1
|
Alevi KCC, Garcia ACC, Guerra AL, Moreira FFF, de Oliveira J, Aristeu da Rosa J, de Azeredo Oliveira MTV. Triatoma vitticeps (Stal, 1859) (Hemiptera, Triatominae): A Chagas Disease Vector or a Complex of Vectors? Am J Trop Med Hyg 2018; 99:954-956. [PMID: 30141391 PMCID: PMC6159607 DOI: 10.4269/ajtmh.17-0512] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 01/29/2018] [Indexed: 11/07/2022] Open
Abstract
Triatoma vitticeps is a Chagas disease vector that was found infected with Trypanosoma cruzi in homes. As this species is endemic from Brazil (Bahia, Espírito Santo, Minas Gerais, and Rio de Janeiro) and no study comparing the specimens from different Brazilian states was conducted, we analyzed the genetic distance (16S rDNA, Cyt b, and COI mitochondrial genes) and the chromosomal characteristics for T. vitticeps from Minas Gerais, Rio de Janeiro, and Espírito Santo. All specimens showed the same cytogenetic characteristics. On the other hand, the different mitochondrial genes demonstrated high intraspecific variation between the genetic distances of T. vitticeps from different states ranging from 2.3% to 7.2%. Based on this, our results suggest that possibly what is characterized as T. vitticeps is a complex of cryptic species (or subspecies).
Collapse
Affiliation(s)
- Kaio Cesar Chaboli Alevi
- Laboratório de Biologia Celular, Departamento de Biologia, Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista “Júlio de Mesquita Filho”, São José do Rio Preto, São Paulo, Brazil
| | - Ariane Cristina Caris Garcia
- Laboratório de Biologia Celular, Departamento de Biologia, Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista “Júlio de Mesquita Filho”, São José do Rio Preto, São Paulo, Brazil
| | - Ana Letícia Guerra
- Laboratório de Biologia Celular, Departamento de Biologia, Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista “Júlio de Mesquita Filho”, São José do Rio Preto, São Paulo, Brazil
| | | | - Jader de Oliveira
- Laboratório de Parasitologia, Departamento de Ciências Biológicas, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista “Júlio de Mesquita Filho”, Araraquara, São Paulo, Brazil
| | - João Aristeu da Rosa
- Laboratório de Parasitologia, Departamento de Ciências Biológicas, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista “Júlio de Mesquita Filho”, Araraquara, São Paulo, Brazil
| | - Maria Tercília Vilela de Azeredo Oliveira
- Laboratório de Biologia Celular, Departamento de Biologia, Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista “Júlio de Mesquita Filho”, São José do Rio Preto, São Paulo, Brazil
| |
Collapse
|
2
|
Moreira OC, Verly T, Finamore-Araujo P, Gomes SAO, Lopes CM, de Sousa DM, Azevedo LR, da Mota FF, d’Avila-Levy CM, Santos-Mallet JR, Britto C. Development of conventional and real-time multiplex PCR-based assays for estimation of natural infection rates and Trypanosoma cruzi load in triatomine vectors. Parasit Vectors 2017; 10:404. [PMID: 28851417 PMCID: PMC5576278 DOI: 10.1186/s13071-017-2343-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Accepted: 08/22/2017] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Chagas disease is a complex anthropozoonosis with distinct domestic and sylvatic mammal species acting as potential reservoirs. The diversity of vector species and their habitats are among the factors that hinder the control of the disease. Control programs periodically monitor the prevalence of T. cruzi infection in insect bugs through microscopical observation of diluted feces. However, microscopy presents limited sensitivity in samples with low parasite numbers, difficulties in examining all evolutionary stages of the insect and may in turn be limited to differentiate T. cruzi from other morphologically similar trypanosomatids. Here, we report two highly sensitive and accurate methodologies to infer T. cruzi infection rates and to quantify parasite load in the gut of field-collected