An Iron-Superoxide Dismutase Antigen-Based Serological Screening of Dogs Indicates Their Potential Role in the Transmission of Cutaneous Leishmaniasis and Trypanosomiasis in Yucatan, Mexico

Abstract

An increasing number of studies have reported high infection rates for American cutaneous leishmaniasis in dogs, which have thus been proposed as the reservoir host. Canine leishmaniasis is widespread in different states in Mexico, where a number of Leishmania species have been isolated from dogs. In the present study, the detection of different Leishmania species is described in stray dogs from two localities, namely Tulum and Celestún on the Yucatan Peninsula (Mexico). The use of iron-superoxide dismutase excreted by the parasites as the antigen fraction and enzyme-linked immunosorbent assay and western blot tests allowed us to confirm the presence of at least three species of Leishmania (Le. mexicana, Le. braziliensis, and Le. panamensis), some of which are reported for the first time in this species. In addition to a high prevalence of Le. mexicana and Le. braziliensis, and to a lesser degree, Le. panamensis, there is a significant prevalence of Trypanosoma cruzi, suggesting that the dog may be a source of transmission of trypanosomiasis. However, a more thorough epidemiological study on the dog population, both wild as well as urban, of the Yucatan Peninsula will be required to design a control strategy for these diseases, paying particular attention to the population affected and even broadening the study to other Mexican states as well as neighboring countries. These results again confirm that iron-superoxide dismutase excreted by the different trypanosomatid species constitutes a good source of antigen for serodiagnosis in epidemiological studies.

Anticuerpos de Trypanosoma cruzi, Leishmania mexicana y Leishmania braziliensis en perros domiciliados de Tabasco, México

“…Todas las muestras se analizaron por triplicado en placas de microtitulación. La mediana y desviación estándar (SD) de la densidad óptica de los sueros de control negativo (pertenecientes a la Facultad de Ciencias de la Universidad de Granada, España) se utilizaron para calcular el valor de corte (mediana +3×SD) de acuerdo con la técnica sugerida por Longoni (8).…”

“…Monitoring of diseases such as Trypanosomiasis and Leishmaniasis in pets, is of great importance (16), as animals like dogs, act as reservoirs of the parasite in endemic areas, and it is necessary to identify the movement of agents in order to prevent possible infection in humans (4 incrementos en la presentación de la enfermedad en los propietarios de las mascotas infectadas (8,17). La mayor convivencia de los animales domésticos con la población humana, demuestra una conexión entre el medio urbano -rural y peridoméstico, trayendo consigo diversas repercusiones en salud pública (22 …”

“…Protein content was determined using the Bio-Rad assay, according to the Bradford method (Inmunochemicals Sigma, St. Louis), using bovine serum albumin as standard as described by Marin (12). The Fe-SOD obtained was used as antigen in the ELISA and Western Blot for the diagnosis of T. cruzi, L. mexicana and L. braziliensis (8).…”

“…All samples were tested in triplicate in microtiter plates. The median and standard deviation (SD) of optical density of the negative control sera (belonging to the faculty of the University of Granada, Spain) were used to calculate the cutoff value (mean +3xSD) according to the technique suggested by ongoni (8).…”

“…The prevalence in the Yucatan Peninsula reported for L. braziliensis (7.52%), L. infantum (6.07%) and L. mexicana (20.63%) (7), while it was reported 41.4% for the peninsula in general (8) and 30.2% (9) for Merida. The most common worldwide used techniques for detection of these agents are diagnostic techniques Enzymelinked Immunosorbent Assay (ELISA), indirect immunofluorescence (IFI) and Polymerase Chain Reaction (PCR).…”