Canine leishmaniosis is a parasitic disease caused primarily by Leishmania infantum, which is transmitted by the bite of infected female sandflies (mosquito-like insects). When the sandfly bites its host to feed on its blood, it injects the parasite into the host if it is a carrier. Conversely, sandflies become carriers of leishmaniosis by feeding on a sick animal, and dogs are considered the primary reservoir of the parasite. Although transmission to humans through the bite of an infected sandfly remains rare, canine leishmaniosis is a major zoonosis worldwide. The disease occurs on all continents, but is most prevalent in Europe and South America. It is endemic in nearly 50 countries, where it can affect 60-80% of the dog population¹. In southern Europe, nearly 2.5 million dogs are thought to be infected, including 200,000 in France, mainly in the Mediterranean departments.

The course of leishmaniosis in infected dogs is highly variable: some individuals clear the parasite naturally, others are asymptomatic carriers, while others express the disease to varying degrees. When signs of leishmaniosis do appear, they can occur anywhere from 2 months to 8 years after the sandfly bite and take the form of more or less severe skin lesions, with or without internal organ damage. In severe cases, the disease can lead to potentially fatal complications. 

Prevention, Diagnosis and Treatment

There is no definitive treatment for canine leishmaniosis. Even if all signs of the disease disappear, the dog remains a carrier of the parasite. Therefore, a dog with leishmaniosis must be monitored by a veterinarian for the rest of its life to ensure that its internal organs are functioning properly and to check the amount of parasites in its body. Treatment is then adjusted on a case-by-case basis as the disease progresses. Since 2007, Virbac offers an oral treatment solution. Available in Austria, the Netherlands, Switzerland, Greece, Italy, Portugal, Spain, Scandinavia, Brazil and, as of this year, France, it helps to reduce symptoms, control disease progression and improve the dog's quality of life. 

However, given the persistence of the parasite in the body and the associated health risks, the best solution remains prevention. Vaccination, available in certain endemic countries, reduces the risk of developing leishmaniosis, but does not guarantee 100% protection. It is therefore necessary to take the same precautions with vaccinated animals as with unvaccinated ones, by avoiding exposure to infected sandflies. This prevention may include the use of sandfly vector repellents, keeping dogs indoors during periods of high sandfly activity, and using insecticide collars or pipettes as recommended by veterinarians. 

20 years of commitment to reducing canine leishmaniosis worldwide

At Virbac, we've been committed to learning more about and controlling leishmaniosis on a global scale for 20 years. We are developing a global approach that combines research programs, diagnostic solutions, prevention tools, drug treatment and training programs. In 2011, we submitted the first leishmaniosis vaccine for European approval. In 2017, we provided veterinarians with the first canine leishmaniosis treatment approved in Brazil, ending years of reservoir population control to reduce the risk of transmission. We also contribute to the publication of scientific recommendations and publications on leishmaniosis and the dissemination of knowledge about the disease, such as at the World Leishmaniosis Congress. Our teams are also heavily involved in the ALIVE Animal Leishmaniosis International Veterinary Event, which will be held in Malaga in 2022 and in Nice this year.

_{1Baneth et al., 2008}