triatomines. METHODS Triatomines were manually collected in the period 2011-2012 and 2014-2015, in domestic, peridomestic or sylvatic habitats in rural areas of 26 municipalities, encompassing three distinct Brazilian biomes: Caatinga, Cerrado and Atlantic Rainforest. Following morphological and taxonomical identification, the search for flagellated protozoa was performed by optical microscopy. A conventional PCR targeting T. cruzi kDNA and a TaqMan qPCR directed to the parasite nuclear satellite DNA (SAT) were developed, both in multiplex, with the triatomine 12S subunit ribosomal RNA gene, used as internal amplification control. Both methods were used for detection (kDNA-PCR) and parasite load quantification (SAT-DNA-qPCR), to investigate T. cruzi infection in captured triatomines. RESULTS The combined methods were assayed on a panel of 205 field-collected triatomine samples. Diagnostic analysis revealed 21% positivity for the kDNA-PCR, whereas microscopic examination enabled identification of T. cruzi in only 7.0% of the PCR-positive samples. Negative PCR results were confirmed by the absence of T. cruzi flagellates using microscopy. Caatinga biome yielded the highest T. cruzi infection rate (60%), followed by the Atlantic Rainforest and Cerrado with 7.1 and 6.1%, respectively. In addition, a wide range distribution of parasite load, varying from 8.05 × 10-2 to 6.31 × 1010 was observed with a median of 2.29 × 103 T. cruzi/intestine units. When parasite load was analyzed by triatomine species, a significantly higher median was found for Panstrongylus lutzi in comparison with Triatoma brasiliensis. CONCLUSIONS Our results demonstrate highly sensitive PCR-based methodologies to monitor T. cruzi infection in triatomines. In addition, the qPCR assay offers the possibility of further evaluation parasite load, as a promising biomarker of the vectorial capacity of triatomines in Chagas disease endemic areas.
Collapse
Affiliation(s)
- Otacilio C. Moreira
- Laboratório de Biologia Molecular e Doenças Endêmicas, Instituto Oswaldo Cruz/Fiocruz, Rio de Janeiro, Brazil
| | - Thaiane Verly
- Laboratório de Biologia Molecular e Doenças Endêmicas, Instituto Oswaldo Cruz/Fiocruz, Rio de Janeiro, Brazil
| | - Paula Finamore-Araujo
- Laboratório de Biologia Molecular e Doenças Endêmicas, Instituto Oswaldo Cruz/Fiocruz, Rio de Janeiro, Brazil
| | - Suzete A. O. Gomes
- Laboratório de Biodiversidade de Parasitas e Vetores, Universidade Federal Fluminense/UFF, Rio de Janeiro, Niterói Brazil
| | - Catarina M. Lopes
- Laboratório Interdisciplinar de Vigilância Entomológica de Diptera e Hemiptera, Instituto Oswaldo Cruz/Fiocruz, Rio de Janeiro, Brazil
| | - Danielle M. de Sousa
- Laboratório Interdisciplinar de Vigilância Entomológica de Diptera e Hemiptera, Instituto Oswaldo Cruz/Fiocruz, Rio de Janeiro, Brazil
| | - Lívia R. Azevedo
- Laboratório de Biologia Molecular e Doenças Endêmicas, Instituto Oswaldo Cruz/Fiocruz, Rio de Janeiro, Brazil
| | - Fabio F. da Mota
- Laboratório de Biologia Computacional e Sistemas, Instituto Oswaldo Cruz/Fiocruz, Rio de Janeiro, Brazil
| | - Claudia M. d’Avila-Levy
- Laboratório de Estudos Integrados em Protozoologia, Instituto Oswaldo Cruz/Fiocruz, Rio de Janeiro, Brazil
| | - Jacenir R. Santos-Mallet
- Laboratório Interdisciplinar de Vigilância Entomológica de Diptera e Hemiptera, Instituto Oswaldo Cruz/Fiocruz, Rio de Janeiro, Brazil
| | - Constança Britto
- Laboratório de Biologia Molecular e Doenças Endêmicas, Instituto Oswaldo Cruz/Fiocruz, Rio de Janeiro, Brazil
| |
Collapse
|
3
|
Monte GLS, Tadei WP, Farias TM. Ecoepidemiology and biology of Eratyrus mucronatus Stål, 1859 (Hemiptera: Reduviidae: Triatominae), a sylvatic vector of Chagas disease in the Brazilian Amazon. Rev Soc Bras Med Trop 2015; 47:723-7. [PMID: 25626651 DOI: 10.1590/0037-8682-0263-2014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Accepted: 12/15/2014] [Indexed: 11/22/2022] Open
