INTRODUCTION
American cutaneous leishmaniasis (ACL) has traditionally been characterized as a zoonotic disease, primarily affecting males who are occupationally exposed to sylvatic transmission cycles. However, the epidemiologic pattern of transmission of ACL has changed and been accompanied by an unprecedented increase in the number of cases. Evidence of peridomestic and domestic transmission has been reported in at least nine countries in Central and South America.1–11 Factors contributing to this transition are multiple, but generally associated with urbanization and alteration of ecosystems where the transmission occurs.12
Deforestation and replacement of primary forests by plantations has been frequently associated with the domestication of transmission of ACL. Replacement of primary forests with coffee plantations has coincided with the domestic transmission of Leishmania (Viannia) panamensis in the Pacific coast provinces of Esmeraldas and Pichincha in Ecuador7 and with a peridomestic outbreak of L. (V.) braziliensis in Colombia.11
Alteration of ecosystems has led to changes in the distribution and/or density of sand flies, reservoirs and Leishmania, and in their interactions. Explosive increases in sand fly populations,13 movement of sylvatic vectors to peridomestic settings, and expansion of vector competence for other Leishmania species, even subgenera,14,15 have been reported in Latin America. Although sylvatic mammals continue to be regarded as the principal reservoirs, in some domestic settings dogs have been implicated as a source of infection.10,16–25
Previous studies have reported the geographic distribution and frequency of the etiologic agents of cutaneous leishmaniasis (CL) in Colombia.26–30 Although these studies could be expected to show selection bias related to the origin of patients diagnosed, L. (V.) panamensis consistently predominates (54–80% of cases), followed by L. (V.) braziliensis (10–30%), with other species being infrequent: L. (V.) guyanensis (1–3%), L. (L.) amazonensis (2%), and L. (L.) mexicana (1–5%). Leishmania (V.) braziliensis has been and continues to be widely distributed throughout Colombia, whereas L. panamensis predominates in the northern and southwestern regions and more recently has emerged in the southeastern region.27 Leishmania (V.) guyanensis has been reported only from the southeastern region of Colombia in the Amazon River basin, and L. (L.) mexicana has only been reported from five departments that are located in separate regions of the country.
In Colombia, domestic and peridomestic transmission has been described for L. (V.) panamensis and L. (V.) braziliensis.11,31–34 The importance of domestic transmission is underscored by the high proportion of women and children affected by the disease in leishmaniasis-endemic regions. Leishmania (V.) guyanensis, a characteristically sylvatic species,35,36 has not been previously reported in the domestic setting in Latin America.
Since 2003, the communities of southern Tolima, Colombia, where less than 10 cases per year were reported prior to this date, have been experiencing the largest epidemic ever recorded in Colombia. The epidemic peaked between 2003 and 2004 in the municipality of Chaparral (2,800 cases) and then spread to adjacent municipalities where cases continue to be reported. The high proportion of women and children (30%) and predominance of the endophagic vector Lutzomyia longiflocosa37 indicate that transmission has an important intradomiciliary or peridomestic component. The present study was undertaken to identify the etiologic agent of this peridomestic epidemic and its relationship with Leishmania spp. transmitted in Colombia and neighboring countries.
MATERIALS AND METHODS
Isolation of Leishmania.
Leishmania were isolated from patients with a diagnosis of CL within the framework of the local leishmaniasis control programs in the municipality of Chaparral, Tolima during the peak of the epidemic in 2004, and in the municipalities of Chaparral, Ortega, and Rovira during 2006. Lesion aspirates were obtained as part of the regular diagnostic procedures for parasitologic diagnosis, as well as for identification of Leishmania species. Three of the isolates were obtained by the Colombian National Institutes of Health during investigations conducted in Chaparral in 2004. The procedures for isolation and cultivation of parasites have been reported.38 Basic demographic and clinical information was obtained during consultation for diagnosis. All patients with parasitologic diagnosis of CL were referred for treatment with Glucantime® (Aventis Pharma, Sao Pablo, Brazil) (20 mg of Sb/kg/day for 20 days) or Impavido® (Zentaris, Bordeaux, France) (2.5 mg/kg/day for 28 days) by the leishmaniasis program personnel.
Study sites.
The municipalities of Chaparral, Rovira, and Ortega are located in southern Tolima, on the western range of the Colombian Andes. Chaparral, the municipality where the epidemic started, is located at 3°43′37″N, 75°29′14″W, and Ortega and Rovira are located at 3°56′ 20″N, 75°13′27″W and 3°56′20″N, 75°13′27″W, respectively. The altitudes of the three sites range between 600 and 2000 meters above sea level and the average temperature is approximately 21°C. The region consists mainly of intervened dry tropical rain forests and the principal economic activities are agriculture (coffee, maize, beans) and cattle farming.
Identification of Leishmania species.
Leishmania isolates were initially characterized by an indirect immunofluorescent antibody test using a panel of monoclonal antibodies.39–41 Isolates that could not be identified to the species level with monoclonal antibodies were analyzed using isoenzyme electrophoresis in cellulose acetate42–44 for five enzymes that enable discrimination of species of the Viannia subgenus: (nucleoside hydrolase [NH, E.C.3.2.2.2.], phosphoglucomutase [PGM, E.C.2.7.5.1.], phosphogluconate dehydrogenase [6PGD, E.C.1.1.1.44], glucose-6-phosphate dehydrogenase [G6PD, E.C.1.1.1.49.], and superoxide dismutase [SOD, E.C.1.15.1.1.]). The conditions for electrophoretic analysis of polymorphisms of these enzymes have been described.44 The following World Health Organization (WHO) reference strains were included in the characterization of patient isolates: L. (V.) panamensis (MAN/PA/1971/LS94), L. (V.) braziliensis (MAN/BR/1975/M2903), L. (V.) guyanensis (MAN/BR/1975/M4147), and L. (L.) amazonensis (VEC/BR/1967/PH8).
