Trakia Journal of Sciences, Vol. 6, Suppl.1, 2008 106 Trakia Journal of Sciences, Vol. 6, Suppl. 1, pp 106-115, 2008 Copyright © 2007 Trakia University Available online at: http://www.uni-sz.bg ISSN 1312-1723 ________________________________ ________________________________________ CANINE VISCERAL LEISHMANIOSIS: CURRENT SITUATION I. Tsachev, E. Papadogiannakis 2 , R. Harizanov 3 , I. Zarkov 1 1 Department of Microbiology, Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, Trakia University, Stara Zagora, BULGARIA 2 National School of Public Health, Athens, GREECE 3 National Center of Infectious and Parasitic Diseases, Sofia, BULGARIA ABSTRACT A review on the literature on canine leishmaniasis is performed. The newest contributions to the etiology, epizootology, pathogenesis, clinical manifestation, diagnostics, therapy and prevention of the disease are emphasized. A lot of data are cited, mainly focused on the epidemiology and epizootology of the disease in Bulgaria. Key words: Leishmania infantum , epizootology, clinical manifestation, therapy, prevention, Bulgaria Leishmaniasis is cause by protozoa, belonging to the Leishmania genus that could infect a number of vertebrates, including dogs and men. The clinical criteria for classification of the disease in humans determined three forms of the disease − visceral, cutaneous and mucocutaneous. In dogs, the visceral form that is also accompanied with cutaneous changes, is the commonest and that is why, some authors consider that it is more correct to talk about a generalized leishmaniasis [1,2,3] or also, European canine leishmaniasis [4]. ETIOLOGY. Leishmania are protozoa from the Tripanosomatidae family. The species responsible for the disease are Leishmania donovani infantum (L.infantum) for the Old World and Leishmania donovani chagasi (L.chagasi) for the New World. There are separate L.infantum strains, and the commonest among them is Zymodeme MON- 1 [5]. Leishmania are encountered in two forms − amastigote (non-flagellate, 2-5 x 1.5-3.5 µm) that parasitizes intracellularly in host macrophages and promastigote (flagellate, 12- 25 x 1.5-3.5 µm) that lives in the body of bloodsucking arthropods from the genus Phlebotomus (in the Old World) and the genus Lutzomya (in the New World); the latter comprising about 700 species. Phlebotominae are also called “sand flies”. PREVALENCE. Leishmaniasis is characterized with an endemic distribution pattern. In men, it is found in 88 countries – 72 developing ones, and 13 out of them are among the poorest in the world [6]. In dogs, L.infantum is a great concern in the Mediterranean countries and the Middle East [7-12]. More detailed results from recent surveys show the following picture of seroprevalence: Portugal – 8.5% [13], Cyprus – 1.7-10.0% [8], Albania – 12.9% and one case with L.infantum isolate [14,15], Israel – 3.6-15% [16], Iran – 14.28–21.6% [17], Venezuela – 25% [18], Greece – 3.7-38.8 [19- 21], Italy − 22.1-30.3% [22], Spain − 3-35% [23], France − 10-40 % [4], Bosnia and Herzegovina − 45% [24], Malta − 28.9-52% [25], Turkey − 65-76% [26]. Leishmaniasis is also encountered in non-endemic regions − Austria, Belgium, Germany, Switzerland, Holland, England, Canada and the USA [27- 30]. Studies on canine leishmaniasis in Bulgaria have been performed for the first time in 1941 by Drenovski. Out of 100 examined fogs from Petrich, 81% were seropositive for leishmaniasis. Later, the serological investigations carried out in the same region, showed 13.80% seroprevalence in 160 dogs. Clinical manifestation of the disease was not observed [31]. Further studies in our country have been performed by the team of Dr. Filipov from the National Centre of Infectious