carried by the ornate dog tick (Dermacentor reticulatus). This tick lives in many parts of Europe, and the area where Babesia canis is found has grown in recent years. Babesia vogeli is carried by the brown dog tick (Rhipicephalus sanguineus), which is common in southern Europe. The brown dog tick can also live indoors, in homes and kennels.

There are also smaller species, such as Babesia gibsoni and Babesia vulpes. They are less common in most of Europe, and they can be harder to treat.

Once inside the dog, the parasites multiply within red blood cells until the cells break apart. The loss of red blood cells causes anemia. Hemoglobin from the broken cells can turn the urine red or brown, and as the body breaks it down, the gums and eyes may turn yellow.

Как се разпространява

Most dogs catch babesiosis from a tick bite. An infected female tick usually needs to feed for a day or two before it passes on the parasite. Male ticks that have already fed can do it much faster, in one study within hours. This is one reason vets favor tick products that kill or repel ticks quickly.

Less often, Babesia passes directly from dog to dog through blood. This can happen in three ways.

• Bite wounds during fights, thought to be the main route for Babesia gibsoni
• Blood transfusions from an infected donor
• More rarely, from a mother to her puppies before birth

For Babesia canis, the first signs usually appear one to three weeks after infection. Dogs that look healthy can still carry the parasite in their blood. They can pass it on to ticks that bite them, or to other dogs through blood contact.

Признаци, на които да обърнете внимание

Signs range from mild to life-threatening, and they often start suddenly.

• Fever and low energy
• Слаб апетит или отказ от храна
• Pale gums, a sign of anemia
• Yellow gums, skin or whites of the eyes (jaundice)
• Red, brown or very dark urine
• Vomiting
• Weakness when walking or standing

Some dogs have a slower, long-lasting form, with a fever that comes and goes, low energy, anemia and sore muscles or joints. Young dogs tend to become more seriously ill than adults. The signs can look like other illnesses, including other tick-borne diseases, so vets rely on blood tests to confirm the cause.

Кога е спешен случай

Babesiosis can get worse quickly. Contact a veterinarian right away if your dog collapses or is very weak, has very pale or white gums, has yellow gums or eyes, or passes red or brown urine. Fast or difficult breathing, tiny red spots on the gums or skin, and unusual bleeding are also urgent signs. This is especially true after a recent tick bite or time in an area with ticks.

Severe cases can lead to kidney failure, shock and problems with blood clotting. Less often, the lungs or the nervous system are affected. Early treatment gives a dog the best chance. If you are unsure, it is safer to call the clinic than to wait and see.

Как ветеринарите поставят диагнозата и лекуват

Diagnosis starts with the dog's history and a physical exam. Tell the vet about any ticks you found, recent travel, fights with other dogs, and where the dog came from. A blood count often shows anemia and a low platelet count. In a sudden case, the vet may see the parasites inside red blood cells on a blood smear under the microscope.

A PCR test looks for the parasite's genetic material. It is more sensitive than a smear and can show which species is present. Antibody tests are also used, but antibodies take about two weeks to appear, so an early infection can be missed. Where Babesia is common, a positive antibody test may only mean the dog was exposed at some point. In a long-term, low-level infection, the parasites can be hard to find, and the vet may suggest repeat tests.

Treatment usually includes a medicine that acts against the parasite. The choice depends on the species and on the dog's overall condition, and your vet will explain the plan and any side effects. Many dogs also need supportive care, such as fluids, close monitoring in the clinic and sometimes a blood transfusion. When there are no serious complications, dogs with Babesia canis often start to improve within about two days of treatment.

Treatment does not always clear the parasite completely. Some dogs stay carriers without signs, and the illness can come back later, for example if another illness weakens the dog's immune system. A dog that has recovered can also be infected again. Your vet may suggest follow-up checks.

Други домашни любимци и хората

Babesiosis is not known to spread through everyday contact, such as sharing bowls, toys or a bed. If one dog in a home has babesiosis, the other dogs are at risk mainly from the same ticks, so it is sensible to keep every dog in the household on tick control. Brown dog ticks that have settled in a home or kennel may also need treatment of the surroundings. Your vet can advise you.

Many vets advise that dogs who have had babesiosis should not be used as blood donors or for breeding, and that fights with other dogs should be avoided. Babesiosis in cats is only rarely reported in Europe.

The Babesia species that infect dogs are not known to infect people. Human babesiosis does exist, but it is caused by different species. Ticks can carry other diseases, so it makes sense to remove them with a tick tool or fine tweezers and to wash your hands afterward.

How to lower the risk

Tick control is the main way to prevent babesiosis. Your vet can recommend a product that kills or repels ticks and explain how often to use it. In areas where Babesia is common, vets often advise tick protection all year round. It also helps to check your dog for ticks every day after walks, especially around the head, ears, neck, armpits and between the toes, and to remove any you find promptly. For the removal steps and the types of tick products, see our guide to ticks on dogs and cats.

A vaccine against Babesia canis is available in some European countries. It can make the illness milder, but it does not prevent infection, and protection can vary between strains. Vets use it together with tick control. Ask your vet whether it makes sense for your dog and your area.

If you travel with your dog, ask your vet about the tick risk at your destination before you go. Dogs that move from a region where babesiosis is common to one where it is rare can bring the parasite with them.

Why it matters for rescued dogs

Babesiosis is well known in southern and eastern Europe. Studies have found Babesia in dogs in Bulgaria, Serbia, Romania, Croatia and Greece, among other countries. One survey in central-southern Bulgaria found antibodies to Babesia canis in about one in six dogs tested. In Serbia, Babesia canis is the most common cause, and smaller species such as Babesia gibsoni have also been found. Among imported dogs in central Europe, babesiosis is one of the most frequently seen diseases. Dogs that have lived outdoors or on the street are more exposed to ticks and fights, and some carry the parasite without showing signs.

At Paw Squadron, the first stops after every rescue are the vet and a bath. Each animal gets a checkup, deworming and treatment against fleas and other parasites. Before adoption, every animal also gets a checkup, treatment, vaccinations and a microchip.

After your new dog arrives, keep up tick prevention as your vet advises, and book a visit with your local vet in the first weeks. Tell them where the dog came from, because vets in countries where babesiosis is rare may not think of it at once. Ask whether screening for tick-borne diseases makes sense for your dog. If you notice pale gums, dark urine, a fever or sudden weakness, contact a vet quickly and mention the dog's origin.

If you have more questions about a dog's health before or after adoption, our FAQ is a good place to start, and you can find more health guides in PawPedia.