Data analysis.
The age and sex distribution of patients was described. Serodemes were identified on the basis of patterns of reactivity with the panel of Viannia subgenus and species-specific monoclonal antibodies as described for Colombian strains.27 Similarly, zymodemes were identified according to electrophoretic polymorphisms of five enzymes used to discriminate species.43,44
Ethical considerations.
The use of specimens and clinical data for this study was reviewed and approved by the Institutional Review Board at Centro Internacional de Entrenamiento e Investigaciones Médicas (CIDEIM) (Cali, Colombia).
RESULTS
Cultures of lesion aspirates were performed for 102 patients with cutaneous lesions suggestive of CL. A total of 56 strains were isolated from the same number of patients with CL from three municipalities in Tolima. Six isolates were obtained in 2004, at the peak of the epidemic, and the rest were obtained in 2006. Patients had been infected in Chaparral (9), Ortega (19) and Rovira (28), three of the municipalities that have reported cases throughout the outbreak.
All but three of the isolates (94.6%) were identified as L. (V.) guyanensis by isoenzyme analysis. Three (5.4%) isolates were identified as L. (V.) panamensis by monoclonal antibodies. These three strains had been isolated by personnel of the Colombian National Institutes of Health from adult patients in Chaparral in 2004, and sent to CIDEIM for confirmation of species identity.
Phenotypic variation.
Serodemes.
None of the L. (V.) guyanensis strains were reactive with the species-specific B19 antibody for L. (V.) guyanensis under the conditions used. Three reactivity profiles with the monoclonal antibody panel for the Viannia subgenus were observed for the strains of this species from patients in the epidemic focus in Tolima. These corresponded with serodemes 3B (33 strains), 7 (2 strains), and 8 (18 strains) previously described by Saravia and others27 (Table 1). All but 2 of the strains of L. (V.) guyanensis displayed the L. Viannia subgenus epitope recognized by the B2 monoclonal antibody, and 33 of 53 also expressed the epitope recognized by the B12 monoclonal antibody. Viannia subgenus and species-specific epitopes were undetectable in two strains of L. (V.) guyanensis from Tolima. The three strains of L. (V.) panamensis presented the same reactivity pattern, which corresponded to serodeme 1.
Zymodemes.
All 53 L. (V.) guyanensis strains were identified by isoenzyme analysis. Notably, the population of L. (V.) guyanensis that causes disease in the human population of Tolima was found to be homogeneous and pertained to a single zymodeme identical to that of the WHO reference strain M4147 (Figure 1). The three L. (V.) panamensis strains were identical and pertained to Colombian zymodeme 2.3.
Age distribution and clinical characteristics of patients.
A total of 32.0% (17 of 53) patients from whom L. guayanensis was isolated were children less than 15 years of age, and 47.1% (25 of 53) were female (Figure 2). Although this sample is not representative because of possible selection bias, the observed age and sex distribution closely resembles that of the population affected by the epidemic over the two-year period in 2004–2006, during which 34% (964 of 2,834) of the patients were children less than 15 years of age and 40% (1,134 of 2,834) were female. Leishmania (V.) panamensis was isolated from two females and one male who were 17, 20 and 39 years of age, respectively. All patients in which isolation was attempted presented localized cutaneous lesions.
DISCUSSION
Leishmania (V.) guyanensis transmission in Colombia, to our knowledge, has not been reported in regions outside the Amazon region including the eastern plains26–28 (Figure 3B) or within the peridomestic setting. Therefore, the results of this study provide further evidence of the changing epidemiologic patterns of transmission of different species of Leishmania in the New World1–10 and in Colombia in particular.
The age and sex distribution of cases reported during the southern Tolima epidemic is consistent with domestic/peridomestic transmission. The high proportion of females (40%) and children (34%) contrasts with the exclusive prevalence among occupationally exposed males in cases detected at CIDEIM prior to this epidemic (between 1980 and 2004 L. guyanensis was isolated from 26 males between 16 and 56 years of age) and with the high proportion of males (82%) 11–57 years of age in a clinical study of patients who had acquired infection with L. guyanensis in the State of Amazonas, Brazil.45 The demographic characteristics of the Tolima epidemic and of CL patients in this study suggest that transmission is taking place in the peridomicile or intradomicile, rather than in the sylvatic context. Domestic and peridomestic transmission of CL had been described and documented for L. (V.) panamensis, L. (V.) braziliensis, L (V.) peruviana,1–10 and L. (L.) amazonensis.14 Concomitantly with the present report, a study conducted in a national park in the Amazonian lowlands of the Department of Cochabamba, Bolivia, reported the sylvatic vector Lutzomyia shawi in the peridomestic and domestic settings and the intradomicile. An hsp70 polymerase chain reaction–restriction fragment length polymorphism detected L. (V.) braziliensis in 4 of 67 pools from 30–39 female Lu. shawi and L.(V.) guyanensis in 1 of 67 pools. Leishmania (V.) braziliensis also predominated among human cases from whom isolates were obtained, which is consistent with sympatric peridomestic transmission of these two species of the Viannia subgenus, and possibly L. lainsoni, in areas of Amazonian rain forest.46
The distribution of L. (V.) guyanensis in South America is largely confined to the Amazon region (Figure 3A), although some cases have been reported in northern Argentina47 and in the Andes of Ecuador and Peru. In Colombia, the known distribution is limited to the Amazonian lowlands and to the eastern plains26–28 (Figure 3B). A search of the clinical database of CIDEIM showed that 24 of the 26 L. (V.) guyanensis cases diagnosed at CIDEIM in years prior to this epidemic had originated in municipalities in the sub-Andean region in southwestern Colombia (Figure 3B), a finding that differs from the rest of the cases reported, which were from the lowlands of the Amazon region.26–28 The corresponding patients were working-age males who had acquired the disease while temporarily working in the area (military personnel and farmers), and thus are likely to have been affected by the sylvatic transmission cycle. Nevertheless, these sub-Andean municipalities are located at altitudes ranging from 1,000 to 2,000 meters above sea level, which are considerably higher than the sites where L. (V.) guyanensis is usually transmitted (0–1,000 meters above sea level), but similar to the altitude of the site of the Tolima epidemic. These observations suggest the expansion of the distribution of L. guyanensis from the previously reported foci in the lowlands of the Amazon region of Colombia, to the sub-Andean region and then to the Magdalena river valley in southern Tolima (Figure 3).