Abstract
INTRODUCTION Eratyrus mucronatus Stål, 1859 is a wild triatomine vector of Trypanosoma cruzi Chagas, 1909. However, little is known regarding the biology and ecoepidemiology of this triatomine in the Brazilian Amazon. The present study describes the biology of E. mucronatus grown under laboratory conditions and the epidemiological aspects of its natural breeding sites. METHODS Five colonies were monitored in the field for 3 years. Temperature and humidity measurements were taken in the mornings and afternoons at the natural breeding sites, and the behavior and distribution of the nymphs and adults were observed in the wild colony. We also monitored the life cycle under controlled laboratory conditions. RESULTS Some factors that were considered decisive for the establishment of these colonies were present at all of the colonies studied in the field. These factors included an active termite nest, a vertebrate for repast, and dry and shaded substrates with temperatures of 24-28°C and with humidity of 80-90%. A generation was developed in 274 days under these microclimatic conditions in the laboratory. CONCLUSIONS The climatic variables described in the field indicate that these environmental parameters have a limiting effect on the dispersal and colonization of E. mucronatus to new environments. In addition, the long period of development to adulthood demonstrates that only one generation can develop per year even under the more favorable laboratory conditions.
Collapse
Affiliation(s)
- Gersonval Leandro Silva Monte
- Laboratório de Malária e Dengue, Departamento de Ciências da Saúde, Instituto Nacional de Pesquisas da Amazônia, Manaus, AM, Brasil
| | - Wanderli Pedro Tadei
- Laboratório de Malária e Dengue, Departamento de Ciências da Saúde, Instituto Nacional de Pesquisas da Amazônia, Manaus, AM, Brasil
| | - Thaysa Marinho Farias
- Laboratório de Malária e Dengue, Departamento de Ciências da Saúde, Instituto Nacional de Pesquisas da Amazônia, Manaus, AM, Brasil
| |
Collapse
|
4
|
Cardozo-de-Almeida M, Neves SCT, Almeida CED, Lima NRCD, Oliveira MLRD, Santos-Mallet JRD, Gonçalves TCM. Biology of Triatoma carcavalloi Jurberg, Rocha & Lent, 1998 under laboratory conditions. Rev Soc Bras Med Trop 2014; 47:307-12. [DOI: 10.1590/0037-8682-0050-2014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Indexed: 11/22/2022] Open
|
5
|
Multiple mitochondrial genes of some sylvatic Brazilian Triatoma: non-monophyly of the T. brasiliensis subcomplex and the need for a generic revision in the Triatomini. INFECTION GENETICS AND EVOLUTION 2014; 23:74-9. [PMID: 24508245 DOI: 10.1016/j.meegid.2014.01.024] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Revised: 01/14/2014] [Accepted: 01/20/2014] [Indexed: 11/24/2022]
Abstract
Multiple fragments of mitochondrial DNA genes (cytochrome b, cytochrome oxidase I, and 16S rDNA) were used to evaluate the phylogenetic relationships among Triatoma melanocephala, Triatoma tibiamaculata, Triatoma vitticeps, and other members of Triatoma brasiliensis subcomplex under a Bayesian framework and maximum parsimony criterion. With the addition of new sequences of T. tibiamaculata and T. vitticeps, Triatoma juazeirensis, Triatoma melanica and the newly sequenced T. melanocephala, the three first sylvatic species, T. melanocephala, T. tibiamaculata and T. vitticeps, were strongly recovered into a clade separate from the other with the remaining Triatoma species from South America, such as the members of T. brasiliensis subcomplex. Panstrongylus megistus was recovered as a sister to T. tibiamaculata, whereas T. vitticeps was a sister to T. melanocephala. This study revealed the non-monophyly of the T. brasiliensis subcomplex, and the polyphyly of Triatoma was reinforced by the placement of these three sylvatic species with Dipetalogaster, Meccus, Mepraia, and Panstrongylus. The results herein shown highlight the need of generic revision in Triatomini.
