Tularemia hounds could be hidden transmitters of the hare's plague

Hare's plague: Hounds could transmit dangerous infectious disease tularemia

Austrian scientists have found in an investigation that numerous hunting dogs are infected with tularaemia. The infectious disease, which is colloquially referred to as "hare plague", can also be dangerous for humans. So far it is still unclear whether the disease can also be transmitted from dogs to humans.

Rabbit plague can also be dangerous for humans

Tularemia is a bacterial disease caused by the causative agent Francisella tularensis. This can be transmitted by sucking and stinging insects, as well as directly via contaminated hay and infected blood or other liquids. Raw meat of diseased wildlife also carries a high risk of infection by the pathogens. The life-threatening infectious disease, which is colloquially referred to as "hare plague", meets mainly hares and rodents. But humans can also become infected. Researchers from Austria have now found in an investigation that dogs have been infected with it.

Researchers have found that many hunting dogs are infected with tularaemia. The disease, which is colloquially referred to as "rabies" can also be dangerous for humans. (Image: shocky / fotolia.com)

For symptoms to the doctor

Tularemia is a deadly disease for wild animals such as rabbits, wild rabbits or rodents. However, as a zoonotic disease, it also poses a high health risk for humans.

In humans, the infectious disease can be very different, depending on the entry point, for example, flu-like symptoms such as fever, but also skin ulcers, blisters in the mouth and throat, pneumonia or conjunctivitis (conjunctivitis) can occur.

Health professionals recommend seeing a doctor for symptoms such as fever, headache, muscle cramps or nausea and vomiting after coming into contact with wildlife or eating wild game meat.

Relevant frequency of infections confirmed

Although it has been known for some time that dogs can become infected as well, how frequently hounds are infected has hardly been investigated.

Researchers at the "Vetmeduni Vienna" have now confirmed a relevant frequency of infections with a blood test carried out on Austrian dogs and a positive rate of seven percent.

This could also increase the discussion as to whether there is an additional risk of infection for humans behind the mostly asymptomatic animals.

The results of the Austrian researchers were published in the journal "Vector-Borne and Zoonotic Diseases".

Hunting dogs in Austria regularly infected as thought

Since dogs usually show little or no symptoms and a high natural resistance to a small amount of bacteria without secondary diseases, they are hardly considered in studies.

Nevertheless, there are theories that the four-legged friends could serve as an intermediate host and thus as a further contagion reserve.

And especially in hunting dogs, similar to hunters, come directly into contact with infected wild animals, such as when retrieving, the question is justified, how regularly just these four-legged infected with the pathogens.

Scientists at the Research Institute of Wildlife Ecology at the Vetmeduni Vienna have therefore for the first time examined the blood of 80 Austrian hunting dogs from territories in which the tularaemia pathogens occur regularly.

"After two independent analyzes, we identified five dogs as clearly positive," said first author Annika Posautz in a statement.

Thus, it could be shown that the number of dogs in the Austrian areas, in which the rabbit plague is endemic, that is regularly occurring, are more frequently infected.

Risk of infection by infected dogs possible

"The quota of about seven percent makes clear that it can also come regularly to the infection of hunting dogs. As a carrier of the pathogen, even without symptoms, the animals could also be considered as an unexpected carrier, "said Posautz.

But according to the researchers still missing a clear scientific proof.

Factors such as the age at which young dogs may come into contact with contaminated game more frequently for training purposes, however, as well as the question of whether the four-legged friends are a risk of infection for humans, need to be analyzed by further studies.

The blood was tested with two different agglutination tests in order to be able to infer antigens on the surface of the pathogens or antibodies formed by the immune system.

"In these detection methods, one specifically causes a clumping of these features, which thus become visible under the microscope," says the researcher.

"If you suspect a tularemia disease, it is necessary to do more than one of these tests because it can also cross-react with other agents. If all tests are positive, the disease can be clearly confirmed. That was the case with five animals, "explained Posautz. (Ad)