The principal (Lu. umbratilis) and secondary (Lu. anduzei and Lu. whitmani) vectors associated with L. (V.) guyanensis transmission are prevalent in undisturbed primary forests36 in the Amazon region of South America (Figure 3A).48,49 Among the reported vectors, only Lu. umbratilis has been found in Colombia. If one considers that the ecoepidemiologic characteristics of the site of the epidemic, which consist primarily of dry tropical forest ranging between 1,000 and 2,000 meters above sea level, are strikingly different from the primary tropical rain forests of lower altitudes where the vector is usually found, transmission of L. (V.) guyanensis during the southern Tolima epidemic was likely caused by a different sand fly species.
Studies conducted by Pardo and others in Chaparral, the municipality where most cases have been reported, implicate Lu. longiflocosa as the most probable vector at this epidemic site.37 This study identified three antropophilic species (Lu. longiflocosa, 81.7%, n = 235; Lu. columbiana, 3.4%; and Lu. nuneztovari, 2.1%), but Lu. longiflocosa was considered the most likely vector not only because of its relative abundance and predominance but because it was found inside 41.7% (n = 46) of the houses sampled.37 Lutzomyia longiflocosa was also implicated as the most probable vector in three recent CL epidemic foci, in Huila, Norte de Santander, and Southern Tolima, which are located in the sub-Andean region of Colombia.50,51 Therefore, this species is considered to be the most important vector in this ecologic setting. Unfortunately, the Leishmania species responsible for these outbreaks were not identified.
Lutzomyia longiflocosa has not previously been implicated as a vector of L. (V.) guyanensis either in nature or experimentally. Santamaria and others experimentally infected Lu. longiflocosa with L. (V.) braziliensis and transmitted this infection to an experimental host.52 However, experimental infection has yet to be attempted for L. (V.) guyanensis.
The homogeneity of the isoenzyme phenotype of the strains of L (V.) guyanensis isolated from patients in Tolima, their identity with the WHO reference strain for L. (V.) guyanensis originating in the Brazilian Amazon region, and prior documentation of the presence of this zymodeme in the Amazon region of Colombia suggest that the L. (V.) guyanensis population transmitted in Tolima was from the Colombian Amazon region. Migration of human populations or domestic animals exposed to transmission in the Amazon region of Colombia could have introduced this species to Tolima. At least two other zymodemes of L. (V.) guyanensis have been identified among strains from the Colombian Amazon.44 Antigenic variability in the population of L. (V.) guyanensis transmitted in Tolima was apparent in the reactivity patterns of the strains with species- and subgenus-specific monoclonal antibodies (Table 1). The non-reactivity of L. guyanensis in Colombia with the species-specific B19 monoclonal antibody and two of the three serodemes (3b and 8) observed among L. (V.) guyanensis strains from Tolima had been previously reported among L. (V.) guyanensis strains from the Amazon region that pertain to this zymodeme.27
Zymodeme 2.3 of L. (V.) panamensis strains isolated in Tolima corresponds with that found to predominate among strains from the southern Pacific coast region of Colombia (Patia and Mira river basins).44 Emergence of this zymodeme of L. (V.) panamensis on the eastern side of the Andean mountain range is consistent with introduction by migration of infected reservoirs. The fact that the three cases with L. (V.) panamensis infection were all adults and resided in localities where L. (V.) guyanensis was subsequently found to be transmitted raises the question of whether these were autochthonous cases. Conversely, the conditions that favored extensive transmission in an area where leishmaniasis had only sporadically been reported may have led to transmission of more than one Leishmania species. Sporadic cases of L. (V.) panamensis infection occurred within an outbreak of L. (V.) braziliensis transmission in Dagua, a periurban setting in the Pacific coast region of Colombia in the late 1980s.11
Based on these findings, we conclude that L. (V.) guyanensis is the most probable etiologic agent of the largest epidemic of CL in Colombia. The magnitude of the Chaparral epidemic demonstrates the adaptability of transmission to changing ecologic conditions and the potential for sylvatic Leishmania species to be rapidly disseminated within the peridomestic setting. Furthermore, in view of the variable clinical response of patients with CL caused by different species to available antileishmanial drugs45,53–55 and uncertainty of the clinical response of patients infected with L. guyanensis in Colombia to available therapeutic options, the findings of this study are relevant to control programs based on case identification and treatment.
