Lesões genitais em cadelas naturalmente infectadas com leishmania chagasi e soroconversão de cadelas acasaladas com cães portadores.

Abstract

Visceral leishmaniasis is primarily transmitted by a biological invertebrate vector, although transmission in the absence of the vector has been reported, including venereal transmission in humans. Considering the importance of alternative routes of transmission for disease control, the goals of this study were (i) to characterize genital lesions and to detect Leishmania sp. in bitches with visceral leishmaniasis, and (ii) to verify the occurrence of seroconversion and presence of amastigotes in organs and tissues of bitches free of Leishmania sp. that have copulated with male dogs shedding Leishmania sp. in the semen. Ten adult bitches seropositive for leishmaniasis were selected and divided into two groups: (i) symptomatic bitches (n=5) and (ii) asymptomatic bitches (n=5). Five adult serologically negative bitches were used as controls. Samples were collected from both ovaries, uterine tubes, uterine horns, uterine body, cervix, vagina, vulva, spleen and liver, histologically evaluated, and processed for imunodetection of Leishmania sp. Samples of the same tissues were processed for detection Leishmania kDNA by PCR. Leishmania amastigotes were observed only in the vulva and vagina of the bitches with visceral leishmaniasis, although infected and control bitches had similar intensity and distribution of inflammation. Although Leishmania kDNA was detected by PCR in the internal genital organs, no evidences of amastigotes or lesions associated with visceral leishmaniasis were observed in these segments. Thirteen male dogs with visceral leishmaniasis were selected and tested for shedding of Leishmania sp. in the semen. Ten adults bitches free of Leishmania, maintained in an environment free of phlebotomines, copulated with serologically positive male dogs that eliminated Leishmania sp. in the semen. After copulations, bitches were serologically evaluated every 15 days. At the end of the period of observation (five months after the last mating), samples of all the genital organs, spleen, liver, and lymph nodes were collected, histologically evaluated, and processed for imunodetection of Leishmania sp. Eleven of the dogs with visceral leishmaniasis that were tested shed Leishmania sp. in the semen, and shedding was intermittent and randomly distributed over the time-course. Two of the ten bitches had seroconversion. However, no amastigotes were observed in tissues.