Background Triatoma dimidiata, currently the major Central American vector of Trypanosoma cruzi, the parasite that causes Chagas disease, inhabits caves throughout the region. This research investigates the possibility that cave dwelling T. dimidiata might transmit the parasite to humans and links the blood meal sources of cave vectors to cultural practices that differ among locations. Methodology/Principal Findings We determined the blood meal sources of twenty-four T. dimidiata collected from two locations in Guatemala and one in Belize where human interactions with the caves differ. Blood meal sources were determined by cloning and sequencing PCR products amplified from DNA extracted from the vector abdomen using primers specific for the vertebrate 12S mitochondrial gene. The blood meal sources were inferred by ≥99% identity with published sequences. We found 70% of cave-collected T. dimidiata positive for human DNA. The vectors had fed on 10 additional vertebrates with a variety of relationships to humans, including companion animal (dog), food animals (pig, sheep/goat), wild animals (duck, two bat, two opossum species) and commensal animals (mouse, rat). Vectors from all locations fed on humans and commensal animals. The blood meal sources differ among locations, as well as the likelihood of feeding on dog and food animals. Vectors from one location were tested for T. cruzi infection, and 30% (3/10) tested positive, including two positive for human blood meals. Conclusions/Significance Cave dwelling Chagas disease vectors feed on humans and commensal animals as well as dog, food animals and wild animals. Blood meal sources were related to human uses of the caves. We caution that just as T. dimidiata in caves may pose an epidemiological risk, there may be other situations where risk is thought to be minimal, but is not.
Monroy C, Castro X, Bustamante DM, Pineda S, Rodas A, et al., editors (2011) An ecosystem approach for the prevention of Chagas disease in Rural Guatemala. New York, NY, USA/International develomment Research Centre, Ottawa, Canada: Springer.
Bustamante DM, Monroy C, Menes M, Rodas A, Salazar-Schettino PM, et al. (2004) Metric variation among geographic populations of the Chagas vector Triatoma dimidiata (Hemiptera: Reduviidae: Triatominae) and related species. J Med Entomol 41: 296–301. doi: 10.1603/0022-2585-41.3.296
Calderon CI, Dorn PL, Melgar S, Chavez JJ, Rodas A, et al. (2004) A preliminary assessment of genetic differentiation of Triatoma dimidiata (Hemiptera: Reduviidae) in Guatemala by random amplification of polymorphic DNA-polymerase chain reaction. J Med Entomol 41: 882–887. doi: 10.1603/0022-2585-41.5.882
Catala S, Sachetto C, Moreno M, Rosales R, Salazar-Schetrino PM, et al. (2005) Antennal phenotype of Triatoma dimidiata populations and its relationship with species of phyllosoma and protracta complexes. Journal of medical entomology 42: 719–725. doi: 10.1603/0022-2585(2005)042[0719:apotdp]2.0.co;2
Dorn PL, Calderon C, Melgar S, Moguel B, Solorzano E, et al. (2009) Two distinct Triatoma dimidiata (Latreille, 1811) taxa are found in sympatry in Guatemala and Mexico. PLoS Negl Trop Dis 3: e393. doi: 10.1371/journal.pntd.0000393
Pizarro JC, Stevens L (2008) A new method for forensic DNA analysis of the blood meal in Chagas disease vectors demonstrated using Triatoma infestans from Chuquisaca, Bolivia. PLoS ONE 3: e3585. doi: 10.1371/journal.pone.0003585
Pizarro JC, Lucero DE, Stevens L (2007) PCR reveals significantly higher rates of Trypanosoma cruzi infection than microscopy in the Chagas vector, Triatoma infestans: High rates found in Chuquisaca, Bolivia. Bmc Infectious Diseases 7: 66. doi: 10.1186/1471-2334-7-66
Stevens L, Dorn P, Hobson J, de la Rua N, Lucero D, et al. (2012) Evidence of human and other vertebrate bloodmeals and Trypanosoma cruzi infection in Chagas disease vectors from the United States. Emerging Infectious Diseases 18: 646–649. doi: 10.3201/eid1804.111396
Buitrago NL, Bosseno MF, Waleckx E, Bremond P, Vidaurre P, et al. (2013) Risk of transmission of Trypanosoma cruzi by wild Triatoma infestans (Hemiptera: Reduviidae) in Bolivia supported by the detection of human blood meals. Infect Genet Evol 19C: 141–144. doi: 10.1016/j.meegid.2013.07.002
Kjos SA, Marcet PL, Yabsley MJ, Kitron U, Snowden KF, et al. (2013) Identification of Bloodmeal Sources and Trypanosoma cruzi Infection in Triatomine Bugs (Hemiptera: Reduviidae) from Residential Settings in Texas, the United States. Journal of Medical Entomology 50: 1126–1139. doi: 10.1603/me12242
Brown LA (2010) Communal and Personal Hunting Shrines Around Lake Atitlan, Guatemala. In: Golden C, Houston S, Skidmore J, editors. Maya Archaeology. San Francisco: Precolumbia Mesoweb Press. pp. 36–59.
Roque AL, Xavier SC, Gerhardt M, Silva MF, Lima VS, et al. (2013) Trypanosoma cruzi among wild and domestic mammals in different areas of the Abaetetuba municipality (Para State, Brazil), an endemic Chagas disease transmission area. Vet Parasitol 193: 71–77. doi: 10.1016/j.vetpar.2012.11.028
Gottdenker NL, Calzada JE, Saldana A, Carroll CR (2011) Association of anthropogenic land use change and increased abundance of the Chagas disease vector Rhodnius pallescens in a rural landscape of Panama. Am J Trop Med Hyg 84: 70–77. doi: 10.4269/ajtmh.2011.10-0041
Garcia M, Menes M, Dorn PL, Monroy C, Richards B, et al. (2013) Reproductive isolation revealed in preliminary crossbreeding experiments using field collected Triatoma dimidiata (Hemiptera: Reduviidae) from three ITS-2 defined groups. Acta Trop 128: 714–718. doi: 10.1016/j.actatropica.2013.09.003
Torres-Montero J, Lopez-Monteon A, Dumonteil E, Ramos-Ligonio A (2012) House infestation dynamics and feeding sources of Triatoma dimidiata in central Veracruz, Mexico. Am J Trop Med Hyg 86: 677–682. doi: 10.4269/ajtmh.2012.11-0746