Reactivity of Leishmania isolates from Tolima, Colombia, with subgenus- and species-specific monoclonal antibodies*
| Reactivity with monoclonal antibodies § | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Antibody specificity† | Serodeme ‡ | L. (V.) p. B11 | L. (V.) b . B16 | L . ( V .) b B18 | L. (V .) g . B19 | L. (V.) B2 | L. (V.) p ./L. (V.) b B21 | L. (V .) b ./L . (V .) g B12 | L . ( V p./L. ( V .) .) b B4 | L. (V.) p./L. (V.) b./L . (V.) c. B8 | Total strains |
| * L. (V.) p. = Leishmania (Viannia) panamensis; L. (V.) b. = L. (V.) braziliensis; L. (V.) g. = L. (V.) guyanensis; L. (V.) c. = L. (V.) colombiensis. | |||||||||||
| † L. (V.) p. = L. panamensis (MHOM/PA/71/LS94); L. (V.) b. = L. braziliensis (MHOM/BR/75/M2903); L. (V.) g. = L. guyanensis (MHOM/BR/75/M4147); L.(V.) sp. = L. Viannia subgenus. | |||||||||||
| ‡ Saravia and others.27 | |||||||||||
| § ++ = intense fluorescence (100%); − = no fluorescence; + = well-defined fluorescence. | |||||||||||
| Reference strains of L. Viannia | |||||||||||
| LS94, L. (V.) p. | 1 | ++ | − | − | − | ++ | ++ | − | ++ | − | − |
| M2903, L. (V) b. | 2 | − | ++ | ++ | − | ++ | ++ | ++ | − | − | − |
| M4147, L. (V.) g. | 3 | − | − | − | + | + | − | ++ | − | − | − |
| Tolima patient isolates | |||||||||||
| L. (V.) p. | 1 | ++ | − | − | − | ++ | ++ | - | ++ | + | 3 |
| L. (V.) sp. | 3B | − | − | − | − | ++ | − | ++ | − | − | 33 |
| L. (V.) sp. | 8 | − | − | − | − | + | − | − | − | − | 18 |
| Not reactive | 7 | − | − | − | − | − | − | − | − | − | 2 |
| Total | 56 | ||||||||||
Enzyme polymorphisms for World Health Organization reference strains of Leishmania (Viannia) species, L. (Leishmania) amazonensis, and representative strains from the three municipalities of the Tolima focus (Ortega, Rovira, and Chaparral) for enzymes discriminating species of the Viannia subgenus. SOD = superoxide dismutase; NH = nucleoside hydrolase; G6PD = glucose-6-phosphate dehydrogenase; PGM = phosphoglucomutase; 6PGD = phosphogluconate dehydrogenase.
Citation: The American Journal of Tropical Medicine and Hygiene Am J Trop Med Hyg 78, 2; 10.4269/ajtmh.2008.78.276
Enzyme polymorphisms for World Health Organization reference strains of Leishmania (Viannia) species, L. (Leishmania) amazonensis, and representative strains from the three municipalities of the Tolima focus (Ortega, Rovira, and Chaparral) for enzymes discriminating species of the Viannia subgenus. SOD = superoxide dismutase; NH = nucleoside hydrolase; G6PD = glucose-6-phosphate dehydrogenase; PGM = phosphoglucomutase; 6PGD = phosphogluconate dehydrogenase.
Citation: The American Journal of Tropical Medicine and Hygiene Am J Trop Med Hyg 78, 2; 10.4269/ajtmh.2008.78.276
Enzyme polymorphisms for World Health Organization reference strains of Leishmania (Viannia) species, L. (Leishmania) amazonensis, and representative strains from the three municipalities of the Tolima focus (Ortega, Rovira, and Chaparral) for enzymes discriminating species of the Viannia subgenus. SOD = superoxide dismutase; NH = nucleoside hydrolase; G6PD = glucose-6-phosphate dehydrogenase; PGM = phosphoglucomutase; 6PGD = phosphogluconate dehydrogenase.
Citation: The American Journal of Tropical Medicine and Hygiene Am J Trop Med Hyg 78, 2; 10.4269/ajtmh.2008.78.276
Age distribution of 53 patients with cutaneous leishmaniasis caused by Leishmania guyanensis from Tolima (2004–2006).
Citation: The American Journal of Tropical Medicine and Hygiene Am J Trop Med Hyg 78, 2; 10.4269/ajtmh.2008.78.276
Age distribution of 53 patients with cutaneous leishmaniasis caused by Leishmania guyanensis from Tolima (2004–2006).
Citation: The American Journal of Tropical Medicine and Hygiene Am J Trop Med Hyg 78, 2; 10.4269/ajtmh.2008.78.276
Age distribution of 53 patients with cutaneous leishmaniasis caused by Leishmania guyanensis from Tolima (2004–2006).
Citation: The American Journal of Tropical Medicine and Hygiene Am J Trop Med Hyg 78, 2; 10.4269/ajtmh.2008.78.276
A, Current reported distribution of Leishmania (Viannia) guyanensis and its principal vector Lutzomyia umbratilis in South America.27,28,46–48,56–64 B, Distribution of L. (V.) guyanensis and Lu. umbratilis in Colombia, according to published and unpublished data (Colombian National Institutes of Health). C, Map of Tolima showing the municipalities affected by the epidemic and locations where Leishmania strains isolated and identified in this study were obtained. Rov = Rovira; Ort = Ortega; San = San Antonio; Cha = Chaparral; Pla = Planadas.
