DNA evidence of Trypanosoma cruzi in the Chilean wild vector Mepraia spinolai (Hemiptera: Reduviidae)

Botto‐Mahan, Carezza; Ortíz, Sylvia; Rozas, Marlene; Cattan, Pedro E.; Solari, Aldo

doi:10.1590/s0074-02762005000300003

Cited by 52 publications

(39 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Infection in earlier nymphal instars was rather high, indicating that insects became infected early during their lives, as described for T. infestans 49 and other triatomine species, 50 suggesting that they feed on vertebrate hosts infected with two or more T. cruzi lineages, which is frequent in nature. 14,23,51 We cannot discard the route of direct transmission between triatomines by coprophagy or cannibalism, 25,[52][53][54] given that all triatomines must obtain their symbionts at least once in their lifetime, probably by coprophagy.…”

Section: Discussionmentioning

confidence: 70%

Differential Pattern of Infection of Sylvatic Nymphs and Domiciliary Adults of Triatoma infestans with Trypanosoma cruzi Genotypes in Chile

Bacigalupo¹,

Segovia²,

García³

et al. 2012

The American Society of Tropical Medicine and Hygiene

Self Cite

View full text Add to dashboard Cite

Abstract. In Chile, the main vector of Chagas disease, Triatoma infestans, is under control after insecticide spraying. However, it has been found colonizing wild habitats. This study evaluated Trypanosoma cruzi infection of sylvatic and domiciliary T. infestans and identified their parasite genotypes. The sample studied was composed mainly of T. infestans sylvatic nymphs and domiciliary adults from a semi-urban area with human dwellings under vector control surveillance. Results showed prevalences of 57.7% in nymphs and 68.6% in adults. Hybridization tests showed a major T. cruzi lineage (TcI) circulating in sylvatic (93.3%) and domiciliary (100%) T. infestans. TcII, TcV, and TcVI were also detected, mainly in nymphs, suggesting differential adaptation of T. cruzi lineages among instars. We also discuss the origin of domiciliary individuals of T. infestans and the risk of human infection by triatomines of sylvatic foci that invade houses despite vector control programs.

show abstract

Section: Discussionmentioning

confidence: 70%

Differential Pattern of Infection of Sylvatic Nymphs and Domiciliary Adults of Triatoma infestans with Trypanosoma cruzi Genotypes in Chile

Bacigalupo¹,

Segovia²,

García³

et al. 2012

The American Society of Tropical Medicine and Hygiene

Self Cite

View full text Add to dashboard Cite

show abstract

“…14 Even though the human blood index for M. spinolai indicates that this species is not an important vector of T. cruzi , the insect reaches high population densities in stone walls or dry rivers near human dwellings, suggesting an increasing risk of Chagas disease transmission in these localities. 15 A previous study reported by Botto-Mahan and others 16 in the same geographic area showed 46.2% of T. cruzi infection in M. spinolai using molecular evidence, which is much higher than that reported for the same area using microscopic observation. In addition, their results indicate that younger nymphs are as infected as the older ones, therefore, equally important in parasite transmission.…”

Section: Introductionmentioning

confidence: 63%

Molecular Epidemiology of Chagas Disease in the Wild Transmission Cycle: The Evaluation in the Sylvatic Vector Mepraia spinolai from an Endemic Area of Chile

Coronado¹,

Rozas²,

Botto‐Mahan³

et al. 2009

The American Journal of Tropical Medicine and Hygiene

Self Cite

View full text Add to dashboard Cite

Abstract. The sylvatic transmission cycle of Chagas disease in Chile is composed of wild mammals and insects of the genus Mepraia . We determined infection rates and Trypanosoma cruzi genotypes in Mepraia spinolai . We collected 227 insects from two ecologically contrasting areas to assess T. cruzi infection. Polymerase chain reaction (PCR)-amplified minicircle DNAs were characterized by Southern blot and hybridization tests with genotype-specific probes. Infection in insects from the more fertile area was almost 2-fold higher than in the poorer area. The genotype TCI was the most prevalent and other genotypes such as TCIIb, TCIId, and TCIIe were found at lower rates. The areas differed in their genotype distribution but not in their genotype diversity. We suggest that the difference in abundance and richness of mammals between the areas may be producing the detected infection levels in vectors. Our results are compared with those reported for mammals from the same area.

