Vectorial capacities for malaria in eastern Amazonian Brazil depend on village, vector species, season, and parasite species
Abstract Background The vector species in the Amazon River Basin are regionally and locally diverse, which makes it imperative to understand and compare their roles in malaria transmission to help select appropriate methods of intervention and evaluation. The major aim of this study was to measure t...
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| Format: | Article |
| Language: | English |
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BMC
2022-08-01
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| Series: | Malaria Journal |
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| Online Access: | https://doi.org/10.1186/s12936-022-04255-x |
| _version_ | 1828434696257667072 |
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| author | Robert H. Zimmerman Allan K. R. Galardo L Philip Lounibos Clicia Galardo A. Kadir Bahar Edzard van Santen |
| author_facet | Robert H. Zimmerman Allan K. R. Galardo L Philip Lounibos Clicia Galardo A. Kadir Bahar Edzard van Santen |
| author_sort | Robert H. Zimmerman |
| collection | DOAJ |
| description | Abstract Background The vector species in the Amazon River Basin are regionally and locally diverse, which makes it imperative to understand and compare their roles in malaria transmission to help select appropriate methods of intervention and evaluation. The major aim of this study was to measure the vectorial capacity of five Anopheles species in three neighbouring villages, for two Plasmodium parasite species affecting humans. Methods From 32 consecutive months of sampling in three villages, 1.5–7.0 km apart, on the Matapi River, Amapá State, Brazil, vectorial capacities (C) were estimated as time series for An. darlingi, An. marajoara, An. nuneztovari, An. triannulatus, and An. intermedius. Monthly parity measurements for each vector species were used to estimate daily survivorship and compared to estimates of survivorship from mark-release-recapture experiments. Gonotrophic cycle lengths were estimated through a time-series analysis of parity data, and durations of sporogony at study site temperatures for the two malaria parasite species were estimated from previous literature. Results The absolute abundances of five vector species were strongly tracked by the spatial variation in C among villages. Temporally, C varied between wet and dry seasons, with An. darlingi, An. marajoara and An. triannulatus exhibiting higher C in the dry season from August to December, and An. nuneztovari its highest C early in the rainy season in January and February. Anopheles intermedius exhibited higher C in the rainy season from April to June than in the dry season. Significant differences in overall survival for each independent variable, and a significant difference in C between wet and dry seasons, among villages, and among vector species for both Plasmodium falciparum and Plasmodium vivax. A generalized linear mixed model (GLMM) analysis by village showed significant effects of vector species on C in only one village, but significant effects of parasite species in all three. Although the GLMM analysis detected no significant parasite x vector species interaction effects on C, effects on C of spline regressions of C dynamics x vector species interactions were significant in all villages. Conclusions These detailed analyses of entomological and parasitological variables revealed hidden complexities of malaria epidemiology at local scales in neighbouring riverine villages of the Amazon Region. |
| first_indexed | 2024-12-10T18:53:58Z |
| format | Article |
| id | doaj.art-f11d2ce2269b4e988cc944d94ce5f9e0 |
| institution | Directory Open Access Journal |
| issn | 1475-2875 |
| language | English |
| last_indexed | 2024-12-10T18:53:58Z |
| publishDate | 2022-08-01 |
| publisher | BMC |
| record_format | Article |
| series | Malaria Journal |
| spelling | doaj.art-f11d2ce2269b4e988cc944d94ce5f9e02022-12-22T01:37:14ZengBMCMalaria Journal1475-28752022-08-0121111710.1186/s12936-022-04255-xVectorial capacities for malaria in eastern Amazonian Brazil depend on village, vector species, season, and parasite speciesRobert H. Zimmerman0Allan K. R. Galardo1L Philip Lounibos2Clicia Galardo3A. Kadir Bahar4Edzard van Santen5Florida Medical Entomology Laboratory, University of Florida/IFASLaboratório de Entomologia Médica, Instituto de Pesquisas Científicas E Tecnológicas Do Estado de Amapá-IEPAFlorida Medical Entomology Laboratory, University of Florida/IFASLaboratório de Entomologia Médica, Instituto de Pesquisas Científicas E Tecnológicas Do Estado de Amapá-IEPADepartment of Educational PsychologyAgronomy Department and Statistical Consulting Unit, University of Florida/IFASAbstract Background The vector species in the Amazon River Basin are regionally and locally diverse, which makes it imperative to understand and compare their roles in malaria transmission to help select appropriate methods of intervention and evaluation. The major aim of this study was to measure the vectorial capacity of five Anopheles species in three neighbouring villages, for two Plasmodium parasite species affecting humans. Methods From 32 consecutive months of sampling in three villages, 1.5–7.0 km apart, on the Matapi River, Amapá State, Brazil, vectorial capacities (C) were estimated as time series for An. darlingi, An. marajoara, An. nuneztovari, An. triannulatus, and An. intermedius. Monthly parity measurements for each vector species were used to estimate daily survivorship and compared to estimates of survivorship from mark-release-recapture experiments. Gonotrophic cycle lengths were estimated through a time-series analysis of parity data, and durations of sporogony at study site temperatures for the two malaria parasite species were estimated from previous literature. Results The absolute abundances of five vector species were strongly tracked by the spatial variation in C among villages. Temporally, C varied between wet and dry seasons, with An. darlingi, An. marajoara and An. triannulatus exhibiting higher C in the dry season from August to December, and An. nuneztovari its highest C early in the rainy season in January and February. Anopheles intermedius exhibited higher C in the rainy season from April to June than in the dry season. Significant differences in overall survival for each independent variable, and a significant difference in C between wet and dry seasons, among villages, and among vector species for both Plasmodium falciparum and Plasmodium vivax. A generalized linear mixed model (GLMM) analysis by village showed significant effects of vector species on C in only one village, but significant effects of parasite species in all three. Although the GLMM analysis detected no significant parasite x vector species interaction effects on C, effects on C of spline regressions of C dynamics x vector species interactions were significant in all villages. Conclusions These detailed analyses of entomological and parasitological variables revealed hidden complexities of malaria epidemiology at local scales in neighbouring riverine villages of the Amazon Region.https://doi.org/10.1186/s12936-022-04255-xAnophelesVectorial capacityMalariaAmazon |
| spellingShingle | Robert H. Zimmerman Allan K. R. Galardo L Philip Lounibos Clicia Galardo A. Kadir Bahar Edzard van Santen Vectorial capacities for malaria in eastern Amazonian Brazil depend on village, vector species, season, and parasite species Malaria Journal Anopheles Vectorial capacity Malaria Amazon |
| title | Vectorial capacities for malaria in eastern Amazonian Brazil depend on village, vector species, season, and parasite species |
| title_full | Vectorial capacities for malaria in eastern Amazonian Brazil depend on village, vector species, season, and parasite species |
| title_fullStr | Vectorial capacities for malaria in eastern Amazonian Brazil depend on village, vector species, season, and parasite species |
| title_full_unstemmed | Vectorial capacities for malaria in eastern Amazonian Brazil depend on village, vector species, season, and parasite species |
| title_short | Vectorial capacities for malaria in eastern Amazonian Brazil depend on village, vector species, season, and parasite species |
| title_sort | vectorial capacities for malaria in eastern amazonian brazil depend on village vector species season and parasite species |
| topic | Anopheles Vectorial capacity Malaria Amazon |
| url | https://doi.org/10.1186/s12936-022-04255-x |
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