Citation: The American Journal of Tropical Medicine and Hygiene Am J Trop Med Hyg 78, 2; 10.4269/ajtmh.2008.78.276
A, Current reported distribution of Leishmania (Viannia) guyanensis and its principal vector Lutzomyia umbratilis in South America.27,28,46–48,56–64 B, Distribution of L. (V.) guyanensis and Lu. umbratilis in Colombia, according to published and unpublished data (Colombian National Institutes of Health). C, Map of Tolima showing the municipalities affected by the epidemic and locations where Leishmania strains isolated and identified in this study were obtained. Rov = Rovira; Ort = Ortega; San = San Antonio; Cha = Chaparral; Pla = Planadas.
Citation: The American Journal of Tropical Medicine and Hygiene Am J Trop Med Hyg 78, 2; 10.4269/ajtmh.2008.78.276
A, Current reported distribution of Leishmania (Viannia) guyanensis and its principal vector Lutzomyia umbratilis in South America.27,28,46–48,56–64 B, Distribution of L. (V.) guyanensis and Lu. umbratilis in Colombia, according to published and unpublished data (Colombian National Institutes of Health). C, Map of Tolima showing the municipalities affected by the epidemic and locations where Leishmania strains isolated and identified in this study were obtained. Rov = Rovira; Ort = Ortega; San = San Antonio; Cha = Chaparral; Pla = Planadas.
Citation: The American Journal of Tropical Medicine and Hygiene Am J Trop Med Hyg 78, 2; 10.4269/ajtmh.2008.78.276
Address correspondence to Nancy G. Saravia, Centro Internacional de Entrenamiento e Investigaciones Medicas, Avenida 1 Norte No. 3-03, AA 5390, Cali, Colombia. E-mail: saravian@cideim.org.co
Authors’ addresses: Isabel Rodríguez-Barraquer, Rafael Góngora, Martín Prager, Robinson Pacheco, Adriana Navas, Maria Consuelo Miranda, and Nancy G. Saravia, Centro Internacional de Entrenamiento e Investigaciones Medicas, Avenida 1 Norte No. 3-03, AA 5390, Cali, Colombia, E-mails: irodriguez@cideim.org.co, rafael_gongora@cideim.org.co, mprager@cideim.org.co, rpacheco@cideim.org.co, amanzu@cideim.org.co, clinico@cideim.org.co, and saravian@cideim.org.co. Luz Mery Montero, Hospital San Juan Bautista de Chaparral, Calle 11 con Carrera 9 y 10, Chaparral, Tolima, Colombia, E-mail: monteroamaya66@gmail.com. Cristina Ferro, Instituto Nacional de Salud, Avenida Calle 26 No. 51-20, Zona 6 CAN Bogotá, DC, Colombia, E-mail: crisferro@yahoo.com.
Acknowledgments: We thank the Secretaría de Salud del Tolima and personnel from the Leishmaniasis Control Program of the Hospital San Juan Bautista de Chaparral, in particular, Boris Sánchez, Rafael Montaña, and Lina Mora for their help in obtaining isolates and data from clinical histories. We also thank the Instituto Nacional de Salud (Rubén Santiago Nicholls and Martha Ayala) for providing isolates.
Financial support: This study was supported in part by the National Institutes of Health, Division of Microbiology and Infectious Diseases, International Collaboration in Infectious Disease Research Program grant AI065866-3.
REFERENCES
- 1↑
Salomon O, Sosa Estani S, Gomez A, Segura E, 1992. Sandflies associated with a tegumentary leishmaniasis focus in Salta, Argentina. Mem Inst Oswaldo Cruz 87 :S223.
- 2
Le Pont F, Mouchet J, Desjeux P, 1989. Leishmaniasis in Bolivia–VI. Observations on Lutzomyia nuneztovari anglesi Le Pont & Desjeux, 1984 the presumed vector of tegumentary leishmaniasis in the Yungas focus. Mem Inst Oswaldo Cruz 84 :277–278.
- 3
Rangel EF, de Souza NA, Wermelinger ED, Barbosa AF, 1984. Natural infection of Lutzomyia intermedia Lutz & Neiva, 1912, in an endemic area of visceral leishmaniasis of Rio de Janeiro. Mem Inst Oswaldo Cruz 79 :395–396.
- 4
de Queiroz RG, Vasconcelos Ide A, Vasconcelos AW, Pessoa FA, de Sousa RN, David JR, 1994. Cutaneous leishmaniasis in Ceara state in northeastern Brazil: incrimination of Lutzomyia whitmani (Diptera: Psychodidae) as a vector of Leishmania braziliensis in baturite municipality. Am J Trop Med Hyg 50 :693–698.
- 5
Zeledon R, Murillo J, Gutierrez H, 1985. Flebótomos antropófilos y leishmaniasis cutánea en Costa Rica. Bol Oficina Sanit Panam 99 :163–171.
- 6
Herrero M, Rojas J, Jimenez A, Zeledon R, Pereira R, Gutierrez H, 1992. Phlebotomine sandflies associated with human houses in an endemic area for cutaneous leishmaniasis in Costa Rica. Wijeyaratne P, Goodman T, Espinal C, eds. Leishmaniasis Control Strategies: A Critical Evaluation of International Development Research Centre (IDRC) Supported Research. Proceedings of an International Workshop. Ottawa, Ontario, Canada: International Development Research Centre Press, 229–241.
