Human infectiousness and parasite load in chronic patients seropositive for Trypanosoma cruzi in a rural area of the Argentine Chaco.

摘要: Abstract A key parameter in the transmission of vector-borne infections, including Chagas disease, is ability different host species to transmit parasite vector (infectiousness). Here, we determined infectiousness Trypanosoma cruzi-seropositive humans examined by artificial xenodiagnosis (XD), established its relationship with T. cruzi DNA levels (a surrogate intensity parasitemia) quantified real-time PCR (qPCR), and assessed whether was associated body mass index (BMI), age, ethnic background genotype. XD performed 117 T. residents from Pampa del Indio load 81 them. Using optical microscopy (OM) 33.6% seropositive people tested were infectious this fraction nearly doubled (66.0%) when triatomines kDNA-PCR. The mean (defined as percentage all infected detected OM at any time point among total number insects 30 days post-feeding) 5.2%, 0.51 equivalents per ml. Infectiousness negatively age BMI, positively detection parasitemia kDNA-PCR, qPCR bivariate analysis. Patients a positive exhibited significantly higher load. multiple regression, (positively) household presence infestans Qom group (negatively); no significant association observed or interaction ethnicity. We did not find associations between identified DTUs aggregated: 18% generated 80% triatomines. Detecting treating super-infectious human would disproportionally impact on domestic risks. Nonetheless, treatment eligible who meet inclusion criteria regardless their should be ensured improve prognosis.