Canine Leishmaniasis

It is time for me to update my 2001 article on leishmaniasis, a deadly disease for canines. This is because the sand fly is now a vector for the disease in humans (human leishmaniasis) and our dogs (canine leishmaniasis) – not only in bordering states of the Mediterranean, but also in Central European nations including Germany.

In the past, cases of this disease in dogs were almost always traced back to stays in endemic areas, primarily Portugal, Spain, Southern France, Italy, and Greece. When I wrote about this in 2001, veterinarians and dog owners in Central Europe always viewed this as a foreign disease – prevalent mostly among supposedly sick canines imported from the Mediterranean or dogs accompanying tourists.

This aspect has naturally not changed since. However, in the last five years, the warmer climate zone has shifted northwards in Europe, which has extended the habitat range of the sand fly. The annual 10 °C isotherm marks the theoretical threshold for the spread of this disease. Thus the sand fly can now survive in Germany up to the region around Frankfurt/Main and along the Rhine valley to Cologne.

In fact, sand flies have been identified in Germany along the Rhine valley in the state of Baden-Württemberg, up to the Offenburg area, in the North to the Rhine & Main River valleys, through to the Western edge of the black forest, and extending to the Odenwald region in the East.

It is quite likely that the sand fly, the butterfly mosquito, and the disease they cause will continue to spread! Consequently, the assumption is that in the near future leishmaniasis caused by the sand fly in humans and dogs will probably spread further in Central Europe, including the region from Bodensee to Flensburg in Germany.

Sand flies and butterfly mosquitoes, also called phlebotomine sand flies, are found along coastal regions of the world and wetlands. This means their habitat includes all the bordering states of the Mediterranean, Portugal, and in recent years even Switzerland, France, and now Southern Germany. A total of 23 species of sand flies have been identified in the Balearics and other Mediterranean regions of Europe. The behavior of each of these species, however, differs.

Sand flies and butterfly mosquitoes are about 2 millimeters long, sandy colored, with big black eyes, and belong to the genus phlebotomus or lutzomyia. They are direct and indirect vectors for transmission of the leishmania infantum protozoa that leads to a parasitic infection that triggers leishmaniasis. For certain is that these mosquitoes are transmitters of the disease from a dam to its unborn pups.

These small sand flies prefer to live in humid conditions. The phlebotomus mosquito is most active in the spring and fall and early in the morning or at dusk. Only the female mosquito sucks blood, without which reproduction of this species would not be possible.

The female sand fly is only active at night. It prefers dogs as hosts to suck blood. After it infects itself with the leishmania parasite contained in the blood of its host, the parasite remains inside the sand fly’s proboscis to continue its development. The now infectious female passes on the disease by inoculating the next healthy dog with the parasite as it feeds on it for a fresh source of blood. This completes the transmission cycle of the insidious disease.

In most cases, it is too late when the disease is diagnosed, because the symptoms appear several months or up to two years after the animal is infected. The death of young dogs and/or those with a weakened immune system is preprogrammed, since canine leishmaniasis develops slowly and subtly and can soon become fatal. Despite treatment, the disease relapses recurrently and, hence, the focus should be on immune system diagnostics.
After the female phlebotomus mosquito bites its host, the active leishmania parasites circulate in the dog’s blood and lodge themselves in the spleen and liver. The active form of canine leishmaniasis is identified by a drop in the peripheral blood counts for T-lymphocytes and B-lymphocytes (CD4+ and CD21+). At a later stage, the leishmania parasites infest the host’s bone marrow, decompose organs, significantly weaken the immune defense, and eventually even destroy the immune system.
Symptoms

