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Campos M, Alonso DP, Conn JE, Vinetz JM, Emerson KJ, Ribolla PEM. Genetic diversity of Nyssorhynchus (Anopheles) darlingi related to biting behavior in western Amazon. Parasit Vectors 2019; 12:242. [PMID: 31101131 PMCID: PMC6525393 DOI: 10.1186/s13071-019-3498-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 05/09/2019] [Indexed: 01/14/2023] Open
Abstract
Background In the Amazon Basin, Nyssorhynchus (Anopheles) darlingi is the most aggressive and effective malaria vector. In endemic areas, behavioral aspects of anopheline vectors such as host preference, biting time and resting location post blood meal have a key impact on malaria transmission dynamics and vector control interventions. Nyssorhynchus darlingi presents a range of feeding and resting behaviors throughout its broad distribution. Methods To investigate the genetic diversity related to biting behavior, we collected host-seeking Ny. darlingi in two settlement types in Acre, Brazil: Granada (~ 20-year-old, more established, better access by road, few malaria cases) and Remansinho (~ 8-year-old, active logging, poor road access, high numbers malaria cases). Mosquitoes were classified by the location of collection (indoors or outdoors) and time (dusk or dawn). Results Genome-wide SNPs, used to assess the degree of genetic divergence and population structure, identified non-random distributions of individuals in the PCA for both location and time analyses. Although genetic diversity related to behavior was confirmed by non-model-based analyses and FST values, model-based STRUCTURE detected considerable admixture of these populations. Conclusions To our knowledge, this is the first study to detect genetic markers associated with biting behavior in Ny. darlingi. Additional ecological and genomic studies may help to understand the genetic basis of mosquito behavior and address appropriate surveillance and vector control. Electronic supplementary material The online version of this article (10.1186/s13071-019-3498-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Melina Campos
- Biotechnology Institute (IBTEC) & Biosciences Institute at Botucatu (IBB), Sao Paulo State University (UNESP), Sao Paulo, Brazil
| | - Diego Peres Alonso
- Biotechnology Institute (IBTEC) & Biosciences Institute at Botucatu (IBB), Sao Paulo State University (UNESP), Sao Paulo, Brazil
| | - Jan E Conn
- Department of Biomedical Sciences, School of Public Health, University at Albany (State University of New York), Albany, NY, USA.,Wadsworth Center, New York State Department of Health, Albany, NY, USA
| | - Joseph M Vinetz
- Division of Infectious Diseases, Department of Medicine, University of California, San Diego, La Jolla, California, USA.,Laboratorio de Investigación y Desarrollo, Departamento de Ciencias Celulares y Moleculares, Instituto de Medicina Tropical "Alexander von Humboldt", Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Kevin J Emerson
- Biology Department, St. Mary's College of Maryland, St. Mary's City, MD, USA
| | - Paulo Eduardo Martins Ribolla
- Biotechnology Institute (IBTEC) & Biosciences Institute at Botucatu (IBB), Sao Paulo State University (UNESP), Sao Paulo, Brazil.
