ABSTRACT:
Visceral leishmaniasis (VL) is caused by the protozoon Leishmania infantum . Transmission of this parasite to hosts occurs mainly through the bite of infected sand flies. However, alternative infection routes have been hypothesized, especially in areas where the biological vector is absent. The exact time of infection and whether in utero transmission occurs have still not been fully elucidated. This report demonstrates molecular evidence of vertical transmission ofL. infantum from a pregnant dog to the embryo. Samples (e.g. vulva, vagina, cervix, uterine body, uterine horn and ovaries) from a female naturally infected byL. infantum and from her embryo were molecularly analyzed by means of qPCR and cPCR followed by DNA sequencing. The gestational age was estimated to be 23±1 day. Through qPCR, the presence ofL. infantum DNA was detected in all the samples analyzed (n=7), including the embryo, conversely through cPCR, only four samples (vagina, cervix, uterine body and embryo) were positive. This study demonstrated that transmission ofL. infantum from a pregnant dog to the embryo might occur in the early days of pregnancy. In conclusion, this is the first report showingL. infantum infecting a canine embryo.
Key words:
leishmaniasis; dog; vertical infection; embryo