Collapse
|
6
|
dos Santos CB, Leite GR, Sessa PA, Falqueto A. Dynamics of feeding and defecation in Triatoma vitticeps (Stal, 1859) (Hemiptera, Reduviidae, Triatominae) and its potential in the transmission of Trypanosoma cruzi. Mem Inst Oswaldo Cruz 2006; 101:543-6. [PMID: 17072459 DOI: 10.1590/s0074-02762006000500010] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2006] [Accepted: 05/16/2006] [Indexed: 11/22/2022] Open
Abstract
Adults of Triatoma vitticeps infected by flagellates similar to Trypanosoma cruzi are frequently captured by the inhabitants of rural areas in the Brazilian state of Espirito Santo. The dynamics of feeding and defecation were observed in three groups of adult triatomines, consisting of sylvatic T. vitticeps and laboratory-reared specimens of this species and T. infestans. Triatomines were observed from the moment they were presented with an immobilized chicken as a bloodmeal source until 240 min after feeding had ended. Mean times between the end of feeding and defecation for T. infestans, wild T. vitticeps and laboratory-reared specimens of the latter species were 1.2, 21.1, and 64 min respectively. All T. infestans defecated within 10 min of feeding, while only 29.9 of wild and 52.8% laboratory-reared specimens of T. vitticeps did so within this period. These results may explain the low efficiency of T. vitticeps in T. cruzi transmission to man. The shorter time between feeding and defecation in laboratory-reared T. vitticeps may indicate a change in behaviour of this species as a result of adaptation to an artificial environment.
Collapse
Affiliation(s)
- Claudiney Biral dos Santos
- Núcleo de Entomologia da Secretaria de Saúde do Estado do Espirito Santo, Universidade Federal do Espirito Santo, Av. Marechal Campos 1468, 29040-090 Vitória, ES, Brasil.
| | | | | | | |
Collapse
|
7
|
Almeida CE, Folly-Ramos E, Agapito-Souza R, Magno-Esperança G, Pacheco RS, Costa J. Triatoma rubrovaria (Blanchard, 1843) (Hemiptera-Reduviidae-Triatominae) IV: bionomic aspects on the vector capacity of nymphs. Mem Inst Oswaldo Cruz 2005; 100:231-5. [PMID: 16113859 DOI: 10.1590/s0074-02762005000300002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Triatoma rubrovaria has become the most frequently captured triatomine species since the control of T. infestans in the state of Rio Grande do Sul (RS), Brazil. The aim of this study was to evaluate aspects of the vectorial competence of T. rubrovaria using nymphs raised in laboratory under environmental conditions of temperature and humidity and fed on mice. The average developmental period of T. rubrovaria was 180.1 days. The percentage of defecation shortly after feeding was still higher than previous studies in which samples of T. rubrovaria subjected to a slight starvation period before the blood meal were used. The obtained results support former indication that T. rubrovaria presents bionomic characteristics propitious to be a good vector of Trypanosoma cruzi to man. Therefore its domiciliary invasion process must be continuously monitored.
Collapse
Affiliation(s)
- Carlos Eduardo Almeida
- Coleção Entomológica, Departamento de Entomologia, Instituto Oswaldo Cruz-Fiocruz, 21045-900 Rio de Janeiro, RJ, Brazil.