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Pereira VA, Sánchez-Arcila JC, Vasconcelos MPA, Ferreira AR, de Souza Videira L, Teva A, Perce-da-Silva D, Marques MTQ, de Carvalho LH, Banic DM, Pôrto LCS, Oliveira-Ferreira J. Evaluating seroprevalence to circumsporozoite protein to estimate exposure to three species of Plasmodium in the Brazilian Amazon. Infect Dis Poverty 2018; 7:46. [PMID: 29754588 PMCID: PMC5950184 DOI: 10.1186/s40249-018-0428-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Accepted: 04/19/2018] [Indexed: 11/20/2022] Open
Abstract
Background Brazil has seen a great decline in malaria and the country is moving towards elimination. However, for eventual elimination, the control program needs efficient tools in order to monitor malaria exposure and transmission. In this study, we aimed to evaluate whether seroprevalence to the circumsporozoite protein (CSP) is a good tool for monitoring the exposure to and/or evaluating the burden and distribution of Plasmodium species in the Brazilian Amazon. Methods Cross-sectional surveys were conducted in a rural area of Porto Velho, Rondônia state. Parasite infection was detected by microscopy and polymerase chain reaction. Antibodies to the sporozoite CSP repeats of Plasmodium vivax, P. falciparum, and P. malariae (PvCS, PfCS, and PmCS) were detected using the enzyme-linked immunosorbent assay technique. Human leukocyte antigen (HLA)-DRB1 and DQB1 genes were typed using Luminex® xMAP® technology. Results The prevalence of immunoglobulin G against P. vivax CSP peptide (62%) was higher than P. falciparum (49%) and P. malariae (46%) CSP peptide. Most of the studied individuals had antibodies to at least one of the three peptides (72%), 34% had antibodies to all three peptides and 28% were non-responders. Although the majority of the population was not infected at the time of the survey, 74.3% of parasite-negative individuals had antibodies to at least one of the CSPs. Importantly, among individuals carrying the haplotypes DRB1*04~DQB1*03, there was a significantly higher frequency of PfCS responders, and DRB1*16~DQB1*03 haplotype for PvCS and PfCS responders. In contrast, HLA-DRB1*01 and HLA-DQB1*05 allelic groups were associated with a lack of antibodies to P. vivax and P. falciparum CSP repeats, and the haplotype DRB1*01~DQB1*05 was also associated with non-responders, including non-responders to P. malariae. Conclusions Our results show that in low transmission settings, naturally acquired antibody responses against the CSP repeats of P. vivax, P. falciparum, and P. malariae in a single cross-sectional study may not represent a valuable marker for monitoring recent malaria exposure, especially in an area with a high prevalence of P. vivax. Furthermore, HLA class II molecules play an important role in antibody response and require further study with a larger sample size. It will be of interest to consider HLA analysis when using serosurveillance to monitor malaria exposure among genetically diverse populations. Electronic supplementary material The online version of this article (10.1186/s40249-018-0428-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Virginia Araujo Pereira
- Laboratory of Immunoparasitology, Oswaldo Cruz Institute/Fiocruz, Av. Brasil 4365, Manguinhos, Rio de Janeiro, Brazil
| | - Juan Camilo Sánchez-Arcila
- Laboratory of Immunoparasitology, Oswaldo Cruz Institute/Fiocruz, Av. Brasil 4365, Manguinhos, Rio de Janeiro, Brazil
| | | | - Amanda Ribeiro Ferreira
- Laboratory of Immunoparasitology, Oswaldo Cruz Institute/Fiocruz, Av. Brasil 4365, Manguinhos, Rio de Janeiro, Brazil
| | - Lorene de Souza Videira
- Laboratory of Immunoparasitology, Oswaldo Cruz Institute/Fiocruz, Av. Brasil 4365, Manguinhos, Rio de Janeiro, Brazil
| | - Antonio Teva
- Laboratory of Immunodiagnosis, Departament of Biological Sciences, National School of Public Health/Fiocruz, Rio de Janeiro, Brazil
| | - Daiana Perce-da-Silva
- Laboratory of Clinical Immunology, Oswaldo Cruz Institute/Fiocruz, Rio de Janeiro, Brazil
| | | | - Luzia Helena de Carvalho
- Molecular Biology and Malaria Immunology Research Group, Centro de Pesquisas René Rachou/Fiocruz, Belo Horizonte, Minas Gerais, Brazil
| | - Dalma Maria Banic
- Laboratory of Clinical Immunology, Oswaldo Cruz Institute/Fiocruz, Rio de Janeiro, Brazil
| | | | - Joseli Oliveira-Ferreira
- Laboratory of Immunoparasitology, Oswaldo Cruz Institute/Fiocruz, Av. Brasil 4365, Manguinhos, Rio de Janeiro, Brazil.
