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Abstract. Brazil is the only country endemic for zoonotic visceral leishmaniasis (ZVL) that regularly conducts epidemiologic and prophylactic control programs that involve the treatment of human cases, insect vector control, and the removal of seropositive infected dogs. This report reviews 60 studies reporting data on the efficacy of these recommended control tools and concludes that in Brazil 1) eradication of the disease in Minas Gerais was achieved by the concomitant use of the three control methods, 2) although seropositivity by an immunofluorescent assay is not completely related to infectiousness, the removal of seropositive dogs leads to a significant reduction of canine and human incidence, 3) improvement of the sensitivity of the diagnostic tool used for canine control should optimize the efficacy of control, and 4) although difficult and expensive, the public health dog control campaigns performed in Brazil reduced the incidence of ZVL and should be maintained since treatment of dogs is an unrealistic intervention, both because of its prohibitive cost and relatively poor effectiveness.

RESUMO A leishmaniose visceral no Brasil estava inicialmente associada a áreas rurais, mas devido às diversas alterações no ambiente como, desmatamentos, urbanização e intenso processo migratório, ocorreu a expansão das áreas endêmicas, levando à urbanização da doença, principalmente nas regiõesAs leishmanioses são doenças enzoóticas e zoonóticas causadas por protozoários parasitas, morfologicamente similares, do gênero Leishmania (Kinetoplastida: Trypanosomatidae), podendo acometer o homem 6 .A leishmaniose visceral (LV) vem se tornando um importante problema de Saúde Pública, devido à sua incidência e alta letalidade, não só nas Américas mas na Europa, África, Ásia e Oriente Médio 17 . Nas Américas, a LV ocorre desde o México até a Argentina, sendo que cerca de 90% dos casos humanos descritos são procedentes do Brasil 16 . A LV apresenta amplo espectro epidemiológico no mundo, ocorrendo em vastas áreas tropicais e subtropicais do globo, podendo apresentar-se como zoonose, antroponose ou antropozoonose, estas duas últimas, quando o homem atua como reservatório no ciclo de transmissão do parasito 21 .

The performances of ELISA assays with different antigen preparations, such as Leishmania amazonensis or L. chagasi lysates and the recombinant antigens rK-39 and rK-26, were compared using sera or eluates from dried blood collected on filter paper to detect anti-Leishmania antibodies in dogs from a visceral leishmaniasis-endemic area in 106 (92.2%) were positive in parasitological exams (skin and/or spleen). These animals were compared to healthy animals (n = 25), negative for IFAT at a titre of 1:40 and parasitological exams. The sensitivities of crude and recombinant antigens were similar and remarkably high for both sera and eluates (97-100%). Specificity was higher than 96% for sera and eluates for different antigens, except for L. chagasi antigen using eluates (88%). Concordance values among the tests were higher either for sera or eluates (J = 0.95-1.00). High concordances were observed between sera and eluates tested with different antigens (kappa = 0.93-0.97) . Crude and recombinant antigens identified different clinical phases of canine leishmaniasis. These results show that eluates could be used in canine surveys to identify L. chagasi infection. Recombinant antigens added little when compared to crude antigen in identifying positive dogs. Cross-reactivity with other diseases whose distribution often overlaps VL-endemic areas is a limitation of crude antigen use however. Key words: canine visceral leishmaniasis -Leishmania (Leishmania) chagasi -diagnosis -recombinant antigensVisceral leishmaniasis (VL) is a zoonosis caused by Leishmania (Leishmania) chagasi and transmitted by the phlebotomine sand fly Lutzomyia (Lutzomyia) longipalpis in Brazil. VL occurs in both rural and urban areas and has become a serious public health problem in several large Brazilian cities in recent decades (Arias et al. 1996). Domestic dogs play an important role in VL maintenance in man-made environments by serving as reservoirs of the parasite (Deane & Deane 1962). In Brazil, canine visceral leishmanisis (CVL) prevalence ranges from 1.9 to 35% in endemic areas (Evans et al. 1990, Nunes et al. 1991, França-Silva et al. 2002. The parasite can be isolated by means of tissue biopsies in 40-50% of dogs with positive immunofluorescence titres (Lanotte et al. 1979, Pozio et al. 1981 as well as asymptomatic animals . Consequently, asymptomatic and symptomatic infected dogs are both infective to the sand fly vectors (Molina et al. 1994).Recommended VL control strategies in Brazil involve systematic treatment of human cases, elimination of seropositive dogs and residual spraying of houses and animal shelters with insecticides (Vieira & Coelho 1998 high proportion of asymptomatic dogs, serological methods are essential for CVL diagnosis. Although the immunofluorescent antibody test (IFAT) is the most widespread diagnostic method, cross-reactivity with other diseases and low sensitivity in detecting asymptomatic dogs are the main limitations of this technique. In addition, IFAT is not readily adaptable to large-scale seroepidemiologi...

