Leishmaniasis (EV)

Leishmaniasis for everybody

(by Mònica Planas, animal protector and veterinarian, October 2016; corrections by Tracey Thomas).  

Of the hundreds of thousands of abandoned animals from southern Europe, only some will find a caring and loving family in other civilized countries of the continent. People from Germany, Sweden, the Netherlands, Luxemburg, Austria, Great Britain, Switzerland, etc, adopt these poor creatures and offer them a beautiful future. Many of these cats and dogs are healthy, but others are unwell or have a disability of some kind.

Through this article, we wish to provide some information to help explain the parasitic disease leishmaniasis. This is a disease which is only transmited by a certain sandfly in the warm regions of Europe such as the Mediterranean Basin. It is in these regions that we often see incidents of the disease in dogs, and because of this we wish to supply dog-owners from these countries, important and relevant information.

Our aim is to offer a little help to all who care for our animal friends.   

Leishmanias (Leishmania infantum) are protozoans which are unicellular organisms. They are found in southern Europe and thus it is only here that they can infect certain vertebrate animals such as dogs,  rabbits, hares, etc through  the sandfly named Phlebotomus. Normally this Phlebotomus mosquito bites dogs that live or sleep outdoors. The highest incidence of mosquito bites happen at  night particularly around dusk and dawn when the temperatures are at least 16º C : this explains why the leishmaniasis is contagious only in the warmer areas of Europe around the Mediterranean.

Leishmaniasis:

· is NOT contagious from dog to dog

· is NOT contagious from dog to humans

· is ONLY contagious through the sandfly (and maybe from an infected bitch to her pups)

This explains why one need not be afraid to have a dog infected with leishmaniasis, even with children or other dogs at home.

When a dog is infected, the incubation period can be very long. Scientists state that it can last up to 7 years. There are dogs that are resistant and never show symptoms, and others that recover by themselves. There are other dogs who are not resistant to these parasites and therefore become ill, such dogs need to be treated.

Symptoms

The symptoms of leishmaniasis are diverse and can vary from one animal to another. Some exhibiting one or of more of the following:

· Skin infections eg dermatitis, pyoderma, focused or generalized, with or without areas of alopecia

· Ear infection (otitis)

· Swollen lymphnodes (lymphadenopathy)

· Ocular disease eg uveitis, corneal oedema, conjunctivitis, glaucoma

· Joint inflammation (polyarthritis)

· Diarrhoea (bowel inflammation)

· Nervous disorders eg Horner's Syndrome, cramps

· Blood cell, or blood cell count anomalies  

If the disease is not treated, and if the parasites damage the inner organs (kidneys, liver, etc) the dog could:

· vomit

· lose its appetite

· deliver bloody faeces or diarrhoea

· bleed from the nose (epistaxis)

· lose weight

· be tired, apathy

· have pale gums and other mucose membranes

· others.

Diagnosis

Even today diagnosis of leishmaniasis can be difficult because of the varying reliability of the tests used. These are:

I. Indirect tests:

Serologic blood tests:  these measure the existence of antibodies, which may provide evidence of past or current infection but are not 100% reliable.

II. Direct tests: they are more sensitive.

Bone marrow cytology using 40x, 100x microscopy. If any intracellular forms of the parasite ie amastigotes, are seen a definitive diagnosis can be made. However if none are detected using this method, this does not mean they are not present.

PCR-Tests (Polymerase Chain Reaction) performed on a sample of bone marrow, blood, lymphnode-aspirate and/or damaged or infected skin. It looks for the leishmania's DNA. It is considered to be the most sensitive of all tests.

The tests can be done individually or combined with others. The presence of clinical symptoms helps with diagnosis. Nevertheless, it mustn't be forgotten that a dog that is now negative could become positive in the future.

Treatment and prognosis

Nowadays, even with the use of appropriate medicines and  products not all dogs with leishmaniasis will be completely healed and many of them will have to be treated for life. Fortunately the maintenance treatment with alopurinol tablets is not expensive. The dogs infected with leishmaniasis must be under veterinary survey at least every 6 months in the absence of symptoms: blood marrow, blood and urine analyses should be perfomed.

We recommend that the owners of leishmaniasis-infected dogs, look for vets who have a desire to learn about the disease and a wish to fight against it. Many vets do not know this disease or have no interest at all in treating it properly.

There are different treatment protocols to treat dogs with leishmaniasis. Nowadays the most used drugs are the alopurinol tablets and the meglumine antimoniate or Glucantime® injections (to be injected under the skin). The treatment is a bit long but very efficient. We recommend that every owner of a leishmaniasis-infected dog learn how to inject the Glucantime themselves just in case they need to use it any time. Look for advice on how to do it safely and with ease, it is not so difficult.

One of the newest products to treat the leishmaniasis is the Milteforan®. The active substance is named miltefosine. The milteforan is liquid and  is given orally with food for 28 days and the alopurinol tablets are given as well. This medicine is recommended as an alternative to glucantime, in cases for instance where a dog has a problem with either kidney or liver function.

The  prognosis of leishmanasis depends on many factors, but we can say that when a dog has no complications and the blood and urine parameters are right, these dogs can live as long as other dogs that aren't infected with leishmania. Usually, the treated dogs die because of multiple causes eg traffic accidents, heart disorders or neoplasia, and not due to the leishmaniasis. It is mostly in dogs with severe kidney problems which have never been treated or in dogs that have other concomitant disorders besides leishmaniasis, that the disease leads to complications and even the death of the dog.   

Prevention

Prevention is the best way to avoid leishmaniasis!

Nowadays the best prevention against the leishmaniasis is a combination of methods and products:

- let the dogs sleep inside of the house (especially from May to October), when they live in warm countries

- from May to October use a Scalibor® protector band in combination with a spot-on product such as Advantix® when a dog visits or lives in a Mediterranean country.

In the northern areas of Europe no prevention needs to be taken since there is no risk of infection just because the sandfly does NOT live there.   

An illustrated case

Fantasy before -leishmaniasis & sarcoptic mange- (May 2016)

Fantasy after (October 2016)