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Gil LHS, Rodrigues MDS, de Lima AA, Katsuragawa TH. SEASONAL DISTRIBUTION OF MALARIA VECTORS (DIPTERA: CULICIDAE) IN RURAL LOCALITIES OF PORTO VELHO, RONDÔNIA, BRAZILIAN AMAZON. Rev Inst Med Trop Sao Paulo 2016. [PMID: 26200969 PMCID: PMC4544253 DOI: 10.1590/s0036-46652015000300014] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
We conducted a survey of the malaria vectors in an area where a power line had been
constructed, between the municipalities of Porto Velho and Rio Branco, in the states
of Rondônia and Acre, respectively. The present paper relates to the results of the
survey of Anopheles fauna conducted in the state of Rondônia. Mosquito field
collections were performed in six villages along the federal highway BR 364 in the
municipality of Porto Velho, namely Porto Velho, Jaci Paraná, Mutum Paraná, Vila
Abunã, Vista Alegre do Abunã, and Extrema. Mosquito captures were performed at three
distinct sites in each locality during the months of February, July, and October 2011
using a protected human-landing catch method; outdoor and indoor captures were
conducted simultaneously at each site for six hours. In the six sampled areas, we
captured 2,185 mosquitoes belonging to seven Anopheles species. Of these specimens,
95.1% consisted of Anopheles darlingi, 1.8% An. triannulatus l.s.,
1.7% An. deaneorum, 0.8% An. konderi l.s., 0.4
An. braziliensis, 0.1% An. albitarsis l.s., and
0.1% An. benarrochi. An. darlingi was the only species found in all
localities; the remaining species occurred in sites with specific
characteristics.
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Rios-Velásquez CM, Martins-Campos KM, Simões RC, Izzo T, dos Santos EV, Pessoa FAC, Lima JBP, Monteiro WM, Secundino NFC, Lacerda MVG, Tadei WP, Pimenta PFP. Experimental Plasmodium vivax infection of key Anopheles species from the Brazilian Amazon. Malar J 2013; 12:460. [PMID: 24359307 PMCID: PMC3878095 DOI: 10.1186/1475-2875-12-460] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2013] [Accepted: 12/17/2013] [Indexed: 01/09/2023] Open
Abstract
Background Anopheles darlingi is the major malaria vector in countries located in the Amazon region. Anopheles aquasalis and Anopheles albitarsis s.l. are also proven vectors in this region. Anopheles nuneztovari s.l. and Anopheles triannulatus s.l. were found infected with Plasmodium vivax; however, their status as vectors is not yet well defined. Knowledge of susceptibility of Amazon anopheline populations to Plasmodium infection is necessary to better understand their vector capacity. Laboratory colonization of An. darlingi, the main Amazon vector, has proven to be difficult and presently An. aquasalis is the only available autonomous colony. Methods Larvae of An. darlingi, An. albitarsis s.l., An. nuneztovari s.l. and An. triannulatus s.l. were collected in the field and reared until adult stage. Adults of An. aquasalis were obtained from a well-established colony. Mosquitoes were blood-fed using a membrane-feeding device containing infected blood from malarial patients. The infection of the distinct Anopheles species was evaluated by the impact variance of the following parameters: (a) parasitaemia density; (b) blood serum inactivation of the infective bloodmeal; (c) influence of gametocyte number on infection rates and number of oocysts. The goal of this work was to compare the susceptibility to P. vivax of four field-collected Anopheles species with colonized An. aquasalis. Results All Anopheles species tested were susceptible to P. vivax infection, nevertheless the proportion of infected mosquitoes and the infection intensity measured by oocyst number varied significantly among species. Inactivation of the blood serum prior to mosquito feeding increased infection rates in An. darlingi and An. triannulatus s.l., but was diminished in An. albitarsis s.l. and An. aquasalis. There was a positive correlation between gametocyte density and the infection rate in all tests (Z = −8.37; p < 0.001) but varied among the mosquito species. Anopheles albitarsis s.l., An. aquasalis and An. nuneztovari s.l. had higher infection rates than An. darlingi. Conclusion All field-collected Anopheles species, as well as colonized An. aquasalis are susceptible to experimental P. vivax infections by membrane feeding assays. Anopheles darlingi, An. albitarsis s.l. and An. aquasalis are very susceptible to P. vivax infection. However, colonized An. aquasalis mosquitoes showed the higher infection intensity represented by infection rate and oocyst numbers. This study is the first to characterize experimental development of Plasmodium infections in Amazon Anopheles vectors and also to endorse that P. vivax infection of colonized An. aquasalis is a feasible laboratory model.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | - Paulo F P Pimenta
- Fundação de Medicina Tropical Dr, Heitor Vieira Dourado, Manaus, AM, Brazil.