show abstract

“…In Illapel, a first study found infection rates of 46-54%, 15 and a second survey in neighbored areas but two ecologically different sites gave rates of 40% and 76%. 18 The infection rate was higher in an area of higher vegetation cover, suggesting that M. spinolai in this ecotope has better opportunities to feed on wild animals and therefore, higher infection rates.…”

mentioning

confidence: 98%

“…15 In the national surveillance program of triatomine vectors, 11-47% of these species were infected. 16 Thus, the aim of this study is to determine T. cruzi infection in M. gajardoi and M. spinolai by assessing infection on insects under natural conditions (right after collection) and reassessing after feeding in the laboratory.…”

mentioning

confidence: 99%

Trypanosoma cruzi Infection in Mepraia gajardoi and Mepraia spinolai: The Effect of Feeding Nymphs from the Field

Egaña

Vergara

Campos

et al. 2014

The American Society of Tropical Medicine and Hygiene

Self Cite

View full text Add to dashboard Cite

Abstract. We evaluated Trypanosoma cruzi infection rates by means of minicircle DNA-based polymerase chain reactions (PCRs) in 70 starved Mepraia gajardoi from northern Chile and 65 M. spinolai from central Chile after feeding. Immediately after collection in the field, 20% of M. gajardoi were found infected; after feeding, 67% of the uninfected were infected. One group of M. spinolai seemed to be completely uninfected, but after the first and second feedings, 62% and 59% were positive, respectively.The protozoan Trypanosoma cruzi (Kinetoplastida Trypanosomatidae), etiologic agent of Chagas disease, is mainly transmitted to mammals by contamination of the skin lesions with triatomine insect feces with parasites.1 In a regularly fed infected triatomine, T. cruzi amplify as epimastigotes, which later, differentiate to trypomastigotes that are eliminated by the feces. Several biological factors modulate T. cruzi-insect vector interactions, including food supply, intestinal components, gut flora, T. cruzi strain, and insect physiology.2 The Triatominae subfamily is composed of 146 species distributed in 18 genera and grouped into six tribes.3,4 Important vectors rapidly defecate on the host. These vectors urinate/defecate during or after feeding from a rapid to a delayed behavior according the triatomine species.5 Several factors, such as the competition of enterobacteria of the flora and T. cruzi with its vector for nutrients, and thereby, feeding affect not only parasite density and insect molting but also, changes in the epimastigote/trypomastigote ratio in the rectum of Triatoma infestans (Hemiptera, Triatominae). 6 The rectal parasite density increases until several weeks post-infection with regular blood meals, reaching maximal values of several million parasites. The parasite density is only strongly influenced by very long starvation up to 20 weeks. [7][8][9] In the laboratory, the feeding status also modulated the olfactory host search behavior of triatomines.10 In Chile, the wild vector of Chagas disease is Mepraia spp. (Hemiptera, Triatominae), which is composed of three different species: M. gajardoi, M. spinolai, and M. parapatrica.11-13 M. gajardoi and M. spinolai are frequently found in corrals of domestic animals and stony hills and rock crevices of arid zones of the northern and semiarid areas of central Chile, respectively. Between 11% and 27% infections with T. cruzi were found in M. gajardoi.14 Infection rates in M. spinolai range from 46% to 54%. 15 In the national surveillance program of triatomine vectors, 11-47% of these species were infected. 16 Thus, the aim of this study is to determine T. cruzi infection in M. gajardoi and M. spinolai by assessing infection on insects under natural conditions (right after collection) and reassessing after feeding in the laboratory.In the laboratory overall, 70 M. gajardoi nymphs stages III-V from Vitor and 35 and 30 M. spinolai nymphs stages III-V from Illapel and Colina, respectively, were studied. The insects were maintained and fed individually inside ...

show abstract

DNA evidence of Trypanosoma cruzi in the Chilean wild vector Mepraia spinolai (Hemiptera: Reduviidae)

Cited by 52 publications

References 12 publications

Differential Pattern of Infection of Sylvatic Nymphs and Domiciliary Adults of Triatoma infestans with Trypanosoma cruzi Genotypes in Chile

Differential Pattern of Infection of Sylvatic Nymphs and Domiciliary Adults of Triatoma infestans with Trypanosoma cruzi Genotypes in Chile

Molecular Epidemiology of Chagas Disease in the Wild Transmission Cycle: The Evaluation in the Sylvatic Vector Mepraia spinolai from an Endemic Area of Chile

Trypanosoma cruzi Infection in Mepraia gajardoi and Mepraia spinolai: The Effect of Feeding Nymphs from the Field

Contact Info

Product

Resources

About