•    Fraying of the ears – several tiny tears along edges of ears
•    Dandruffy skin with scabs forming on tips of the ears, paws, and nose
•    Tiny wounds on the ears
•    Loss of hair on the paws, ulna, around eyes, and ears
•    Conjunctivitis, keratitis (inflammation of the cornea)
•    Inflammation of the eyelids in conjunction with lesions in facial skin 
•    One-sided facial muscular atrophy
•    Nasal hemorrhage (nosebleeds)
•    Depigmentation on lips, nasal speculum, and eyelids.
•    Bouts of fever
•    Anemia
•    Generalized swelling of lymph nodes (ham / hollow of the knee)
•    Listlessness
•    Weight loss
•    Weariness
•    Lacks of appetite (anepithymia)
•    Problems with the stomach
•    Severe diarrhea and vomiting
•    Jaundice
•    Nephritis (kidney infection) caused by accumulation of antigen-antibody complexes
•    Weak hindquarters
•    Prominent bones at elbows, hips, and the zygoma (cheekbone)
•    Overly long and fragile claws
•    Pains in joints with paralysis caused by accumulation of antigen-antibody complexes in joints
•    Dogs in an advanced stage of the diseases stink horribly, which is always a sign of severe impairment of the kidney, liver, and other internal organs. 

Take the dog for a thorough examination, diagnostics, and treatment to a vet as soon as you see any of these symptoms of leishmaniasis. Although there is no vaccination against canine leishmaniasis available in Germany – you can get one in other European countries!

Diagnosis
Lab tests are unavoidable to definitively diagnose canine leishmaniasis. The following analyses are recommended in the literature:

•    A blood test for indirect diagnosis of the disease via an antibody titer, since antibodies appear within 14 to 28 days of an infection. This test determines the hematocrit (HCT) and hemoglobin content in the blood.
•    Microscopic examination of a culture from a bone marrow or lymph node puncture, which is presently the only sure method to identify the disease. 
•    Identification of the leishmania pathogen via a polymerase chain reaction (PCR), which can identify whether leishmania parasites are in the bone marrow or lymph nodes.
•    Protein electrophoresis to determine the albumin/globulin quotient.
•    Tests to determine the CD4+ cell count and the CD4+/CD8+ ratio.
•    A leishmaniasis screening test at the University of Zurich based on the ELISA procedure. For more information about submitting a specimen, visit: www.parasitus.com/forschung/diagnostik/unizh/unizh.html.

Treatment
One should go for a treatment based on the latest research and pursue it conscientiously. The sooner one starts, the better the chances of success. Please remember that the therapy is intensive, lengthy, and costly!

1.    Chemotherapy
•    Use of antimonial drugs like Glucantime and Pentostam will improve the quality of life and increase the lifespan of your dog. These drugs are injected in severe cases, and one of their side-effects is a weakening of the immune system. It is important to accompany this therapy with drugs to protect the liver. A hemostyptic drug may be necessary if another side-effect occurs – nasal hemorrhage and/or bleeding in the vagina. However, this chemotherapy is not a cure.

•    Miltefosine (trade name Impavido) is a new therapy that was found to be efficacious against leishmania infantum in trials with canines. In 2004, Impavido was approved in Germany for the treatment of leishmaniasis. Orally administered Miltefosine can lead to mild to medium-grade gastrointestinal problems, and diarrhea and vomiting is a relatively common side-effect.

2.    Other medications
•    Tablets of Allorpulin seldom have any side-effects, but nausea and diarrhea may occur. Sometimes the dog may show symptoms of an attack of gout. Although rare, administering a similar product, Allopurinol, can lead to urolithiasis and therefore you should feed the dog a low protein diet during the course of the treatment. However, low doses of Allopurinol are safe over a long period.

•    Good results have been achieved with a combination of Allopurinol and Concurat-L. The agent in the latter is Levamisol, a broad-spectrum vermicide (helminthicide). You can self-administer this medication by following the vet’s instructions.
Nevertheless, there is doubt that a few tablets a day can cure leishmaniasis. If your dog is suffering from this disease, do not have your vet put it to sleep to relieve the poor animal from the agony, unless you are absolutely certain that it is incurable. Otherwise such action would be deemed punishable under the Animal Welfare Act.
Prevention
•    The Scalibor dog collar has been on the market for some time now. It contains Deltamethrine, which acts as a repellant not only against bites from infected sand flies and butterfly mosquitoes, but also against tick and flea bites.
•    New products like Advantix from Bayer function as a local repellant that keeps ticks and fleas away from your dog, and also prevents it from being bitten by sand flies and butterfly mosquitoes.

