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Dangerous appetite: The impact of Trypanosoma cruzi infection on the feeding and defecation behaviors of Triatoma dimidiata sensu lato (Latreille, 1811)

  • Irving Jesús May-Concha ,

    Roles Conceptualization, Data curation, Formal analysis, Investigation, Methodology, Software, Supervision, Validation, Visualization, Writing – original draft, Writing – review & editing

    irving.may@correo.uady.com.mx (IJMC); etienne.waleckx@ird.fr, etienne.waleckx@correo.uady.mx (EW)

    Affiliation Laboratorio de Parasitología, Centro de Investigaciones Regionales “Dr. Hideyo Noguchi”, Universidad Autónoma de Yucatán, Mérida, México

  • Víctor Andrés Garrido-González,

    Roles Data curation, Formal analysis, Investigation, Methodology, Writing – review & editing

    Affiliation Laboratorio de Parasitología, Centro de Investigaciones Regionales “Dr. Hideyo Noguchi”, Universidad Autónoma de Yucatán, Mérida, México

  • Guadalupe Ivette Hernández-Bolio,

    Roles Methodology, Writing – review & editing

    Affiliation Laboratorio de Parasitología, Centro de Investigaciones Regionales “Dr. Hideyo Noguchi”, Universidad Autónoma de Yucatán, Mérida, México

  • Mirely del Carmen Franco-Sosa,

    Roles Methodology, Writing – review & editing

    Affiliation Laboratorio de Parasitología, Centro de Investigaciones Regionales “Dr. Hideyo Noguchi”, Universidad Autónoma de Yucatán, Mérida, México

  • Joel Israel Moo-Millan,

    Roles Formal analysis, Writing – review & editing

    Affiliation Laboratorio de Parasitología, Centro de Investigaciones Regionales “Dr. Hideyo Noguchi”, Universidad Autónoma de Yucatán, Mérida, México

  • Etienne Waleckx

    Roles Formal analysis, Funding acquisition, Project administration, Resources, Writing – review & editing

    irving.may@correo.uady.com.mx (IJMC); etienne.waleckx@ird.fr, etienne.waleckx@correo.uady.mx (EW)

    Affiliations Laboratorio de Parasitología, Centro de Investigaciones Regionales “Dr. Hideyo Noguchi”, Universidad Autónoma de Yucatán, Mérida, México, INTERTRYP, Univ Montpellier, Cirad, IRD, Montpellier, France, ACCyC, Asociación Chagas con Ciencia y Conocimiento, A. C., Orizaba, Veracruz, México

Abstract

Background

Trypanosoma cruzi, the causative agent of Chagas disease, is primarily transmitted through the infected feces of blood-sucking bugs known as triatomines. As a result, its transmission is closely linked to the feeding and defecation behaviors of these insects. T. cruzi can alter various physiological processes in its vectors, including those involved in parasite acquisition, development, and excretion. This study aimed to assess the feeding and defecation behaviors of Triatoma dimidiata sensu lato (Latreille,1811), one of the main vectors, in relation to its T. cruzi infection status.

Methodology/Principal findings

Using both T. cruzi-infected and uninfected T. dimidiata, we measured various variables related to feeding and defecation behaviors. Notably, infected insects reached their host four times faster and began defecating twice as quickly as uninfected ones (282 ± 58 s vs. 1132 ± 198 s; 580 ± 120 s vs. 1220 ± 166 s, respectively), and these differences were significant. Among the bugs that defecated, 89% (16/18) of infected insects and 70% (14/20) of uninfected insects defecated during feeding. Moreover, among the bugs that defecated, a significantly higher proportion of infected insects defecated within the first 10 minutes after the start of feeding (11/18 = 61%) compared to uninfected insects, in which this behavior was less frequent (5/20 = 25%) and occurred later. Additionally, infected insects presented a significantly greater blood meal intake and feeding rate.

Conclusions/Significance

Overall, these findings suggest that T. cruzi alters the feeding and defecation behaviors of T. dimidiata in a way that could enhance its transmission potential.

Author summary

Chagas disease is a major public health concern in Latin America. It is caused by the parasite Trypanosoma cruzi, which is primarily transmitted when infected triatomine bugs defecate during or shortly after feeding on a host, depositing the parasite-laden feces on the host’s skin. The parasite can then enter the host’s organism through mucous membranes or skin lesions. This kind of transmission is known as stectorarian transmission. As such, certain aspects of feeding and defecation behaviors of triatomines, such as the elapsed time between the start of feeding and the start of defecation, play a crucial role in transmission. A vector that defecates on the host during or immediately after feeding increases the likelihood of parasite deposition on the skin, facilitating infection, compared to a vector that defecates after it left the vicinity of the host. Additionally, it is well known that some pathogens can manipulate their vectors by modifying various of their behaviors to enhance transmission likelihood. In this study, we investigated whether T. cruzi infection influences the feeding and defecation behaviors of Triatoma dimidiata, the major vector of Chagas disease in Southeastern Mexico, in a way that could enhance its transmission potential. Our results show that infected bugs detect their feeding host more quickly, feed more efficiently, and defecate sooner than uninfected bugs. These behavioral changes may enhance parasite transmission, suggesting a potential case of parasite-driven manipulation. Understanding these effects could help refine vector control strategies and improve Chagas disease prevention efforts.