- 7↑
Mouchet J, Le Pont F, Leon R, Echeverria R, Guderian RH, 1994. Leishmaniasis in Ecuador. 5. Leishmaniasis and anthropization on the Pacific coast. Ann Soc Belg Med Trop 74 :35–41.
- 8
Christensen HA, Fairchild GB, Herrer A, Johnson CM, Young DG, de Vasquez AM, 1983. The ecology of cutaneous leishmaniasis in the Republic of Panama. J Med Entomol 20 :463–484.
- 9
Lainson R, 1989. Demographic changes and their influence on the epidemiology of the American leishmaniasis. Service M, ed. Demography of Vector-Borne Disease. Boca Raton, FL: CRC Press, 85–106.
- 10↑
Reithinger R, Davies CR, 1999. Is the domestic dog (Canis familiaris) a reservoir host of American cutaneous leishmaniasis? A critical review of the current evidence. Am J Trop Med Hyg 61 :530–541.
- 11↑
Montoya J, Jaramillo C, Palma G, Gomez T, Segura I, Travi B, 1990. Report of an epidemic outbreak of tegumentary leishmaniasis in a coffee-growing area of Colombia. Mem Inst Oswaldo Cruz 85 :119–121.
- 12↑
Desjeux P, 2002. Urbanization: an increasing risk factor for leishmaniasis. Wkly Epidemiol Rec 77 :365–370.
- 13↑
Gutierrez de Oliveira A, Bianchi Galati E, de Oliveira O, de Oliveira G, Cabello Espindola I, Cavalheiros Dorval M, Peç anha R, 2006. Abundance of Lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae) and urban transmission of visceral leishmaniasis in Campo Grande, state of Mato Grosso do Sul, Brazil. Mem Inst Oswaldo Cruz 101 :869–874.
- 14↑
Martinez E, Le Pont F, Torrez M, Telleria J, Vargas F, Munoz M, de Doncker S, Dujardin JC, Dujardin JP, 1998. A new focus of cutaneous leishmaniasis due to Leishmania amazonensis in a Sub Andean region of Bolivia. Acta Trop 71 :97–106.
- 15↑
Martinez E, Le Pont F, Torrez M, Telleria J, Vargas F, Dujardin JC, Dujardin JP, 1999. Lutzomyia nuneztovari anglesi (Le Pont & Desjeux, 1984) as a vector of Leishmania amazonensis in a sub-Andean leishmaniasis focus of Bolivia. Am J Trop Med Hyg 61 :846–849.
- 16↑
Bonfante-Garrido R, Morillo N, Torres R, 1981. Leishmaniasis cutánea canina en Venezuela. Bol Of Sanit Panam 91 :161–165.
- 17
Falqueto A, Coura J, Barros G, Grimaldi G, Sessa P, Jesús A, 1986. Participação do cão no ciclo de transmissão da leishmaniose tegumentar no município de Viana, Estado o Espírito Santo, Brasil. Mem Inst Oswaldo Cruz 81 :155–163.
- 18
Falqueto A, Sessa P, Varejao J, Barros G, Momen H, Grimaldi JG, 1991. Leishmaniasis due to Leishmania braziliensis in Espírito Santo State, Brazil. Further evidence on the role of dogs as a reservoir of infection for humans. Mem Inst Oswaldo Cruz 86 :499–500.
- 19
Aguilar CM, Rangel EF, Garcia L, Fernandez E, Momen H, Grimaldi Filho G, De Vargas Z, 1989. Zoonotic cutaneous leishmaniasis due to Leishmania (Viannia) braziliensis associated with domestic animals in Venezuela and Brazil. Mem Inst Oswaldo Cruz 84 :19–28.
- 20
Desjeux P, 1991. Information on the Epidemiology and Control of the Leishmaniases by Country and Territory. Geneva: World Health Organization. WHO/LEISH/91.30: 35–47.
- 21
Reithinger R, Espinoza JC, Courtenay O, Davies CR, 2003. Evaluation of PCR as a diagnostic mass-screening tool to detect Leishmania (Viannia) spp. in domestic dogs (Canis familiaris). J Clin Microbiol 41 :1486–1493.
- 22
Reithinger R, Espinoza JC, Davies CR, 2003. The transmission dynamics of canine American cutaneous leishmaniasis in Huanuco, Peru. Am J Trop Med Hyg 69 :473–480.
- 23
Padilla AM, Marco JD, Diosque P, Segura MA, Mora MC, Fernandez MM, Malchiodi EL, Basombrio MA, 2002. Canine infection and the possible role of dogs in the transmission of American tegumentary leishmaniosis in Salta, Argentina. Vet Parasitol 110 :1–10.
- 24
Hernández D, Rojas E, Scorza J, Jorquera A, 2006. Infectividad del perro (Canis familiaris) para Lutzomyia youngi en Trujillo, Venezuela. Biomedica (Bogota) 26 :242–248.
- 25↑
Travi B, 2006. Leishmania (Viannia) braziliensis infection in two Colombian dogs: a note on infectivity for sand flies and response to treatment. Biomedica (Bogota) 26 :249–253.
- 26↑
Corredor A, Kreutzer RD, Tesh RB, Boshell J, Palau MT, Caceres E, Duque S, Pelaez D, Rodriguez G, Nichols S, 1990. Distribution and etiology of leishmaniasis in Colombia. Am J Trop Med Hyg 42 :206–214.
- 27↑
Saravia NG, Weigle K, Navas C, Segura I, Valderrama L, Valencia AZ, Escorcia B, McMahon-Pratt D, 2002. Heterogeneity, geographic distribution, and pathogenicity of serodemes of Leishmania viannia in Colombia. Am J Trop Med Hyg 66 :738–744.
