REFERENCES

01. WHO - World Health Organization. Chagas disease in Latin America: an epidemiological update based on 2010 estimates. Wkly Epidemiol Rec. 2015; 90(6): 33-44.

02. Lent H, Wygodzinsky P. Revision of the Triatominae (Hemiptera, Reduviidae), and their significance as vectors of Chagas’ disease. Bull Am Mus Nat Hist. 1979; 163: 123-520.

03. Costa J, Dale C, Galvão C, Almeida CE, Dujardin JP. Do the new triatomine species pose new challenges or strategies for monitoring Chagas disease? An overview from 1979-2021. Mem Inst Oswaldo Cruz. 2021; 116: e210015. https://doi.org/10.1590/0074- 02760210015.

04. Galvão C. Triatomine bugs: history, control, and citizen surveillance. Dis Biol Genet Socioecol. 2025; 1(3): 8. https://doi. org/10.53941/dbgs.2025.100008.

05. Gürtler RE, Kitron U, Cecere MC, Segura EL, Cohen JE. Sustainable vector control and management of the Chagas disease in the Gran Chaco, Argentina. Proc Natl Acad Sci USA. 2007; 104(41): 16194-9. https://doi.org/10.1073/pnas.0700746104.

06. Zeledon R. Triatoma infestans and its importance in the Americas. Washington, D.C.: Pan American Health Organization; 1981. (Scientific Publication No. 416). Available from: https://iris.paho.org.

07. Schofield CJ. Triatominae: biology and control. Bognor Regis: Eurocommunica Publications; 1994.

08. Dujardin JP, Schofield CJ, Panzera F. Les vecteurs de la maladie de Chagas. Brussels: Académie Royale des Sciences d’Outre- Mer; 2000.

09. Gürtler RE, Gaspe MS, Macchiaverna NP, Enriquez GF, Rodríguez- Planes LI, Fernández MP, et al. The pampa del indio project: district-wide quasi-elimination of Triatoma infestans after a 9-year intervention program in the Argentine Chaco. PLoS Negl Trop Dis. 2023; 17(4): e0011252. https://doi.org/10.1371/journal.pntd.0011252.

10. Gaspe MS, Gurevitz JM, Gürtler RE, Dujardin JP. Origins of house reinfestation with Triatoma infestans after insecticide spraying in the Argentine Chaco using wing geometric morphometry. Infect Genet Evol. 2013; 17: 93-100. https://doi.org/10.1016/j. meegid.2013.03.045.

11. Marcet PL, Mora MS, Cutrera AP, Jones L, Gürtler RE, Kitron U, et al. Genetic structure of Triatoma infestans populations in rural communities of Santiago del Estero, northern Argentina. Infect Genet Evol. 2008; 8(6): 835-46. https://doi.org/10.1016/j. meegid.2008.08.002.

12. Schofield CJ, Matthews JN. Theoretical approach to active dispersal and colonization of houses by Triatoma infestans. J Trop Med Hyg. 1985; 88(3): 211-22.

13. Bezerra CM, Barbosa SE, Souza RCM, Diotaiuti L, Pires HHR, Pavan MG, et al. Microsatellite variation reveals population structure in Triatoma brasiliensis (Hemiptera: Reduviidae). BMC Genet. 2020; 21(1): 92. https://doi.org/10.1186/s12863-020-00897-y.

14. Manrique G, Lazzari CR. Sexual behaviour and stridulation during mating in Triatoma infestans (Hemiptera: Reduviidae). Mem Inst Oswaldo Cruz. 1994; 89(4): 629-33. https://doi.org/10.1590/ S0074-02761994000400021.

15. Lobbia PA, Rodríguez C, Remón C, Manteca-Acosta M. Reproductive consequences of the interaction Trypanosoma cruzi — Triatoma infestans and its trade-off with survival. J Invertebr Pathol. 2024; 206: 108-83. https://doi.org/10.1016/j.jip.2024.108183.