Introduction

Trypanosoma cruzi, the causative agent of Chagas disease in humans, is primarily transmitted by blood-sucking insects of the subfamily Triatominae (Hemiptera: Reduviidae) and circulates among wild, synanthropic, and domestic mammalian hosts [1]. Vectorial transmission occurs when the feces of an infected insect come into contact with mucous membranes or damaged skin of its mammalian blood-feeding host. This typically happens during or immediately after blood feeding, as the insect defecates near the bite site, allowing T. cruzi to enter the host’s body [2].

Consequently, feeding and defecation behaviors are a critical part of vectorial capacity, as they directly influence the likelihood of T. cruzi transmission. The probability of the parasites contained in the feces coming into contact with and infecting a host depends on several parameters of these behaviors, such as feeding duration, number of bites during feeding, timing and number of defecations, and the distance from the host at which the first post-feeding defecation occurs. These factors define an efficient T. cruzi vector and can significantly impact the epidemiology of Chagas disease [3]. Studies on various triatomine species have shown that those exhibiting prolonged feeding behavior, performing a higher number of bites, and defecating during or shortly after blood feeding, particularly while still on or near the host, have an increased likelihood of transmitting T. cruzi, thereby enhancing their vectorial capacity [39].

Additionally, parasites can modify different physiological, behavioral, and morphological traits of their hosts [10]. These modifications may result from adaptive manipulation by the parasites to enhance their transmission, an adaptative response of the host to the infection, or merely a by-product of the infection that, under certain circumstances, can fortuitously favor parasite transmission [1113]. In this regard, a growing corpus of studies suggests that T. cruzi modifies different characteristics of its vectors, including their behaviors, physiology, and life-history traits [10,11]. Similarly, previous studies indicate that triatomines may experience modifications in their feeding and defecation behaviors when infected with T. cruzi [14]. For example, Botto-Mahan et al. [15] found that infected Mepraia spinolai detect their blood-feeding host almost twice as fast as uninfected bugs, bite twice more often, and begin defecation earlier. Pereyra et al. [16] reported that T. cruzi-infected T. infestans defecate twice as fast and in greater quantities than their uninfected counterparts. Chacón et al. [17], in the same species, demonstrated that infected bugs detect their blood-feeding host twice as fast as uninfected bugs, that the number of bites is increased from 4.5 bites in uninfected bugs to 8 bites in infected bugs, and that the time to first defecation is reduced by half in infected bugs. Besides, a significant correlation was found between the parasite load and the behavioral changes observed in infected triatomines [17]. Recently, Killets et al. [18] reported higher defecation index (DI), that the authors defined as DI = (% of insects that defecated up to 10 min post feeding X average number of defecations up to 10 min post feeding)/100, in T. cruzi-infected R. prolixus, T. sanguisuga, and T. gerstaeckeri compared to their uninfected counterparts. In the same way, the blood-meal size (volume of blood ingested) and gain weight of T. cruzi-infected R. prolixus and T. sanguisuga, were higher compared to their uninfected counterparts, while for T. gerstaeckeri, this depended on the infecting T. cruzi strain. In contrast, Takano-Lee and Edman [19] did not find differences between infected and uninfected R. prolixus regarding the number of feeding attempts, feeding time, time to the first fecal drop, or number of fecal drops, and D’Alessandro and Mandel [20] reported that T. cruzi-infected Rhodnius prolixus take blood meals almost twice less frequently as their uninfected counterparts.

Triatoma dimidiata (Latreille, 1811) is one of the main vectors of T. cruzi, with a wide geographic range extending from Mexico to northern Peru [21]. It is in fact a complex including different genetic lineages [2224], referred to as T. dimidiata sensu lato [23]. Two new cryptic species belonging to this complex have been recently proposed: T. mopan [25] and T. huehuetenanguensis [26]. Like other triatomines, T. dimidiata sensu lato displays diverse behaviors, including, among others, aggregation [27], alarm and defensive responses [28], host-seeking [29], feeding and defecation patterns [30], and mating behaviors [31]. However, research comparing these behaviors between T. cruzi-infected and uninfected T. dimidiata remains limited. In recent years, our group has been investigating the characteristics of T. cruzi infection status in T. dimidiata sensu lato. For example, we found that naturally infected T. dimidiata have a higher number of antennal receptors compared to uninfected bugs [32]. Additionally, we have observed that T. cruzi infection influences both aggregation and host-seeking behaviors, potentially increasing the likelihood of transmission [33,34]. However, there is no previous report comparing the feeding and defecation behaviors of T. cruzi-infected and uninfected T. dimidiata.