| | | | | | | | | | | |
Collapse
|
8
|
dos Santos CB, Ferreira AL, Leite GR, Ferreira GEM, Rodrigues AAF, Falqueto A. Peridomiciliary colonies of Triatoma vitticeps (Stal, 1859) (Hemiptera, Reduviidae, Triatominae) infected with Trypanosoma cruzi in rural areas of the state of Espírito Santo, Brazil. Mem Inst Oswaldo Cruz 2005; 100:471-3. [PMID: 16184222 DOI: 10.1590/s0074-02762005000500004] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
In Brazil, the colonization of human dwellings by triatomines occurs in areas with native vegetation of the caatinga or cerrado types. In areas of Atlantic forest such as in the Brazilian state of Espírito Santo, there are no species adapted to live in human habitations. The few autochthonous cases of Chagas disease encountered in Espírito Santo have been attributed to adult specimens of Triatoma vitticeps that invade houses from forest remnants. In recent years, the entomology unit of the Espírito Santo State Health Secretariat has recorded nymphs infected with flagellates similar to Trypanosoma cruzi in rural localities. Entomological surveys were carried out in the residences and outbuildings in which the insects were found, and serological examinations for Chagas disease performed on the inhabitants. Four colonies were found, all associated with nests of opossums (Didelphis aurita), 111 specimens of T. vitticeps, and 159 eggs being collected. All the triatomines presented flagellates in their frass. Mice inoculated with the faeces presented trypomastigotes in the circulating blood and groups of amastigotes in the cardiac muscle fibres. Serological tests performed on the inhabitants were negative for T. cruzi. Even with the intense devastation of the forest in Espírito Santo, there are no indications of change in the sylvatic habits of T. vitticeps. Colonies of this insect associated with opossum nests would indicate an expansion of the sylvatic environment into the peridomicile.
Collapse
|
9
|
Lorosa ES, Valente MVMP, Cunha V, Lent H, Jurberg J. [Source of Chagas disease in Arcádia, state of Rio de Janeiro, Brazil]. Mem Inst Oswaldo Cruz 2004; 98:885-7. [PMID: 14762512 DOI: 10.1590/s0074-02762003000700004] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Following the report of triatomine nymphs in a house in Arcadia, Miguel Pereira, state of Rio de Janeiro, Brazil, the infested dwelling was checked. Several eggs and 46 specimens of Triatoma vitticeps (Stal, 1859) were collected. Among them, adults and nymphal instars accounted for 43.5% and 56.5%, respectively. Analysis of blood meals showed the ecletism of this species; 24 (52.2%) were single feeds, 18 insects (39.1%) fed on two hosts and 4 (8.7%) on three hosts. Trypanosoma cruzi infection rate of examined specimens was 13%. Finally one of the residents of the house was positive for anti-T. cruzi antibodies using indirect immunofluorescence.
Collapse
Affiliation(s)
- Elias Seixas Lorosa
- Departamento de Entomologia, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, RJ, 21045-900, Brasil.
| | | | | | | | | |
Collapse
|
10
|
Guarneri AA, Diotaiuti L, Gontijo NF, Gontijo AF, Pereira MH. Blood-feeding performance of nymphs and adults of Triatoma brasiliensis on human hosts. Acta Trop 2003; 87:361-70. [PMID: 12875930 DOI: 10.1016/s0001-706x(03)00121-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The blood-feeding behaviour of nymphs and adults of Triatoma brasiliensis fed on the forearm of human volunteers was studied by electronic monitoring of the cibarial pump. Parameters of total contact time (TT), initial weight (IW), weight gain (WG), ingestion rate (IR), pump frequency (F), quantity of liquid ingested per cibarial pump stroke (QLC) and non-ingestive time (NIT) (cumulative probing time and pumping interruptions during blood feeding) were measured. Protein profile (SDS-PAGE) and quantity of proteins of salivary gland extracts (QP) were also determined for each stage. The TT reflects the feeding performance of the insects and differed between instars, varying between 18.3+/-2.5 min for the first instar and 33.9+/-2.3 min for the fifth instar. The observed increase in the IR when comparing different instars was related to the increase in the cibarial pump volume inferred from the QLC data. During development, the volume of the cibarial pump grew asymmetrically determining the different contact times observed among the instars. Males and females presented a remarkable sexual dimorphism in respect to the volume of the cibarial pump, females showing a better performance compared to males. Despite the differences, the results show that each of the development stages of T. brasiliensis was able to obtain a relatively fast bloodmeal, with few interruptions and without causing pain, providing further evidence of the capacity of this species to adapt to domestic environments.