Tips
EARLY DIAGNOSIS BOOSTS THE CHANCES OF A CURE AND EXTENDS YOUR DOG’S LONGEVITY!

•    Even after you have cured your dog of leishmaniasis, it could still be a carrier of the pathogen in its lymph nodes and consequently in the blood. Avoid dog fights at all costs – risk of transmission!
•    Avoid stressful situations for your dog, because the disease could progress.
•    Do not vaccinate or anesthetize your dog if it suffers from leishmaniasis, because these could trigger another attack of the disease. This also means no operations!
•    Ensure that you feed your dog an adequately balanced diet rich in vitamins but low in protein. 
•    Have the vet test your dog’s blood each June and November for leishmaniasis. 
•    You can also send a blood specimen to the University of Zurich for a leishmaniasis check.

Disclaimer
The author has exercised his best knowledge and belief when writing the above articles and content, which are purely for purposes of providing information for visitors. The content of the Web site www.familial-shar-pei-fever.de does not replace professional diagnostics, advice, and treatment by a vet. The information is presented here as accurately as possible and in good faith and trust in the professional integrity of the sources. The author of this site has not evaluated the statements about products and health conditions, whereby any details of diagnostics, therapies, and medications are not intended as recommendations of any kind whatsoever. Never give your dog any medicines or medicinal herbs without consulting your vet. Since the author is not a qualified medical practitioner or vet, he does not accept any liability whatsoever for providing the information herein. 

Referenced literature/sources
•    PARASITUS EX: http://www.parasitus.com/
•    WHO http://search.who.int/search?ie=utf8&site=default_collection&client=WHO&proxystylesheet=WHO&output=xml_no_dtd&oe=utf8&query=leishmaniose&Search=Search
•    www.leishmaniose.de
•    http://hund.meintier.de/Leishmaniose.html
•    VetMed Labor: Diagnostik und Verlaufskontrolle der caninen Leishmaniose (pdf)
•    Gothe, R. (1990) Leishmaniosen des Hundes in Deutschland. Erregerfauna und -biologie, Epidemiologie, Klinik, Pathogenese, Diagnose, Therapie und Prophylaxe (in German). Kleintierpraxis 36, 69-84
•    Gradoni, L., Maroli, M., Gramiccia, M. and Mancianti, F. (1987) Leishmania infantum infection rates in Phlebotomus perniciosus fed on naturally infected dogs under antimonial treatment. Medical and Veterinary Entomology 1, 339-342
•    Gramiccia, M., Gradoni, L., and Orsini, S. (1992) Decreased sensitivity to meglumine antimonate (Glucantime) of Leishmania infantum isolated from dogs after several courses of drug treatment. Annals of Tropical Medicine and Parasitology 86, 613-620
•    Gottstein B, Deplazes P, Arnold P, Mehliz D, Reiter I, Eckert J: Immundiagnose der Leishmaniose des Hundes mit ELISA und Mini-Western-Blot.Schweiz. Arch. Tierheilk. 130:245-262 (1988).
•    Mancianti, F. and Sozzi, S. (1994) Isolation of Leishmania from a newborn puppy. Parassitologia 36 (Suppl. 1), 86 Slappendel, R.J. (1988) Canine leishmaniasis: A review based on 95 cases in the Netherlands. Veterinary Quarterly 10, 1-16
•    Dr. H. Sager & Prof. B. Gottstein (MB.DI.Leish.1995) INSTITUT FÜR PARASITOLOGIE DER VETERINÄRMEDIZINISCHEN UND DER MEDIZINISCHEN FAKULTÄT (IPB) UNIVERSITÄT BERN, (DIRECTOR: PROF. B. GOTTSTEIN) Diagnostics information: canine leishmaniasis


Glashütten, January 2008
Hanspeter Kobold
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