In this study, we evaluated the feeding and defecation behaviors in both infected and uninfected T. dimidiata and assessed potential differences associated with T. cruzi infection status. We tested the hypothesis that T. cruzi infection impacts the feeding and defecation behaviors of T. dimidiata in a way that enhances transmission potential.

Materials and methods

Ethics statement

The study was conducted in compliance with ethical standards and was approved by the Institutional Bioethics Committee of the Autonomous University of Yucatan, which reviewed and authorized the protocol for animal care and use. Mice and pigeons used as blood sources for triatomines were handled under Mexican national guidelines (NORMA Oficial Mexicana NOM-062-ZOO-1999, http://www.fmvz.unam.mx/fmvz/ principal/archivos/062ZOO.PDF) for animal care and use. Their care included continuous monitoring by qualified professionals, dietary supplementation with iron and multivitamins, and a scheduled use plan based on insect populations needs. No endangered or protected species were used for this study.

Insects

Second-instar nymphs of T. dimidiata were obtained from a colony maintained at the Parasitology Laboratory of the Regional Research Center Dr. Hideyo Noguchi, Autonomous University of Yucatan. The colony is reared under controlled conditions of 27 ± 1 °C, 70 ± 10% relative humidity (RH), and a 12: 12 h (L: D) photoperiod. The insects are fed on immobilized pigeons (Columba livia) between once and three times a week, depending on the experimental requirements of our laboratory. The specimens used in this study came from the fifth laboratory generation of this colony, which originated from T. dimidiata individuals collected in rural human dwellings in Yucatan, Southeastern Mexico, and belonging to haplogroup 1 [28], equivalent to ITS-2 group 3 of Bargues et al. [22], later proposed as T. huehuetenanguensis by Lima-Cordón et al. [26]. Therefore, any reference to T. dimidiata in this manuscript should be interpreted as referring to the species complex T. dimidiata sensu lato (Latreille, 1811).

Trypanosoma cruzi

For infection of triatomines, the “H1 strain”, a TcI strain of T. cruzi (NCBI BioProject accession number PRJNA880352), originally isolated from human and maintained in the laboratory by cyclical passages in BALB/c adult mice, was used.

Insect infection with Trypanosoma cruzi

After a two-week starvation period, the initial infection of the triatomines was carried out in nymphs that had molted to their third instar. The nymphs were fed ad libitum on different BALB/c mice (Fig 1A), each previously inoculated with the same T. cruzi inoculum. Inoculations were performed 15 days before triatomine feeding, ensuring that all mice were in the exponential growth phase of the parasite according to previous studies carried out in our laboratory [32,35]. Before feeding the nymphs, each mouse was anesthetized following intramuscular injection of a Xylazine–Ketamine mixture (10 mg and 100 mg per kg, respectively). Approximately 30 days after infection, fecal samples were obtained from each bug by gently compressing the terminal abdominal segment with tweezers (Fig 1B). Collected fecal samples were diluted in saline solution containing 0.05% EDTA. The infection status was confirmed by examining the samples under a light microscope at 400 × magnification and observing motile, flagellated parasites. The the number of parasites was quantified using a Neubauer counting chamber. Parasite loads in infected insects ranged from 1.5x106 to 2.5x106 parasites mL−1 of feces. The control group was fed under the same conditions using uninfected mice. The nymphs from both groups were then kept under rearing conditions and fed fortnightly on uninfected mice until they molted to the fifth instar. After molting, insects were starved for 10–15 days before being used in behavioral experiments. Two experimental groups were established: one consisting of T. cruzi-infected insects and the other of uninfected insects. Each experimental group included 20 insects.

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Fig 1. Key steps of the experimental procedure used in this study (A) Experimental infection of T. dimidiata third instar nymphs using anesthetized BALB/c mice.

(B) Collection of feces for parasitemia analysis. (C) Feeding device used for feeding and defecation behavior assessment.

https://doi.org/10.1371/journal.pntd.0013872.g001

Feeding and defecation patterns

Using a procedure previously reported by Lobbia et al. [36], each triatomine was individually weighed on an analytical balance (±0.0001 g) before being introduced into the experiment. Then, each insect was placed inside a transparent plastic container with a piece of folded paper positioned vertically to facilitate climbing (Fig 1C). After a 5-minute acclimation period, the open side of the container (covered with tulle mesh) was positioned under the ventral side of an immobilized pigeon, allowing the insects to feed ad libitum after climbing the folded paper. Time recording started immediately after the acclimation period. After feeding, each insect was carefully placed in a circular glass observation arena with a diameter of 15 cm, lined with filter paper at the bottom, and allowed to walk freely for one hour. Each insect was then weighted again, as well as the feces excreted during the assay. After each observation, the device was cleaned with detergent, chlorine, and alcohol and dried for 30 min to eliminate chemical cues that could affect subsequent assays. All assays were performed in an experimental room in a controlled environment maintained at 23 ± 1ºC and 37 ± 10% relative humidity during the scotophase. The illumination was provided by a 60-W red bulb positioned 120 cm above the arena, with a light intensity of 20 lux. Each pigeon was used for only one experimental session per day, and each triatomine was used only once. The experimenter was blinded to the infection status of each bug to eliminate potential observer bias in the results.