16. García BA, Zheng L, Pérez de Rosas AR, Segura EL. Isolation and characterization of polymorphic microsatellite loci in the Chagas’ disease vector Triatoma infestans (Hemiptera: Reduviidae). Mol Ecol Notes. 2004; 4(4): 568-71. https://doi.org/10.1111/j.1471- 8286.2004.00730.x.

17. Marcet PL, Lehmann T, Groner G, Gürtler RE, Kitron U, Dotson EM. Identification and characterization of polymorphic microsatellite markers in the Chagas disease vector Triatoma infestans (Heteroptera: Reduviidae). Infect Genet Evol. 2006; 6(1): 32-7. https://doi.org/10.1016/j.meegid.2005.08.006.

18. Oosterhout CV, Hutchinson W, Wills D, Shipley P. MICROCHECKER: software for identifying and correcting genotyping errors in microsatellite data. Mol Ecol Notes. 2004; 4: 535-8. https://doi.org/10.1111/j.1471-8286.2004.00684.x.

19. Peakall R, Smouse PE. genealex 6: genetic analysis in Excel. Population genetic software for teaching and research. Mol Ecol Notes. 2006; 6: 288-95. https://doi.org/10.1111/j.1471-8286.2005.01155.x.

20. Rousset F. genepop’007: a complete re-implementation of the genepop software for Windows and Linux. Mol Ecol Resour. 2008; 8(1): 103-6. https://doi.org/10.1111/j.1755-0998.2007.01960.x.

21. Weir BS, Cockerham CC. Estimating F-statistics for the analysis of population structure. Evolution. 1984; 38(6): 1358-70. https:// doi.org/10.1111/j.1558-5646.1984.tb05657.x.

22. Jones OR, Wang J. COLONY: a program for parentage and sibship inference from multilocus genotype data. Mol Ecol Resour. 2010; 10(3): 551-5. https://doi.org/10.1111/j.1755-0998.2009.02756.x.

23. Wang J, Santure AW. Parentage and sibship inference from multilocus genotype data under polygamy. Genetics. 2009; 181(4): 1579-94. https://doi.org/10.1534/genetics.108.100214.

24. Cornuet JM, Luikart G. Description and power analysis of two tests for detecting recent population bottlenecks from allele frequency data. Genetics. 1996; 144(4): 2001-14. https://doi. org/10.1093/genetics/144.4.2001.

25. Luikart G, Allendorf FW, Cornuet JM, Sherwin WB. Distortion of allele frequency distributions provides a test for recent population bottlenecks. J Hered. 1998; 89(3): 238-47. https://doi. org/10.1093/jhered/89.3.238.

26. Yan JL, Dobbin ML, Dukas R. Sexual conflict and sexual networks in bed bugs: the fitness cost of traumatic insemination, female avoidance and male mate choice. Proc Biol Sci. 2024; 291(2027): 2023-2808. https://doi.org/10.1098/rspb.2023.2808.

27. Pizarro JC, Gilligan LM, Stevens L. Microsatellites reveal a high population structure in Triatoma infestans from Chuquisaca, Bolivia. PLoS Negl Trop Dis. 2008; 2(3): e202. https://doi. org/10.1371/journal.pntd.0000202.

28. Brenière SF, Bosseno MF, Vargas F, Yaksic N, Noireau F, Noel S, et al. Smallness of the panmictic unit of Triatoma infestans (Hemiptera: Reduviidae). J Med Entomol. 1998; 35(6): 911-7. https:// doi.org/10.1093/jmedent/35.6.911.

29. Brenière SF, Bosseno MF, Vargas F, Yaksic N, Noireau F, Noel S, et al. Smallness of the panmictic unit of Triatoma infestans (Hemiptera: Reduviidae). J Med Entomol. 1998; 35(6): 911-7. https:// doi.org/10.1093/jmedent/35.6.911.

30. Pérez de Rosas AR, Segura EL, Fichera L, García BA. Macrogeographic and microgeographic genetic structure of the Chagas’ disease vector Triatoma infestans (Hemiptera: Reduviidae) from Catamarca, Argentina. Genetica. 2008; 133(3): 247-60. https://doi. org/10.1007/s10709-007-9205-0.