- 28↑
Ovalle CE, Porras L, Rey M, Rios M, Camargo YC, 2006. Geographic distribution of Leishmania species isolated from patients at the National Institute of Dermatology Federico Lleras Acosta E.S.E., 1995–2005. Biomedica (Bogota) 26 (Suppl 1):145–151.
- 29
Rodríguez G, Corredor A, Cáceres E, Cassiano G, Arroyo C, Palau M, 1985. Leishmaniasis difusa. Biomedica (Bogota) 5 :95–111.
- 30↑
Sierra D, Ochoa M, Calle JI, Garcia G, Colorado D, Velez ID, 2006. Leishmania (Leishmania) mexicana in the village of San Matias, municipality of Gomez Plata, North West of Antioquia, Colombia. Biomedica (Bogota) 26 (Suppl 1):232–235.
- 31↑
Morales A, Corredor A, Caceres E, Ibagos A, Rodriguez C, 1981. Aislamiento de tres cepas de Leishmania a partir de Lu. trapidoi en Colombia. Biomedica (Bogota) 1 :198–207.
- 32
Alexander B, Usma MC, Cadena H, Quesada BL, Solarte Y, Roa W, Montoya J, Jaramillo C, Travi BL, 1995. Phlebotomine sandflies associated with a focus of cutaneous leishmaniasis in Valle del Cauca, Colombia. Med Vet Entomol 9 :273–278.
- 33
Munoz G, Davies CR, 2006. Leishmania panamensis transmission in the domestic environment: the results of a prospective epidemiological survey in Santander, Colombia. Biomedica (Bogota) 26 (Suppl 1):131–144.
- 34↑
Santamaria E, Ponce N, Zipa Y, Ferro C, 2006. Presence of infected vectors of Leishmania (V.) panamensis within dwellings in two endemic foci in the foothill of the middle Magdalena valley, western Boyaca, Colombia. Biomedica (Bogota) 26 (Suppl 1):82–94.
- 35↑
Lainson R, Shaw JJ, Silveira FT, de Souza AA, Braga RR, Ishikawa EA, 1994. The dermal leishmaniases of Brazil, with special reference to the eco-epidemiology of the disease in Amazonia. Mem Inst Oswaldo Cruz 89 :435–443.
- 36↑
Ready P, Lainson R, Shaw J, Ward R, 1986. The ecology of Lutzomyia umbratilis (Diptera, Psychodidae), the major vector to man of Leishmania braziliensis guyanensis in northeastern Amazonian Brazil. Bull Ent Res 76 :21–40.
- 37↑
Pardo RH, Cabrera OL, Becerra J, Fuya P, Ferro C, 2006. Lutzomyia longiflocosa as suspected vector of cutaneous leishmaniasis in a focus of cutaneous leishmaniasis on the sub-andean region of Tolima department, Colombia, and the knowledge on sandflies by the inhabitants. Biomedica (Bogota) 26 (Suppl 1):95–108.
- 38↑
Saravia NG, Holguin AF, McMahon-Pratt D, D’Alessandro A, 1985. Mucocutaneous leishmaniasis in Colombia: Leishmania braziliensis subspecies diversity. Am J Trop Med Hyg 34 :714–720.
- 39↑
McMahon-Pratt D, David J, 1981. Monoclonal antibodies that distinguish between New World species of Leishmania. Nature 291 :581–593.
- 40
McMahon-Pratt D, Bennett E, David JR, 1982. Monoclonal antibodies that distinguish subspecies of Leishmania braziliensis. J Immunol 129 :926–927.
- 41↑
Organización Mundial de la Salud, 1993. Uso de anticuerpos monoclonales en la identificación de Leishmania de importancia médica en Latinoamérica. Manual de Procedimientos, Programa Especial para Investigación y Entrenamiento en Enfermedades Tropicales. Ginebra, Colombia: Organización Mundial de la Salud, 1–20.
- 42↑
Lanham SM, Grendon JM, Miles MA, Povoa MM, Almeida de Souza AA, 1981. A comparison of electrophoretic methods for isoenzyme characterization of trypanosomatids. I: Standard stocks of Trypanosoma cruzi zymodemes from northeast Brazil. Trans R Soc Trop Med Hyg 75 :742–750.
- 43↑
Cupolillo E, Grimaldi G Jr, Momen H, 1994. A general classification of New World Leishmania using numerical zymotaxonomy. Am J Trop Med Hyg 50 :296–311.
- 44↑
Saravia NG, Segura I, Holguin AF, Santrich C, Valderrama L, Ocampo C, 1998. Epidemiologic, genetic, and clinical associations among phenotypically distinct populations of Leishmania (Viannia ) in Colombia. Am J Trop Med Hyg 59 :86–94.
- 45↑
Romero GA, Guerra MV, Paes MG, Macêdo VO, 2001. Comparison of cutaneous leishmaniasis due to Leishmania (Viannia) braziliensis and L. (V.) guyanensis in Brazil: therapeutic response to meglumine antimoniate. Am J Trop Med Hyg 65 :456–465.
- 46↑
Garcia AL, Tellez T, Parrado R, Rojas E, Bermudez H, Dujardin JC, 2007. Epidemiological monitoring of American tegumentary leishmaniasis: molecular characterization of a peridomestic transmission cycle in the Amazonian lowlands of Bolivia. Trans R Soc Trop Med Hyg 101 :1208–1213.