To analyze the feeding and defecation behaviors of T. dimidiata, the following previously proposed variables [7,16,17] were recorded for each triatomine: 1) host detection time, defined as the duration from when the triatomine begins to move and walks toward the host until it bites, indicated by the insertion of its rostrum into the pigeon’s skin; 2) number of bites, total number of bites performed during feeding; 3) blood meal intake, calculated by subtraction of the initial weight (weight of insect before feeding) from the final weight (the sum of weights of feces and the weight at the end of the assay); 4) feeding duration; 5) feeding rate, calculated by subtraction of the final weight from the initial weight, and dividing by the feeding duration; 6) time to first defecation after the start of feeding; 7) total number of defecations (feces and/or urine) recorded after the start of feeding; 8) proportion of insects that defecated during the assays; 9) proportion of them that defecated during feeding and 10) during the first ten minutes after the start of feeding.

Statistical analysis

To compare response variables between infected and uninfected groups, we used t-tests when the data followed a normal distribution as determined by Shapiro-Wilk tests [37]; otherwise, non-parametric Mann–Whitney U tests were applied. The proportions of insects that defecated during the assays, proportions of them that defecated during feeding, and within the first ten minutes after the start of feeding were compared using Fisher’s exact tests. All statistical analyses were performed in R 4.4 (Core Development Team, 2020). A significant level of P < 0.05 was used.

Results

Feeding behavior of T. dimidiata

In this section, data are presented as mean ± SEM. Overall, including both infected and uninfected insects, we found a mean host detection time of 707 ± 123 s (12 min), a mean number of bites per event of 4.6 ± 0.4, a mean blood meal intake of 0.29 ± 0.03 gr, a mean feeding duration of 1663 ± 139 sec (27.7 min), and a mean feeding rate of 0.2 mg/s ± 0.024 mg/s.

Both the infected and uninfected bug groups showed the same initial weight status before the experimental feeding with an average weight of 0.11 ± 0.01 g for both groups. This similarity helped avoid potential confusion related to bug size and fitness.

We observed no significant differences between experimental groups regarding the number of bites (4.0 ± 0.5 vs. 5.3 ± 0.5 for infected and uninfected bugs, respectively), or the feeding duration (1642 ± 211 s vs.1684 ± 187 s for infected and uninfected bugs, respectively) (Mann–Whitney U tests, P > 0.05, Table 1).

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Table 1. Summary values of the feeding and defecation behaviors according to T. cruzi infection status of T. dimidiata. Variable values are presented as mean ± SEM.

https://doi.org/10.1371/journal.pntd.0013872.t001

Strikingly, infected insects had a host detection time that was four times shorter than that of uninfected insects (282 ± 58 s vs. 1132 ± 198, respectively), and this difference was significant (U = 102, P = 0.002, Table 1). Additionally, infected insects showed a significantly higher blood meal intake (0.35 ± 0.05 vs. 0.22 ± 0.03 g, respectively, t = -2.48, df = 38, P = 0.019) (see Table 1 and Fig 2). Finally, infected insects showed a significantly higher feeding rate (0.26 ± 0.04 mg/s vs. 0.13 ± 0.01 mg/s, respectively, U = 315, P = 0.002, Table 1).

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Fig 2. Feeding behavior according to Trypanosoma cruzi infection status of Triatoma dimidiata.

(A) Host detection time, in seconds, for T. cruzi-infected and uninfected T. dimidiata. (B) Blood meal intake, in grams, for T. cruzi-infected and uninfected T. dimidiata. Significant differences between paired bars (Kruskall-Wallis test) are indicated by *P < 0.05, **P < 0.01. Error bars represent the standard error.

https://doi.org/10.1371/journal.pntd.0013872.g002

Defecation behavior of T. dimidiata

Overall, 38/40 (95%) of the insects defecated during the assays. The difference between groups was not statistically significant (18/20 = 90% for infected insects vs. 20/20 = 100% for uninfected insects, Fisher’s exact test, P = 0.487, Table 1). The insects that defecated during the assays began defecating between five and 2555 seconds after the start of feeding. Of them, infected bugs began defecating twice as fast as uninfected ones (580 ± 121 seg vs. 1220 ± 166 s, respectively, see Table 1 and Fig 3), and this difference was significant (U = 274, P = 0.006). However, no significant difference was observed in the total number of defecations when considering all the bugs used in the assays (3.9 ± 0.5 vs. 5.0 ± 0.6 for infected and uninfected bugs, respectively, t = -1.54, df = 38, P = 0.13, Table 1), or considering only the bugs that defecated during the assays (4.5 ± 0.5 vs. 5.0 ± 0.6 for infected and uninfected bugs, respectively, t = -1.01, df = 36, P = 0.32).

