Biological Parameters of Two Triatoma protracta Subspecies (Hemiptera: Reduviidae)

In recent years, concerns about Chagas disease in the United States have increased.Triatomine bug (Hemiptera: Reduviidae) populations are the vectors of the parasite Trypanosoma cruzi Chagas (Trypanosomatida: Trypanosomatidae), which causes Chagas disease, although the route of transmission is considered inefficient in United States. However, more studies on triatomine feeding and defecation behavior are needed. In this study, six related biological parameters from two populations of Triatoma protracta protracta (Uhler) and T. p. woodi (Uhler) from Mexican locations near the U.S. border were evaluated.The four population life cycles were less than 6 mo (161-171 d), with 9-10 blood meals needed to molt. Mortality rates were similar (31-38%) among the four populations. Triatoma p. woodi from Hidalgo, Coahuila was the most aggressive one. Feeding times were over 10 min, increasing with instar in all populations. Defecation behaviors varied among populations. High percentages of male and female fourth- and fifth-instar nymphs of T. p. protracta from Imuris and both populations of T. p. woodi defecated immediately after or <1 min of feeding. Lower percentages were observed for T. p. protracta from Jacume. Because most parameters were similar among the four populations, independent of their subspecies and their geographic origin, we considered that T. p. protracta and T. p. woodi are efficient vectors of T. cruzi. In contrast, defecation patterns were noticeably different among some of the four triatomine populations studied. Our results highlight the importance of studying the biological parameters of local triatomine populations.They also contribute to increasing the knowledge of North American triatomine behavior and defecation patterns. [GRAPHICS] .

Automated summary

In recent years, concerns about Chagas disease in the United States have increased due to the increasing presence of Triatomine bugs. This study evaluated biological parameters of two populations of Triatoma protracta protracta and T. p. woodi from Mexican locations near the U.S. border, finding similar mortality rates and feeding behaviors among the populations, but differences in defecation patterns. The study suggests that Triatoma protracta and Triatoma woodi are efficient vectors of Trypanosoma cruzi, contributing to the understanding of North American Triatomine behavior and defecation patterns.