Hemoculture and Polymerase Chain Reaction Using Primers TCZ1/TCZ2 for the Diagnosis of Canine and Feline Trypanosomiasis

Abstract

Introduction. American trypanosomiasis, also known as Chagas disease, is a zoonosis caused by Trypanosoma cruzi (T. cruzi). Dogs and cats participate actively in this parasite's transmission cycle. This study aimed at evaluating the occurrence of T. cruzi in dogs and cats from Botucatu, SP, Brazil, as well as at evaluating the technique of hemoculture in LIT (liver infusion tryptose) medium by polymerase chain reaction (PCR). Methods. Blood samples were collected from 50 dogs and 50 cats in Botucatu-SP, Brazil. For hemoculture, the samples were inoculated in LIT medium, and readings were performed for four months. Upon completion of such period, all the hemocultures were processed for parasitic DNA extraction. The PCR reactions were performed by using primers TCZ1/TCZ2. Results. Ten dogs and ten cats (20%) were positive to PCR, and four dogs and three cats (7%) were positive to hemoculture. Only in a one cat sample (1%) there was confirmation of positive hemoculture by PCR for T. cruzi. Conclusions. Results showed that PCR was a suitable tool for the confirmation of the parasite detection in hemoculture samples, and that dogs and cats from Botucatu, SP, Brazil, are maintaining the role of household reservoirs of T. cruzi, which reinforces the need for constant epidemiologic surveillance for this zoonosis.

Dogs, cats, parasites, and humans in Brazil: opening the black box

“…Dogs have been found infected by vector-borne protozoa, including Babesia gibsoni , Babesia vogeli , Rangelia vitalii , Hepatozoon canis , Leishmania amazonensis , Leishmania braziliensis , Leishmania infantum , Trypanosoma cruzi , and Trypanosoma evansi [ 73 , 78 - 82 , 85 , 87 - 90 , 96 , 102 - 104 , 109 - 113 , 117 - 121 ],[ 124 , 128 - 130 ]. Other protozoa of unknown pathogenicity (e.g., Trypanosoma caninum ) have also been described in Brazilian dogs [ 108 ].…”

“…Serological tests are widely used to assess exposure to pathogens, such as B. vogeli , Leishmania spp., N. caninum , and T. gondii [ 168 , 169 , 184 , 196 - 198 ]. The use of molecular tools for diagnosing protozoan parasites (e.g., B. vogeli , H. canis , and L. infantum ) is becoming more and more popular, but it is still mostly restricted to research [ 121 , 199 - 204 ]. Indeed, current PCR protocols have shown a good level of concordance with parasitological methods [ 150 ].…”

Reservoir host competence and the role of domestic and commensal hosts in the transmission of Trypanosoma cruzi

“…The probability of bug infection after feeding on an infected host is crucially related to bloodmeal size, which varies among bug stages, duration of exposure to the host and other factors (reviewed in Gürtler et al, 1996a). For example, the pioneering xenodiagnostic surveys of dogs conducted in Brazil (Freitas, 1950;Freitas et al, 1952;Martins et al, 1945) and recent ones using hemoculture (5-8 mL of host blood) and/or PCR (Bezerra et al, 2014;Eloy and Lucheis, 2012;Lucheis et al, 2005) documented the frequent occurrence of parasitologically-positive dogs or cats (Table 1). In contrast, dogs seropositive for T. cruzi across several areas were hemoculture-negative when smaller amounts (0.2-0.4 mL) of blood were tested (Roque et al, 2008;Xavier et al, 2012;Rocha et al, 2013).…”

Tripanosomiasis americana en un canino del nordeste argentino: reporte del caso clínico

“…De acuerdo a los mamíferos intervinientes puede definirse un ciclo doméstico-peridoméstico, cuando intervienen el hombre y animales como el perro y el gato, o un ciclo selvático cuando se involucran marsupiales, edentados, quirópteros, carnívoros y roedores silvestres 15 . Se ha considerado que el perro juega un papel muy importante en la transmisión de T. cruzi domiciliar, constituyendo un nexo entre los ambientes domésticos, peridomésticos y selváticos, dado sus hábitos de caza para alimentarse, su estricta convivencia con el hombre y la alta capacidad infectante del vector 10 .…”

“…En latinoamérica el perro juega un papel muy importante en la transmisión de T. cruzi domiciliar, pues constituye un reservorio altamente infectante para el vector 10 . Asímismo, el índice de infección del vector con el parásito aumenta con respecto al número de perros infectados.…”