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Fig 3. Defecation behavior according to Trypanosoma cruzi infection status of Triatoma dimidiata.

Elapsed time between the start of feeding and the start of defecation, in seconds, for T. cruzi-infected and uninfected T. dimidiata. Significant differences between paired bars (Kruskall-Wallis test) are indicated by *P < 0.05, **P < 0.01. Error bars represent the standard error.

https://doi.org/10.1371/journal.pntd.0013872.g003

Among the insects that defecated during the assays, 16/18 (89%) of infected insects and 14/20 (70%) of uninfected insects defecated while feeding. Although this difference was not statistically significant (Fisher’s exact test, P = 0.238), the proportion that defecated within the first 10 minutes after the start of feeding was significantly higher in infected insects (11/18 = 61%) than in uninfected ones (5/20 = 25%) (Fisher’s exact test, P = 0.047, Table 1).

Discussion

In this study, we evaluated the feeding and defecation behaviors of T. dimidiata according to T. cruzi infection status, as these behaviors are key determinants of vectorial capacity and the likelihood of T. cruzi transmission [38]. Our study supports the hypothesis that T. cruzi infection alters the feeding and defecation behaviors of T. dimidiata in a way that increases the likelihood of parasite transmission, potentially as a result of vector manipulation by T. cruzi, as suggested in previous studies [15,39].

Firstly, we observed that infected T. dimidiata reached their blood-feeding host four times faster than uninfected bugs. A similar reduction in host detection time has been reported in infected M. spinolai and T. infestans [15,17,40], with infected individuals locating their hosts nearly twice as fast as uninfected ones [15,17]. These findings suggest that infection may influence the sensory biology and the host-seeking behavior in triatomines, including T. dimidiata [41,42]. Additionally, the increased number of certain antennal receptors in infected T. dimidiata, as previously reported [32], may enhance their ability to detect/identify potential blood-feeding hosts.

Secondly, while two infected bugs did not defecate during the assays, we did not find statistical difference in the proportion of bugs that defecated between the two groups (90% for infected bugs vs. 100% for uninfected bugs), and we found that, among those that did defecate, infected T. dimidiata began defecating twice as fast as uninfected bugs. Moreover, among the bugs that defecated, although the proportion that defecated during feeding was not significantly different between groups (80% for infected bugs vs. 70% for uninfected bugs), the proportion that defecated within the first 10 minutes after the start of feeding was significantly higher in infected bugs (61.1% vs. 25.0%). This finding has important implications, as the most efficient vectors are generally those that defecate during or immediately after feeding, thereby increasing the likelihood of infective feces coming into contact with the host [4,5,43,44].

Third, we found that the blood meal intake and the feeding rate were significantly higher in infected T. dimidiata compared to uninfected bugs. This finding aligns with previous studies on M. spinolai, T. rubrovaria, T, sanguisuga, and T. gerstaeckeri [15,18,45] and suggests that T. cruzi infection positively influences these feeding parameters. As previously proposed, a possible explanation is the competition for the nutrients in the ingested blood between the triatomine and T. cruzi [17].

Besides the differences observed between T. cruzi-infected and uninfected T. dimidiata, some measured parameters showed no significant differences between groups. Specifically, we found no differences in the number of bites or feeding duration. Our findings are consistent with those of Pereyra et al. [16] in T. infestans but differ from previous studies reporting that T. cruzi-infected R. prolixus, T. rubrovaria and T. infestans show changes in the number of bites and feeding duration [17,20,45]. One possible explanation is that fasting before the experiment influenced these results, as suggested by Pereyra et al. [16]. Alternatively, it is possible that T. cruzi infection does not affect these specific parameters in T. dimidiata.