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Rosero DA, Naranjo-Diaz N, Alvarez N, Cienfuegos AV, Torres C, Luckhart S, Correa MM. Colombian Anopheles triannulatus (Diptera: Culicidae) Naturally Infected with Plasmodium spp. ISRN PARASITOLOGY 2013; 2013:927453. [PMID: 27335865 PMCID: PMC4890920 DOI: 10.5402/2013/927453] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Accepted: 08/13/2013] [Indexed: 11/23/2022]
Abstract
The role of Anopheles triannulatus as a local vector has not yet been defined for malaria-endemic regions of Colombia. Therefore, the aim of this work was to detect An. triannulatus naturally infected with Plasmodium spp., as an approximation to determining its importance as malaria vector in the country. A total of 510 An. triannulatus were collected in six malaria-endemic localities of NW and SE Colombia from January 2009 to March 2011. In the NW, two specimens were naturally infected; one with Plasmodium vivax VK247, collected biting on humans and the other with Plasmodium falciparum, collected resting on cattle. In the SE, two specimens were positive for P. falciparum. Although these results show An. triannulatus naturally infected with Plasmodium, further studies are recommended to demonstrate the epidemiological importance of this species in malaria-endemic regions of Colombia.
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Affiliation(s)
- Doris A Rosero
- Grupo de Microbiología Molecular, Escuela de Microbiología, Universidad de Antioquia, Calle 67 53-108, Lab 5-430, Medellín, Colombia
| | - Nelson Naranjo-Diaz
- Grupo de Microbiología Molecular, Escuela de Microbiología, Universidad de Antioquia, Calle 67 53-108, Lab 5-430, Medellín, Colombia
| | - Natalí Alvarez
- Grupo de Microbiología Molecular, Escuela de Microbiología, Universidad de Antioquia, Calle 67 53-108, Lab 5-430, Medellín, Colombia
| | - Astrid V Cienfuegos
- Grupo de Microbiología Molecular, Escuela de Microbiología, Universidad de Antioquia, Calle 67 53-108, Lab 5-430, Medellín, Colombia
| | - Carolina Torres
- Linea de Entomología Médica, Programa de Estudio y Control de Enfermedades Tropicales (PECET), Universidad de Antioquia, Sede de Investigación Universitaria (SIU), Calle 62 no. 52-59, Lab 632, Medellín, Colombia
| | - Shirley Luckhart
- Department of Medical Microbiology and Immunology, University of California at Davis, Shields Avenue, Tupper Hall, Room 3146, Davis, CA, USA
| | - Margarita M Correa
- Grupo de Microbiología Molecular, Escuela de Microbiología, Universidad de Antioquia, Calle 67 53-108, Lab 5-430, Medellín, Colombia
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Suárez-Mutis MC, Fé NF, Alecrim W, Coura JR. Night and crepuscular mosquitoes and risk of vector-borne diseases in areas of piassaba extraction in the middle Negro River basin, state of Amazonas, Brazil. Mem Inst Oswaldo Cruz 2009; 104:11-7. [DOI: 10.1590/s0074-02762009000100002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2008] [Accepted: 12/05/2008] [Indexed: 11/22/2022] Open
Affiliation(s)
| | | | - Wilson Alecrim
- Fundação de Medicina Tropical do Amazonas; Centro Universitário Nilton Lins
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7
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Souza-Santos R, de Oliveira MVG, Escobar AL, Santos RV, Coimbra CEA. Spatial heterogeneity of malaria in Indian reserves of southwestern Amazonia, Brazil. Int J Health Geogr 2008; 7:55. [PMID: 18980681 PMCID: PMC2588568 DOI: 10.1186/1476-072x-7-55] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2008] [Accepted: 11/03/2008] [Indexed: 11/25/2022] Open
Abstract
Background Malaria constitutes a major cause of morbidity in the Brazilian Amazon where an estimated 6 million people are considered at high risk of transmission. Indigenous peoples in the Amazon are particularly vulnerable to potentially epidemic disease such as malaria; notwithstanding, very little is known about the epidemiology of malaria in Indian reservations of the region. The aim of this paper is to present a spatial analysis of malaria cases over a four-year time period (2003–2006) among indigenous peoples of the Brazilian State of Rondônia, southwestern Amazon, by using passive morbidity data (results from Giemsa-stained thick blood smears) gathered from the National Malaria Epidemiologic Surveillance System databank. Results A total of 4,160 cases of malaria were recorded in 14 Indian reserves in the State of Rondônia between 2003 and 2006. In six reservations no cases of malaria were reported in the period. Overall, P. vivax accounted for 76.18 of malaria cases reported in the indigenous population of Rondônia. The P. vivax/P. falciparum ratio for the period was 3.78. Two reserves accounted for over half of the cases reported for the total indigenous population in the period – Roosevelt and Pacaas Novas – with a total of 1,646 (39.57%) and 1,145 (27.52%) cases, respectively. Kernel mapping of malaria mean Annual Parasite Index – API according to indigenous reserves and environmental zones revealed a heterogeneous pattern of disease distribution, with one clear area of high risk of transmission comprising reservations of west Rondônia along the Guaporé-Madeira River basins, and another high risk area to the east, on the Roosevelt reserve. Conclusion By means of kernel mapping, it was shown that malaria risk varies widely between Indian reserves and environmental zones defined on the basis of predominant ecologic characteristics and land use patterns observed in the southwestern Brazilian Amazon. The geographical approach in this paper helped to determine where the greatest needs lie for more intensively focused malaria control activities in Indian reserves in the region. It also provided a reference to assess the effectiveness of control measures that have been put in place by Brazilian public health authorities.
