Temporal differences in blood meal detection from the midguts of Triatoma infestans

Abstract

SUMMARYWe used genus/species specific PCRs to determine the temporal persistence of host DNA in Triatoma infestans experimentally fed on blood from six common vertebrate species: humans, domestic dogs, guinea pigs, chickens, mice, and pigs. Twenty third or fourth instar nymphs per animal group were allowed to feed to engorgement, followed by fasting-maintenance in the insectary. At 7, 14, 21, or 28 days post-feeding, the midgut contents from five triatomines per group were tested with the respective PCR assay. DNA from all vertebrate species was detected in at least four of five study nymphs at seven and 14 days post-feeding. DNA of humans, domestic dogs, guinea pigs, pigs, and chickens were more successfully detected (80-100%) through day 21, and less successfully (20-100%) at day 28. Findings demonstrate that species-specific PCRs can consistently identify feeding sources of T. infestans within two weeks, a biologically relevant time interval.

Ecological, Social and Biological Risk Factors for Continued Trypanosoma cruzi Transmission by Triatoma dimidiata in Guatemala

“…Although synanthropic rodents were previously found to be infected with T. cruzi [52], [53], their role in domestic transmission has not been fully documented. The molecular detection of a blood meal indicates blood meals taken within the last 2–3 weeks [53].…”

“…The molecular detection of a blood meal indicates blood meals taken within the last 2–3 weeks [53]. The detection of multiple blood meals in nymphs, including human blood meals in outdoor structures, suggests that immature stages actively move in search of blood meals, as found in another Municipality [51] and for T. infestans in Peru and Argentina [4], [6].…”

Domestic Animal Hosts Strongly Influence Human-Feeding Rates of the Chagas Disease Vector Triatoma infestans in Argentina

“…This is likely related to degradation of host DNA during the blood meal's long periods of storage in the anterior midgut. Unlike serologic methods for bloodmeal identification [49], genus- or species-specific PCRs used to detect the persistence of host DNA in T. infestans experimentally fed on major domestic host species identified host sources consistently only up to two weeks post-feeding, and to a much lesser extent up to four weeks post-feeding [62]. For domestic bug populations exposed to a limited, well-known range of domestic host species, the ELISA test is a cost-effective option showing high sensitivity and specificity combined with high-throughput processing.…”

Hemi-Nested PCR and RFLP Methodologies for Identifying Blood Meals of the Chagas Disease Vector, Triatoma infestans

“…For Chagas disease vectors, several methodologies have been described using species-specific oligonucleotides to determine feeding preferences [3], [4], [8], [19]. The disadvantage of such techniques is the need for a priori knowledge of potential hosts in the area.…”

“…The MC of laboratory-fed triatomines were obtained via dissection and stored at −20°C in Tris-EDTA (TE) buffer (10 mM Tris-HCl pH 8.0, 1 mM EDTA) at a 1∶10 ratio. A 100 µL aliquot of this MC was used in DNA extraction methods previously described and stored at −20°C until used in the PCR analysis [19].…”