Among the limitations of our study is the small sample size (n = 20 per group), which reduced the statistical power of our analyses, and may limit the generalizability of our findings. Nevertheless, our sample size was comparable to or even larger than those used in previous research investigating feeding and defecation patterns in triatomines [7,19,46]. Another factor that may limit the generalizability of our results is that we tested only a single T. cruzi strain, whereas behavior effects may vary depending on the strain [18]. Additionally, the range of parasite loads in the insects could represent a potential limitation. However, in our study, parasitemia was relatively homogeneous across all insects, ranging from 1.5 to 2.5 x 106 parasites mL−1 of feces. Although variation in parasite load can influence vector behavior, evidence from Chacón et al. [17] suggests that only large differences in infection intensity are likely to cause significant behavioral changes, indicating that the range observed here, remaining within the same order of magnitude, is unlikely to have biased our results. Finally, the variable starvation time experienced by the insects, which ranged from 10 to 15 days, could have influenced individual host-seeking and feeding behaviors. However, variable starvation time between bugs is a common feature of experimental studies with triatomines, as their highly variable molting times make it challenging to standardize the starvation period precisely before their use in experiments [16]. Moreover, previous studies indicate that starvation durations within the range of 10–15 days have no significant impact on the feeding responses of triatomines [47]. Therefore, it is reasonable to conclude that this range of starvation time is suitable for assessing differences in feeding behavior without introducing significant variability. Despite these limitations, our study lays the groundwork for further research to investigate, for example, the influence of parasite strain, parasite load, and starvation time on the feeding and defecation behaviors of T. dimidiata sensu lato.

Conclusions

The current work demonstrates that the TcI strain of T. cruzi used in this study modifies the feeding and defecation patterns of T. dimidiata, supporting the hypothesis that T. cruzi manipulates T. dimidiata to enhance its transmission potential. These findings have significant implications for transmission dynamics and should be considered to enhance understanding of the eco-epidemiology of T. cruzi infection and Chagas disease.

Supporting information

S1 Table. The complete dataset produced and analyzed in this study.

https://doi.org/10.1371/journal.pntd.0013872.s001

(XLSX)

Acknowledgments

We thank the Secretaría de Ciencia, Humanidades, Tecnología e Innovación (SECIHTI) for support to IJMC/ CVU: 272733. We also extend our gratitude to Pedro Pablo Martínez-Vega and Víctor Manuel Dzul-Huchim for their assistance with mouse handling.