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Alves FP, Gil LHS, Marrelli MT, Ribolla PEM, Camargo EP, Da Silva LHP. Asymptomatic carriers of Plasmodium spp. as infection source for malaria vector mosquitoes in the Brazilian Amazon. JOURNAL OF MEDICAL ENTOMOLOGY 2005; 42:777-9. [PMID: 16363160 DOI: 10.1093/jmedent/42.5.777] [Citation(s) in RCA: 128] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
We have described the existence of asymptomatic carriers of Plasmodium vivax and Plasmodium falciparum infections in native Amazon populations. Most of them had low parasitemias, detected only by polymerase chain reaction (PCR). Because they remain symptomless and untreated, we wanted to determine whether they could infect Anopheles darlingi Root, the main Brazilian vector, and act as disease reservoirs. Fifteen adult asymptomatic patients (PCR positive only) were selected, and experimental infections of mosquitoes were performed by direct feeding and by a membrane-feeding system. Seventeen adult symptomatic patients with high parasitemias were used as controls. We found an infection rate in An. darlingi of 1.2% for the asymptomatic carriers and 22% for the symptomatic carriers. Although the asymptomatic group infected mosquitoes at a much lower rate, these patients remain infective longer than treated, symptomatic patients. Also, the prevalence of asymptomatic infections is 4 to 5 times higher than symptomatic infections among natives. These results have implications for the malaria control program in Brazil, which focuses essentially on the treatment of symptomatic patients.
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Affiliation(s)
- Fabiana Piovesan Alves
- Centro de Pesquisa em Medicina Tropical, BR-364 Km 4,5, 78910-210, Porto Velho, Rondônia, Brazil
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9
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Lima JBP, Valle D, Peixoto AA. Analysis of reproductive isolation between sibling species anopheles Albitarsis sensu stricto and Anopheles deaneorum, two malaria vectors belonging to the Albitarsis complex (Diptera: Culicidae). JOURNAL OF MEDICAL ENTOMOLOGY 2004; 41:888-893. [PMID: 15535617 DOI: 10.1603/0022-2585-41.5.888] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Complexes of sibling species are common among mosquitoes, and their existence within vector species can have important epidemiological consequences. Anopheles albitarsis sensu stricto and Anopheles deaneorum Rosa-Freitas are two putative vectors of malaria parasites belonging to the Albitarsis species complex (Diptera: Culicidae). Using an induced mating technique, we studied the reproductive isolation between these two closely related species and their reciprocal hybrids. Evidence for hybrid male sterility consistent with Haldane's rule was found. The results indicate that male hybrids show very low insemination rates, probably due to abnormalities in their reproductive organs. In addition, the data show that hybrid males carrying an X chromosome derived from An. deaneorum perform significantly worse than hybrid males carrying an An. albitarsis s.s. X chromosome.