Collapse
Affiliation(s)
- Alessandra A Guarneri
- Centro de Pesquisas René Rachou, Fiocruz, Caixa Postal 1743, 30190-002, Belo Horizonte, MG, Brazil.
| | | | | | | | | |
Collapse
|
11
|
Almeida CE, Francischetti CN, Pacheco RS, Costa J. Triatoma rubrovaria (Blanchard, 1843) (Hemiptera-Reduviidae-Triatominae) III: patterns of feeding, defecation and resistance to starvation. Mem Inst Oswaldo Cruz 2003; 98:367-71. [PMID: 12886416 DOI: 10.1590/s0074-02762003000300012] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Data from the Chagas Disease Control Program indicate a growing domiciliary and peridomiciliary invasion of Triatoma rubrovaria in the State of Rio Grande do Sul, where it has become the most frequent triatomine species captured there since the control of T. infestans. Bionomic characteristics that could influence the vectorial capacity of T. rubrovaria as vector of Trypanosoma cruzi were evaluated: patterns of (i) feeding, (ii) defecation, and (iii) resistance to starvation, using insects fed on mice. Fifty three percent of the females showed a defecation pattern conducive to chagasic transmission, defecating either on or near the bite site. The averages of the resistance to starvation varied from 48.1 to 179 days, for the first and fifth nymphal stages, respectively. Our study shows that with respect to the patterns of feeding, defecation and resistance to fasting, T. rubrovaria presented similar rates to the ones observed for other effective vector species, such as T. infestans. Thus, based on our studies we conclude that T. rubrovaria has biological characteristics that can positively influence its capacity to become infected and transmit T. cruzi, and also to keep residual populations after chemical control interventions.
Collapse
Affiliation(s)
- Carlos Eduardo Almeida
- Núcleo Avançado de Estudos de Vetores e Artrópodes Peçonhentos, Museu de Ciências Naturais, Centro Universitário de Barrra Mansa, Barra Mansa, RJ, Brasil.
| | | | | | | |
Collapse
|
12
|
Sessa PA, Pimentel RR, Ferreira AL, Falqueto A. [Chagas' disease seroprevalence among school-age children in Espírito Santo State, Brazil, 1999-2000]. CAD SAUDE PUBLICA 2002; 18:1765-9. [PMID: 12488904 DOI: 10.1590/s0102-311x2002000600031] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Although the Brazilian State of Espírito Santo is not considered endemic for Chagas' disease, the sylvatic triatomines occurring there frequently invade houses, increasing the chances of Trypanosoma cruzi transmission to man. The epidemiological pattern of the disease in Espírito Santo was evaluated by a serological survey of 5,243 schoolchildren ages 7 to 14 years, residents of 17 municipalities. Indirect immunofluorescence, indirect hemagglutination, and immunoenzymatic (ELISA) tests were positive in only one person, representing only 0.019% of the total. This result was similar to those found by other authors in previous studies. Based on the results of serological tests it is concluded that the epidemiological pattern of Chagas' disease in Espírito Santo remains stable, despite the intensive destruction of the Atlantic Forest that has occurred in recent decades.
Collapse
Affiliation(s)
- Paulo Augusto Sessa
- Unidade de Medicina Tropical, Departamento de Patologia, Centro Biomédico, Universidade Federal do Espírito Santo, Vitória, ES 29040-090, Brasil.
| | | | | | | |
Collapse
|
13
|
Moreira CJDC, Spata MCD. Dynamics of evolution and resistance to starvation of Triatoma vitticeps (Stal 1859) (Reduviidae: Triatominae), submitted to two different regimens of food deprivation. Mem Inst Oswaldo Cruz 2002; 97:1049-55. [PMID: 12471435 DOI: 10.1590/s0074-02762002000700020] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The resistance to starvation of Triatoma vitticeps has been analyzed comparatively, according to different regimens of food deprivation under laboratory conditions. One cohort, composed of 100 specimens of each evolutionary nymphal stage, was submitted to continuous fasting until death; the second group, arranged in the same way, was fed once on chicken. Through this work, it was possible not only to compare the results obtained from the first group with other authors' results but, also, to analyze the dynamics of evolution, molting, longevity and the increase in insect longevity, in the second group. The average values recorded for survival time revealed statistical differences between the two groups. Among the important results detected, there is one that deserves to be emphasized: the incredible increase in longevity among insects that received only one feed - an average increase in survival time that reached 2.95 to 3.30 times in nymphs of 3rd and 4th stages, respectively. One 5th stage nymph survived for up to 350 days and the females may triplicate their survival rate, what represents an important epidemiological factor. The knowledge about this type of biological characteristic of T. vitticeps may contribute to prevent the domiciliation of this species, what seems to be incipient in some municipal districts, in Brazil.