References

  1. 1. Moo-Millan JI, Tu W, Montalvo-Balam TJ, Ibarra-López MP, Hernández-Betancourt S, May-Concha IJ, et al. Presence of Trypanosoma cruzi TcI and Trypanosoma dionisii in sylvatic bats from Yucatan, Mexico. Trans R Soc Trop Med Hyg. 2024.
  2. 2. Schuster JP, Schaub GA. Trypanosoma cruzi: skin-penetration kinetics of vector-derived metacyclic trypomastigotes. Int J Parasitol. 2000;30(14):1475–9. pmid:11428338
  3. 3. Diotaiuti L, Penido CM, Pires HHR, Días JCP. Dinâmica da alimentação do Triatoma sordida. Rev Soc Bras Med Trop. 1995;28:195–8.
  4. 4. Crocco LB, Catalá SS. Feeding and defaecation patterns in Triatoma sordida. Mem Inst Oswaldo Cruz. 1996;91(4):409–13. pmid:9070400
  5. 5. Rodríguez CS, Carrizo SA, Crocco LB. Comparison of feeding and defecation patterns between fifth-instar nymphs of Triatoma patagonica (Del Ponte, 1929) and Triatoma infestans (Klug, 1934) under laboratory conditions. Rev Soc Bras Med Trop. 2008;41(4):330–3. pmid:18853002
  6. 6. Padilla N A, Moncayo AL, Keil CB, Grijalva MJ, Villacís AG. Life Cycle, Feeding, and Defecation Patterns of Triatoma carrioni (Hemiptera: Reduviidae), Under Laboratory Conditions. J Med Entomol. 2019;56(3):617–24. pmid:30768666
  7. 7. López AG, Cardozo M, Oscherov EB, Crocco LB. Dynamics of feeding and defecation behavior of Triatoma infestans hybrids. Parasitol Res. 2020;119(9):2775–81. pmid:32737590
  8. 8. Nogueda-Torres B, Cervantes-Hernández F, Grant-Guillén Y, Michel-Parra JG, Martínez-Ibarra JA. Period of time and movement distances between feeding and postfeeding defecation in Triatoma pallidipennis (Heteroptera: Reduviidae). Acta Trop. 2025;263:107563. pmid:40015423
  9. 9. Nogueda-Torres B, Montañez-Valdez OD, Michel-Parra JG, Martínez-Grant DM, Martínez-Ibarra JA. Biological Parameters of Three Populations of Triatoma dimidiata s. s. (Hemiptera: Reduviidae) From Western Mexico. J Med Entomol. 2021;58(6):2114–23. pmid:34224558
  10. 10. Córdoba-Aguilar A. Chagas bugs and trypanosoma cruzi: Puppets and puppeteer? Acta Trop. 2020;211:105600. pmid:32592685
  11. 11. Poulin R. Parasite manipulation of host behavior: an update and frequently asked questions. Advances in the Study of Behavior. 2010;41:151–86.
  12. 12. Libersat F, Delago A, Gal R. Manipulation of host behavior by parasitic insects and insect parasites. Annu Rev Entomol. 2009;54:189–207. pmid:19067631
  13. 13. Schaub GA. An Update on the Knowledge of Parasite-Vector Interactions of Chagas Disease. Res Rep Trop Med. 2021;12:63–76. pmid:34093053
  14. 14. Schaub GA. Interaction of Trypanosoma cruzi, Triatomines and the Microbiota of the Vectors-A Review. Microorganisms. 2024;12(5):855. pmid:38792688
  15. 15. Botto-Mahan C, Cattan PE, Medel R. Chagas disease parasite induces behavioural changes in the kissing bug Mepraia spinolai. Acta Trop. 2006;98(3):219–23. pmid:16780784
  16. 16. Pereyra N, Lobbia PA, Mougabure-Cueto G. Effects of the infection with Trypanosoma cruzi on the feeding and excretion/defecation patterns of Triatoma infestans. Bull Entomol Res. 2019;24:1–8.
  17. 17. Chacón F, Bacigalupo A, Álvarez-Duhart B, Cattan PE, Solís R, Muñoz-San Martín C. The Parasite Load of Trypanosoma cruzi Modulates Feeding and Defecation Patterns of the Chagas Disease Vector Triatoma infestans. Microorganisms. 2022;10(5):1003. pmid:35630447
  18. 18. Killets KC, Wormington J, Zecca I, Chaves LF, Hamer GL, Hamer SA. Comparative Feeding and Defecation Behaviors of Trypanosoma cruzi-Infected and Uninfected Triatomines (Hemiptera: Reduviidae) from the Americas. Insects. 2025;16(2):188. pmid:40003818
  19. 19. Takano-Lee M, Edman JD. Lack of manipulation of Rhodnius prolixus (Hemiptera: Reduviidae) vector competence by Trypanosoma cruzi. J Med Entomol. 2002;39(1):44–51. pmid:11931271
  20. 20. D’Alessandro A, Mandel S. Natural infections and behavior of Trypanosoma rangeli and Trypanosoma cruzi in the vector Rhodnius prolixus in Colombia. J Parasitol. 1969;55(4):846–52. pmid:4980776
  21. 21. Dorn PL, Monroy C, Curtis A. Triatoma dimidiata (Latreille, 1811): a review of its diversity across its geographic range and the relationship among populations. Infect Genet Evol. 2007;7:343–52.
  22. 22. Bargues MD, Klisiowicz DR, Gonzalez-Candelas F, Ramsey JM, Monroy C, Ponce C, et al. Phylogeography and genetic variation of Triatoma dimidiata, the main Chagas disease vector in Central America, and its position within the genus Triatoma. PLoS Negl Trop Dis. 2008;2(5):e233. pmid:18461141
  23. 23. Dorn PL, de la Rúa NM, Axen H, Smith N, Richards BR, Charabati J, et al. Hypothesis testing clarifies the systematics of the main Central American Chagas disease vector, Triatoma dimidiata (Latreille, 1811), across its geographic range. Infect Genet Evol. 2016;44:431–43. pmid:27496718
  24. 24. Justi SA, Cahan S, Stevens L, Monroy C, Lima-Cordón R, Dorn PL. Vectors of diversity: Genome wide diversity across the geographic range of the Chagas disease vector Triatoma dimidiata sensu lato (Hemiptera: Reduviidae). Mol Phylogenet Evol. 2018;120:144–50. pmid:29248626