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Affiliation(s)
- José Bento Pereira Lima
- Departments of Entomology and Biochemistry and Molecular Biology, Fundação Oswaldo Cruz, Av. Brasil, 4365, Manguinhos, Rio de Janeiro, RJ 21045-900, Brazil
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10
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Gil LHS, Alves FP, Zieler H, Salcedo JMV, Durlacher RR, Cunha RPA, Tada MS, Camargo LMA, Camargo EP, Pereira-da-Silva LH. Seasonal malaria transmission and variation of anopheline density in two distinct endemic areas in Brazilian Amazonia. JOURNAL OF MEDICAL ENTOMOLOGY 2003; 40:636-641. [PMID: 14596276 DOI: 10.1603/0022-2585-40.5.636] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Studies on seasonal anopheline fauna variation were performed in two distinct settlements in the State of Rondônia, Brazil: one at the Madeira River banks (Portuchuelo) with stable native Amazonian population; the other at an inland lumber-extracting farm (Urupá) in dry land, in which adults are mostly migrants. During a 6-yr period (1994-2000), 8,638 adult anophelines were collected: 2,684 in Urupá and 5,954 in Portuchuelo. Anopheles darlingi represented >95% of total mosquitoes caught. Dissection of 4,424 A. darlingi females yielded a very low sporozoite infection index below 0.1%. Oocysts were found in both localities in approximately 0.1% of dissected mosquitoes. Determination of the hour biting rates disclosed seasonal variations in both localities. However, in Portuchuelo, mosquito density peaked at the acme of the rainy season, whereas at Urupá it peaked in the dry season. The increase in mosquito density and incidence of malaria cases were coincident. The high mosquito densities observed in the riverine settlement of Portochuelo sector B, which permits evaluation in > 10,000 mosquitoes' bites/person/year, could explain, in spite of the low mosquito's infection index, the previously described development of natural immunity in the local population that is not observed in the dry land agroindustrial settlement of Urupá.
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Affiliation(s)
- Luís H Soares Gil
- Centro de Pesquisa em Medicina Tropical, Porto Velho, Rondônia, 78910-210, Brazil
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11
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dos Santos JMM, Maia JDF, Tadei WP, Rodriguez GAD. Isoenzymatic variability among five Anopheles species belonging to the Nyssorhynchus and Anopheles subgenera of the Amazon region, Brazil. Mem Inst Oswaldo Cruz 2003; 98:247-53. [PMID: 12764442 DOI: 10.1590/s0074-02762003000200014] [Citation(s) in RCA: 8] [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
An isoenzymatic comparative analysis of the variability and genetics differentiation among Anopheles species was done in populations of An. (Nys.) intermedius and An. (Ano.) mattogrossensis of the Anopheles subgenus, and of An. darlingi, An. albitarsis and An. triannulatus of the Nyssorhynchus subgenus, with the aim of detecting differences between both subgenera and of estimating the degree of genetic intere specific divergence. Samples from Macap , State of Amap and Janauari Lake, near Manaus, State of Amazonas, were analyzed for eight isoenzymatic loci. Analysis revealed differences in the average number of alleles per locus (1.6-2.3) and heterozygosity (0.060-0.284). However, the proportion of polymorphic loci was the same for An. (Nys.) darlingi, An. (Nys.) triannulatus and An. (Ano.) mattogrossensis (50%), but differed for An. (Nys.) albitarsis (62.5%) and An. (Ano.) intermedius (25%). Only the IDH1 (P > 0.5) locus in all species studied was in Hardy-Weinberg equilibrium. The fixation index demonstrated elevated genetic structuring among species, based on values of Fst = 0.644 and genetic distance (0.344-0.989). Genetic difference was higher between An. (Nys.) triannulatus and An. (Ano.) intermedius (0.989) and smaller between An. (Nys.) albitarsis sensu lato and An. (Nys.) darlingi (0.344). The data show interspecific genetic divergence which differs from the phylogenetic hypothesis based on morphological characters.
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12
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Rodrigues IB, Tadei WP, Dias JM. Larvicidal activity of Bacillus sphaericus 2362 against Anopheles nuneztovari, Anopheles darlingi and Anopheles braziliensis (Diptera, Culicidae). Rev Inst Med Trop Sao Paulo 1999; 41:101-5. [PMID: 10413957 DOI: 10.1590/s0036-46651999000200007] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
In this present study, preliminary data was obtained regarding the mortality rate of the Amazonian anophelines, Anopheles nuneztovari, Anopheles darlingi and Anopheles braziliensis when subjected to treatment with Bacillus sphaericus strain 2362, the WHO standard strain. Initially, experiments were conducted to test the mortality rate of the three species of anopheline larvae. The third larval instar of An. nuneztovari and the second and third larval instars of An. darlingi proved to be the least susceptible. In other experiments, the same three mosquito species were tested with the standard strain 2362, An. nuneztovari was the least susceptible to this insect pathogen, while An. braziliensis was the most susceptible. This latter species showed a difference in the level of LC50 concentration, when compared to the former, of 2.4, 2.5 and 1.8 in readings taken 24, 48 and 72 hours after exposure to the bacillus.