Collapse
Affiliation(s)
- Carlos José de Carvalho Moreira
- Núcleo de Interação Trypanosoma cruzi-Vetores da Doença de Chagas, Laboratório de Doenças Parasitárias, Departamanto de Medicina Tropical, Instituto Oswaldo Cruz, Rio de Janeiro, RJ, 21045-900, Brasil
| | | |
Collapse
|
14
|
Emmanuelle-Machado P, Koerich LB, Joukoski DDB, Carvalho-Pinto CJ, Grisard EC, Steindel M. Biology of Triatoma klugi Carcavallo, Jurberg, Lent & Galvão 2001 (Heteroptera: Reduviidae) under laboratory conditions: effects of distinct blood sources and susceptibility to Trypanosoma cruzi and Trypanosoma rangeli. Mem Inst Oswaldo Cruz 2002; 97:583-7. [PMID: 12118296 DOI: 10.1590/s0074-02762002000400025] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The life cycle of Triatoma klugi Carcavallo, Jurberg, Lent & Galvão 2001 was compared under laboratory conditions using two groups of the F1 generation obtained from field-collected bugs. Among the 100 nymphs weekly fed on mice (Group A) or chicken (Group B), 77% of Group A and 67% of Group B reached the adult stage, and the mean time from the first nymphal stage to adult was 190.08 +/- 28.31 days and 221.23 +/- 40.50, respectively. The average span in days for each stage per group and the number of blood meals required for each stage were also evaluated. The overall mortality rate was 23% and 33% for Groups A and B, respectively. The mean number of eggs laid per month in a three-month period was of 56.20, 51.70 and 73.20 for Group A, and 64.50, 53.50 and 38.71 for Group B. Despite the blood source, comparative analysis revealed no statistically significant differences in the life cycle of T. klugi under laboratory conditions. Infection rates over 60% were observed for both Trypanosoma cruzi strains tested. Even revealing high infection rates of the hemolymph by T. rangeli strains, T. klugi revealed no salivary gland infections and was not able to transmit the parasite.
Collapse
Affiliation(s)
- Priscilla Emmanuelle-Machado
- Departamento de Microbiologia e Parasitologia, Universidade Federal de Santa Catarina, Florianópolis, SC, 88040-900, Brasil
| | | | | | | | | | | |
Collapse
|
15
|
Gonçalves TC, Rocha DS, Cunha RA. Feeding patterns of Triatoma vitticeps in the State of Rio de Janeiro, Brazil. Rev Saude Publica 2000; 34:348-52. [PMID: 10973153 DOI: 10.1590/s0034-89102000000400006] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
OBJECTIVE Feeding patterns of triatomines have contributed to elucidate its biology. Triatoma vitticeps, naturally infected with T. cruzi, has been found in domiciles. Its behavior and epidemiological patterns were investigated. METHODS One-hundred and twenty two specimens of T. vitticeps were captured from February 1989 to April 1993 in two areas of Triunfo municipality, a subdistrict of Santa Maria Madalena municipal district, State of Rio de Janeiro, Brazil. The insects were dissected and their intestinal contents were removed and tested. It was used antisera from: man, cow, horse, dog, pig, armadillo, opossum, rodent, and bird. RESULTS From the total analyzed, 79 were positive and 43 were negative to the nine antisera tested: armadillo (30.3%) > human and pig (13.1%) > bird and dog (11.5%) > horse (5.7%) > opossum (4.9%) > rodent (4. 1%) > cow (3.3%). Blood meals ranged from 0 to 4 and 6 in the following distribution: 0 = 25.41%; 1 = 45.08%; 2 = 10.66%; 3 = 6. 56%; 4 = 1.64%, and 6 = 0.82%. Nine of the 122 insects captured were not examined, 74 (65.54%) were positive for T. cruzi infection and 39 (34.51%) were negative. CONCLUSIONS These results identified the T. vitticeps as being a sylvatic species and trypanosomiasis as being an enzootic disease. Epidemiological vigilance will be important to provide more information regarding the behavior of the species
Collapse
Affiliation(s)
- T C Gonçalves
- Departamento de Entomologia, Instituto swaldo Cruz, Fiocruz, Rio de Janeiro, RJ, Brasil.