  25. 25. Dorn PL, Justi SA, Dale C, Stevens L, Galvão C, Lima-Cordón R, et al. Description of Triatoma mopan sp. n. from a cave in Belize (Hemiptera, Reduviidae, Triatominae). Zookeys. 2018;(775):69–95. pmid:30057472
  26. 26. Lima-Cordón RA, Monroy MC, Stevens L, Rodas A, Rodas GA, Dorn PL, et al. Description of Triatoma huehuetenanguensis sp. n., a potential Chagas disease vector (Hemiptera, Reduviidae, Triatominae). Zookeys. 2019;820:51–70.
  27. 27. Galvez-Marroquin Z, Cruz-López L, Malo EA, Ramsey JM, Rojas JC. Behavioural and electrophysiological responses of Triatoma dimidiata nymphs to conspecific faecal volatiles. Med Vet Entomol. 2018;32:102–10.
  28. 28. May-Concha I, Rojas JC, Cruz-López L, Ibarra-Cerdeña CN, Ramsey JM. Volatile compound diversity and conserved alarm behaviour in Triatoma dimidiata. Parasit Vectors. 2015;8:84. pmid:25656170
  29. 29. Waleckx E, Pasos-Alquicira R, Ramírez-Sierra MJ, Dumonteil E. Sleeping habits affect access to host by Chagas disease vector Triatoma dimidiata. Parasit Vectors. 2016;9(1):568. pmid:27809930
  30. 30. Zeledón R, Alvarado R, Jirón LF. Observations on the feeding and defecation patterns of three triatomine species (Hemiptera: Reduviidae). Acta Trop. 1977;34(1):65–77. pmid:16468
  31. 31. May-Concha I, Rojas JC, Cruz-López L, Millar JG, Ramsey JM. Volatile compounds emitted by Triatoma dimidiata, a vector of Chagas disease: chemical analysis and behavioural evaluation. Med Vet Entomol. 2013;27(2):165–74. pmid:23205718
  32. 32. May-Concha IJ, Escalante-Talavera MJ, Dujardin JP, Waleckx E. Does Trypanosoma cruzi (Chagas, 1909) (Kinetoplastida: Trypanosomatidae) modify the antennal phenotype of Triatoma dimidiata (Latreille, 1811) (Hemiptera: Triatominae)? Parasites & Vectors. 2022;14:466.
  33. 33. Uc-Diaz SS. Efecto de Trypanosoma cruzi sobre la selección de hospederos sanguíneos por Triatoma dimidiata. BcB Thesis. Universidad Autónoma de Yucatán, Campus de Ciencias Biológicas y Agropecuarias. 2020. p. 65.
  34. 34. Franco-Sosa MC. Comportamiento de agregación de Triatoma dimidiata a heces infectadas y no infectadas con Trypanosoma cruzi. BcB Thesis. Instituto Tecnologico de Conkal; 2025. p. 74.
  35. 35. Dumonteil E, Escobedo-Ortegon J, Reyes-Rodriguez N, Arjona-Torres A, Ramirez-Sierra MJ. Immunotherapy of Trypanosoma cruzi infection with DNA vaccines in mice. Infect Immun. 2004;72(1):46–53. pmid:14688079
  36. 36. Lobbia P, Calcagno J, Mougabure-Cueto G. Excretion/defecation patterns in Triatoma infestans populations that are, respectively, susceptible and resistant to deltamethrin. Med Vet Entomol. 2018;32(3):311–22. pmid:29430671
  37. 37. Sokal RR, Rohlf FJ. Introduction to biostatistics. 2nd ed. New York: Dover Publications Inc; 2009. p. 384.
  38. 38. Loza-Murguía M, Noireau F. Vectorial capacity of Triatoma guasayana (Wygodzinsky & Abalos) (Hemiptera: Reduviidae) compared with two other species of epidemic importance. Neotrop Entomol. 2010;39(5):799–809. pmid:21120391
  39. 39. Ramírez-González MG, Flores-Villegas AL, Salazar-Schettino PM, Gutiérrez-Cabrera AE, Rojas-Ortega E, Córdoba-Aguilar A. Zombie bugs? Manipulation of kissing bug behavior by the parasite Trypanosoma cruzi. Acta Trop. 2019;200:105177. pmid:31539526
  40. 40. Estay-Olea D, Correa JP, de Bona S, Bacigalupo A, Quiroga N, San Juan E, et al. Trypanosoma cruzi could affect wild triatomine approaching behaviour to humans by altering vector nutritional status: A field test. Acta Trop. 2020;210:105574. pmid:32504588
  41. 41. Marliére NP, Latorre-Estivalis JM, Lorenzo MG, Carrasco D, Alves-Silva J, Rodrigues J de O, et al. Trypanosomes Modify the Behavior of Their Insect Hosts: Effects on Locomotion and on the Expression of a Related Gene. PLoS Negl Trop Dis. 2015;9(8):e0003973. pmid:26291723
  42. 42. Barrozo RB, Reisenman CE, Guerenstein P, Lazzari CR, Lorenzo MG. An inside look at the sensory biology of triatomines. J Insect Physiol. 2017;97:3–19. pmid:27840287
  43. 43. Trumper EV, Gorla DE. Density-dependent timing of defaecation by Triatoma infestans. Trans R Soc Trop Med Hyg. 1991;85(6):800–2. pmid:1801360
  44. 44. Oliveira PL, Genta FA. Blood digestion in triatomine insects. In: Guarneri A, Lorenzo M, editors. Triatominae—The biology of Chagas disease vectors. Cham: Springer International Publishing; 2021. p. 265–84.
  45. 45. Verly T, Costa S, Lima N, Mallet J, Odêncio F, Pereira M, et al. Vector competence and feeding-excretion behavior of Triatoma rubrovaria (Blanchard, 1843) (Hemiptera: Reduviidae) infected with Trypanosoma cruzi TcVI. PLoS Negl Trop Dis. 2020;14(e0008712).
  46. 46. Braga MV, Lima MM. Feeding and defecation patterns of nymphs of Triatoma rubrofasciata (De Geer, 1773) (Hemiptera: Reduviidae), and its potential role as vector for Trypanosoma cruzi. Mem Inst Oswaldo Cruz. 1999;94:127–9.
  47. 47. Bodin A, Vinauger C, Lazzari CR. State-dependency of host-seeking in Rhodnius prolixus: The post-ecdysis time. J Exp Biol. 2009;212:2386–93.