31. Lardeux F. Niche invasion, competition and coexistence amongst wild and domestic Bolivian populations of Chagas vector Triatoma infestans (Hemiptera, Reduviidae, Triatominae). C R Biol. 2013; 336(4): 183-93. https://doi.org/10.1016/j.crvi.2013.05.003.

32. Cecere MC, Vazquez-Prokopec GM, Gürtler RE, Kitron U. Spatio-temporal analysis of reinfestation by Triatoma infestans (Hemiptera: Reduviidae) following insecticide spraying in a rural community in northwestern Argentina. Am J Trop Med Hyg. 2004; 71(6): 803-10. https://doi.org/10.4269/ajtmh.2004.71.803

33. Abrahan LB, Gorla DE, Catalá SS. Dispersal of Triatoma infestans and other Triatominae species in the arid Chaco of Argentina — Flying, walking or passive carriage? The importance of walking females. Mem Inst Oswaldo Cruz. 2011; 106(2): 232-9. https:// doi.org/10.1590/S0074-02762011000200019.

34. Vazquez-Prokopec GM, Ceballos LA, Kitron U, Gürtler RE. Active dispersal of Natural Populations of Triatoma infestans (Hemiptera: Reduviidae) in Rural Northwestern Argentina. J Med Entomol. 2004; 41(4): 614-21. https://doi.org/10.1603/0022-2585-41.4.614.

35. Noireau F, Cortez MR, Monteiro FA, Jansen AM, Torrico F. Can wild Triatoma infestans foci in Bolivia jeopardize Chagas disease control efforts? Trends Parasitol. 2005; 21(1): 7-10. https://doi. org/10.1016/j.pt.2004.11.001.

Mem Inst Oswaldo Cruz, Rio de Janeiro, VOLUME 121 | 2026

Research Articles

Coexistence of monogamy and polygyny in Triatoma infestans: fine-scale genealogical structure reveals complex social structures within domestic colonies in the Bolivian Chaco

Alex Juan Cornejo Pinto^1,2,+, Rolando Sánchez^2†, Frédéric Lardeux³

¹Pan American Health Organisation/World Health Organization, La Paz, Bolivia
²Universidad Mayor de San Andrés, Instituto de Biología Molecular, La Paz, Bolivia
³Institut de Recherche pour le Développement, France

DOI: 10.1590/0074-02760250355

632 views 529 downloads

Print PDF Supplementary data

ABSTRACT

BACKGROUND Persistent reinfestation of Triatoma infestans in the Gran Chaco undermines Chagas disease (CD) control. While insecticide resistance is a known factor, the fine-scale social and demographic structure of vector colonies remains poorly understood.
OBJECTIVES To analyse the micro-geographic genetic structure, mating systems, and demographic history of T. infestans in a rural community in the Bolivian Chaco.
METHODS We genotyped 381 individuals from three neighbouring structures (domiciliary and peridomestic) using eight highly polymorphic microsatellite loci (expected heterozygosity, H_E = 0.675). Genealogical relationships were reconstructed using maximum likelihood (ML) analysis (COLONY), and demographic history was inferred through heterozygosity tests.
FINDINGS The infestation comprised 42 distinct full-sibling families nested within a single colony. We observed a stark dichotomy: two dominant families (> 80 individuals) exhibited monogamy and signs of distinct demographic histories (one in expansion, one recovering from a bottleneck), while 40 minor families showed high promiscuity (polygyny/polyandry). Finite growth rates varied significantly (λ = 1.03 vs 1.22), evidencing active intra-colonial competition.
MAIN CONCLUSIONS Domestic populations are not random aggregates, but complex mosaics of coexisting lineages with different adaptive strategies. The dominance of monogamous families suggests a priority effect advantage, while the “tail” of promiscuous minor families represents a cryptic reservoir. Effective control must account for this structural resilience, as surviving minor lineages could rapidly recolonise the niche.

key words: Chagas disease Triatoma infestans genetic structure mating systems vector control Bolivia

REFERENCES