The evaluation of the efficacy of an immunochemotherapy protocol to treat symptomatic dogs naturally infected with Leishmania chagasi was studied. This clinical trial had the purpose to test the combination of N-methyl meglumine antimoniate (Glucantime and the second generation recombinant vaccine Leish-110f plus the adjuvant MPL-SE to treat the canine leishmaniasis (CanL). Thirty symptomatic naturally infected mongrel dogs were divided into five groups. Animals received standard treatment with Glucantime or treatment with Glucantime Leish-110f + MPL-SEas immunochemotherapy protocol. Additional groups received Leish-110f + MPL-SE only, MPL-SE only, or placebo. Evaluation of haematological, biochemical (renal and hepatic function) and plasmatic proteins, immunological (humoral and cellular immune response) and the parasitological test revealed improvement of the clinical parameters and parasitological cure in dogs in both chemotherapy alone and immunochemotherapy cohorts. However, the immunotherapy and immunochemotherapy cohorts had reduced number of deaths, higher survival probability, and specific cellular reactivity to leishmanial antigens, in comparison with chemotherapy cohort only and control groups (adjuvant alone and placebo). These results support the notion of using well-characterized recombinant vaccine as an adjunct to improve the current chemotherapy of CanL.

A study of the phlebotomine sand fly fauna was carried out in an endemic area of American visceral leishmaniasis (AVL) in the municipality of Porteirinha, in the Brazilian state of Minas Gerais. Captures were performed with CDC light traps in 7 districts, 5 days per month, during 2 consecutive years (January 2000 to December 2001). A total of 3240 sand flies were captured and identified. Sixteen species were found, among which 15 belonged to the genus Lutzomyia and one to the genus Brumptomyia. Lutzomyia longipalpis, a proven vector of AVL, was the predominant species (71.85%) throughout the time period. The interference of climatic factors (temperature, humidity, and rainfall) over the populational dynamics of the sand flies was determined. Statistical analysis of the data showed a significant correlation among the number of phlebotomine sand flies collected, rainfall, and humidity, whereas the effect of temperature was negligible, in that particular region. The amount of collected phlebotomine, the number of human cases, and the prevalence of canine AVL in the districts of Porteirinha are discussed

-Control of canine visceral leishmaniasis (VL) remains a difficult and serious problem mostly because there is no reliable and effective vaccine available to prevent this disease. A mixture of three recombinant leishmanial antigens (TSA, LeIF and LmSTI1) encoded by three genes highly conserved in the Leishmania genus have been shown to induce excellent protection against infection in both murine and simian models of cutaneous leishmaniasis. A human clinical trial with these antigens is currently underway. Because of the high degree of conservation, these antigens might be useful vaccine candidates for VL as well. In the present study, using the dog model of the visceral disease, we evaluated the immunogenicity of these three antigens formulated with two different adjuvants, MPL-SE ® and AdjuPrime ® . The results were compared with a whole parasite vaccine formulated with BCG as the adjuvant. In order to investigate if sensitization with the recombinant antigens would result in recognition of the corresponding native parasite antigens upon infection, the animals were exposed for four weeks after the termination of the immunization protocol with the recombinant antigens to a low number of L. chagasi promastigotes, an etiological agent of VL. Immune response was evaluated by quantitative ELISA in the animal sera before and after exposure

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