| | | | | |
Collapse
|
16
|
Gonçalves TC, de Oliveira E, Dias LS, Almeida MD, Nogueira WO, Pires FD. An investigation on the ecology of Triatoma vitticeps (Stal, 1859) and its possible role in the transmission of Trypanosoma cruzi, in the locality of Triunfo, Santa Maria Madalena municipal district, state of Rio de Janeiro, Brazil. Mem Inst Oswaldo Cruz 1998; 93:711-7. [PMID: 9921289 DOI: 10.1590/s0074-02761998000600002] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
From January 1989 to April 1995, 465 specimens of Triatoma vitticeps were collected in the locality of Triunfo, 2nd District of Santa Maria Madalena municipal district, State of Rio de Janeiro. The bugs were found indoors by local residents with predominance of adults. The flight activity was high in hot months when the incidence in the domicile also increased. Two hundred and two bugs (111 alive and 91 dead) were examined for Trypanosoma cruzi infection. This was detected in 31 of the dead bugs (34%) and 88 (79%) of the live bugs examined. With a view to investigate the possible vertebrate hosts of the T. cruzi isolates, the blood of 122 mammals was examined through Giemsa-stained smears, hemocultures and xenodiagnosis. T. cruzi was detected in three specimens of Didelphis marsupialis and T. (M.) theileri was detected in one specimen of Bos taurus. The parasites were isolated from triatomine feces, xenoculture and hemoculture. No evidence of human infection was detected in 58 inhabitants examined, as evaluated by indirect imunofluorescence technique using T. cruzi epimastigotes as antigens. These results show that T. vitticeps is still a sylvatic species although nymphs have been found inside the domicile. Thus, an epidemiological vigilance is necessary to know the behaviour of this species following the continuous modifications promoted by the presence of man.
Collapse
Affiliation(s)
- T C Gonçalves
- Núcleo de Morfologia, Anatomia Interna e Ultraestrutura de Artrópodos Vetores/Laboratório de Transmissores de Leishmaniose e Oncocercose, Rio de Janeiro, RJ, Brasil.
| | | | | | | | | | | |
Collapse
|
17
|
Gonçalves TC, Cunha V, de Oliveira E, Jurberg J. [Various aspects of the biology of Triatoma pseudomaculata Corrêa & Espínola, 1964, in laboratory conditions (Hemiptera:Reduviidae:Triatominae)]. Mem Inst Oswaldo Cruz 1997; 92:275-80. [PMID: 9332591 DOI: 10.1590/s0074-02761997000200024] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Observations were made on the evolutive cycle of Triatoma pseudomaculata, held under laboratory conditions, fed weekly on bird (pigeon). Of 60 eggs obtained, only 34 nymphs reached the adult stage in a period of X(S) = 398 +/- 76 days. The following parameters were observed: the time immature stages took to develop from egg to adult emergence; the occurrence of the first meal; the time-lapse between the presenting of the blood-meal and the beginning of feeding; time of feeding; amount of blood ingested; variation of weight 24 hr after the blood-meal and until the next blood-meal; and the defecation pattern. The experiment was carried out for 20 months, held in BOD incubator with the average of temperature and humidity of 28 +/- 1 degrees C and 80 +/- 5% RU, respectively.
Collapse
Affiliation(s)
- T C Gonçalves
- Departamento de Entomologia, Instituto Oswaldo Cruz, Rio de Janeiro, Brasil.
| | | | | | | |
Collapse
|