- 47↑
Marco JD, Barroso PA, Calvopina M, Kumazawa H, Furuya M, Korenaga M, Cajal SP, Mora MC, Rea MM, Borda CE, Basombrio MA, Taranto NJ, Hashiguchi Y, 2005. Species assignation of Leishmania from human and canine American tegumentary leishmaniasis cases by multilocus enzyme electrophoresis in North Argentina. Am J Trop Med Hyg 72 :606–611.
- 48↑
Balbino VQ, Marcondes CB, Alexander B, Luna LK, Lucena MM, Mendes AC, Andrade PP, 2001. First report of Lutzomyia (Nyssomyia) umbratilis Ward & Frahia, 1977 outside of Amazonian Region, in Recife, State of Pernambuco, Brazil (Diptera: Psychodidae: Phlebotominae). Mem Inst Oswaldo Cruz 96 :315–317.
- 49↑
Young D, Duncan M, 1994. Guide to the identification and geographic distribution of Lutzomyia sand flies in Mexico, the West Indies, Central and South America (Diptera: Psychodidae). Mem Entomol Inst 54 :1–881.
- 50↑
Cardenas R, Pabón E, Anaya H, Sandoval C, 2005. Presencia de Lutzomyia longiflocosa (Diptera: Psychodidae) en el foco de leishmaniasis tegumentaria americana del municipio de Abrego, Norte de Santander. Primer registro para el departamento. Rev Inst Facultad Salud Universidad de Pamplona 3 :7–14.
- 51↑
Cardenas R, Romo G, Santamaria E, Ferro C, 1999. Lutzomyia longiflocosa (Diptera:Psychodidae) posible vector en el foco de leishmaniasis cutánea del municipio de Planadas, zona cafetera del Tolima. Biomedica (Bogota) 19 :239–244.
- 52↑
Santamaria E, Castillo M, Cardenas E, Bello F, Ayala M, Ferro C, 1998. Transmisión experimental de Leishmania braziliensis a hamster por picadura de Lutzomyia longiflocosa (Dipetera: Psychodidae) provenientes de un foco endémico en la zona cafetera colombiana. Médicas UIS 12 :279–284.
- 53↑
Arevalo J, Ramirez L, Adaui V, Zimic M, Tulliano G, Miranda-Verastegui C, Lazo M, Loayza-Muro R, de Doncker S, Maurer A, Chappuis F, Dujardin JC, Llanos-Cuentas A, 2007. Influence of Leishmania (Viannia) species on the response to antimonial treatment in patients with American tegumentary leishmaniasis. J Infect Dis 195 :1846–1851.
- 54
Soto J, Arana BA, Toledo J, Rizzo N, Vega JC, Diaz A, Luz M, Gutierrez P, Arboleda M, Berman JD, Junge K, Engel J, Sindermann H, 2004. Miltefosine for new world cutaneous leishmaniasis. Clin Infect Dis 38 :1266–1272.
- 55↑
Navin TR, Arana BA, Arana FE, Berman JD, Chajón JF, 1992. Placebo-controlled clinical trial of sodium stibogluconate (Pentostam) versus ketoconazole for treating cutaneous leishmaniasis in Guatemala. J Infect Dis 165 :528–534.
- 56↑
Tojal da Silva AC, Cupolillo E, Volpini AC, Almeida R, Sierra Romero GA, 2006. Species diversity causing human cutaneous leishmaniasis in Rio Branco, state of Acre, Brazil. Trop Med Int Health 11 :1388–1398.
- 57
Lucas CM, Franke ED, Cachay MI, Tejada A, Cruz ME, Kreutzer RD, Barker DC, McCann SH, Watts DM, 1998. Geographic distribution and clinical description of leishmaniasis cases in Peru. Am J Trop Med Hyg 59 :312–317.
- 58
Calvopina M, Armijos RX, Hashiguchi Y, 2004. Epidemiology of leishmaniasis in Ecuador: current status of knowledge–a review. Mem Inst Oswaldo Cruz 99 :663–672.
- 59
Calvopina M, Armijos RX, Marco JD, Uezato H, Kato H, Gomez EA, Korenaga M, Barroso PA, Mimori T, Cooper PJ, Nonaka S, Hashiguchi Y, 2006. Leishmania isoenzyme polymorphisms in Ecuador: relationships with geographic distribution and clinical presentation. BMC Infect Dis 6 :139.
- 60
Rotureau B, 2006. Ecology of the Leishmania species in the Guianan ecoregion complex. Am J Trop Med Hyg 74 :81–96.
- 61
Rotureau B, Ravel C, Nacher M, Couppie P, Curtet I, Dedet JP, Carme B, 2006. Molecular epidemiology of Leishmania (Viannia) guyanensis in French Guiana. J Clin Microbiol 44 :468–473.
- 62
Bonfante-Garrido R, Melendez E, Barroeta S, de Alejos MA, Momen H, Cupolillo E, McMahon-Pratt D, Grimaldi G Jr, 1992. Cutaneous leishmaniasis in western Venezuela caused by infection with Leishmania venezuelensis and L. braziliensis variants. Trans R Soc Trop Med Hyg 86 :141–148.
- 63
Desjeux P, Dedet JP, 1989. Isoenzyme characterization of 112 Leishmania isolates from French Guiana. Trans R Soc Trop Med Hyg 83 :610–612.
- 64↑
Grimaldi G Jr, David JR, McMahon-Pratt D, 1987. Identification and distribution of New World Leishmania species characterized by serodeme analysis using monoclonal antibodies. Am J Trop Med Hyg 36 :270–287.