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Affiliation(s)
- I B Rodrigues
- Instituto Nacional de Pesquisas da Amazônia, Manaus, Brazil.
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13
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Forattini OP, Kakitani I, Massad E, Marucci D. Studies on mosquitoes (Diptera:Culicidae) and anthropic environment. 12-host-seeking behaviour of Anopheles albitarsis s.l. in south-eastern Brazil. Rev Saude Publica 1996; 30:299-303. [PMID: 9201890 DOI: 10.1590/s0034-89101996000400002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Results obtained with Anopheles albitarsis s.l. catches mainly performed through human bait at the Ribeira Valley region, SP (Brazil), are reported. Two species of the complex were recognized, namely An. albitarsis s.s. and species B. This latter predominated both in the rice fields and in the dwelling environments. The crepuscular rhythms showed an unimodal sunset pattern with most blood-seeking females caught during dusk. The absence of differences between indoor and outdoor behavior was confirmed for both species of the complex.
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Affiliation(s)
- O P Forattini
- Departamento de Epidemiologia, Faculdade de Saúde Pública, Universidade de São Paulo, Brasil.
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Forattini OP, Kakitani I, Massad E, Marucci D. Studies on mosquitoes (Diptera: Culicidae) and anthropic environment. 7-behaviour of adults Nyssorhynchus anophelines with special reference to Anopheles albitarsis s.l. in south-eastern Brazil. Rev Saude Publica 1995; 29:20-6. [PMID: 8525310 DOI: 10.1590/s0034-89101995000100005] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Results obtained with catches performed at several sites of the Ribeira Valley, SP (Brazil) are reported. Collections with Shannon type traps showed a concentration of An.albitarsis s.l. in the Experimental Farm of Pariquera-Açu County, associated with the development of irrigated rice cultivation. Two species of the complex, named A and B, were recognized. Species B predominated in the samples. Indoor and outdoor crepuscular human bait captures were performed a the domiciliary environment. The two species showed a generally low William's media valve of 0.2, the highest value obtained was 1.6. No differences were found between indoor and outdoor behaviours between the two species of the complex.
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Affiliation(s)
- O P Forattini
- Department of Epidemiology, School of Public Health, University of S. Paulo, Brazil
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15
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Abstract
Over 61,000 anophelines collected between January 1988 and October 1989 in three villages in western Venezuela were assayed by ELISA for Plasmodium vivax circumsporozoite (CS) protein. The six specimens confirmed positive belonged to three species: Anopheles (Nyssorhynchus) nuneztovari Gabaldón, 1940, A. albitarsis Arribalzaga, 1878 sensu lato and A. oswaldoi (Peryassu, 1922). The estimated CS protein rate for all species combined was 0.01% (95% confidence limits 0.004-0.02%). This CS protein rate and the mean number of bites received by the collectors indicated a sporozoite inoculation rate of about 10.5 infective bites per person per year. From this value and the number of human malaria cases reported it was estimated that only 0.32% of bites by CS-positive mosquitoes led to a malaria infection. The CS protein rate is so low that this parameter would not be a practical indicator of the efficacy of control campaigns in this area.
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Affiliation(s)
- Y Rubio-Palis
- Division de Investigaciones, Escuela de Malariologia y Saneamiento Ambiental, Ministerio de Sanidad y Asistencia Social, Maracay, Venezuela
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16
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Abstract
A review is presented of the interrelationships between arthropod vectors, the diseases they transmit and agricultural development. Particular attention is given to the effects of deforestation, livestock development and irrigation on the abundance of vectors and changing patterns of diseases such as malaria, trypanosomiasis, leishmaniasis, Chagas' and some arboviral infections. The question as whether keeping livestock diverts biting away from people and reduces diseases such as malaria--that is zooprophylaxis, or whether the presence of cattle actually increases biting populations is discussed.
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Affiliation(s)
- M W Service
- Liverpool School of Tropical Medicine, Department of Medical Entomology, UK
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