Cargando…

Reassessment of asymptomatic carriers of Plasmodium spp. in an endemic area with a very low incidence of malaria in extra-Amazonian Brazil

BACKGROUND: Regions with residual transmission are potential obstacles to the elimination of malaria. It is, therefore, essential to understand the factors associated with the maintenance of endemic malaria in these areas. The objective was to investigate whether the status of asymptomatic carriers...

Descripción completa

Detalles Bibliográficos
Autores principales: de Alencar, Filomena E. C., Malafronte, Rosely dos Santos, Cerutti, Crispim, Natal Fernandes, Lícia, Buery, Julyana Cerqueira, Fux, Blima, Rezende, Helder Ricas, Miranda, Angelica Espinosa
Formato: Online Artículo Texto
Lenguaje:English
Publicado: BioMed Central 2017
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5679383/
https://www.ncbi.nlm.nih.gov/pubmed/29121963
http://dx.doi.org/10.1186/s12936-017-2103-6
_version_ 1783277578465837056
author de Alencar, Filomena E. C.
Malafronte, Rosely dos Santos
Cerutti, Crispim
Natal Fernandes, Lícia
Buery, Julyana Cerqueira
Fux, Blima
Rezende, Helder Ricas
Miranda, Angelica Espinosa
author_facet de Alencar, Filomena E. C.
Malafronte, Rosely dos Santos
Cerutti, Crispim
Natal Fernandes, Lícia
Buery, Julyana Cerqueira
Fux, Blima
Rezende, Helder Ricas
Miranda, Angelica Espinosa
author_sort de Alencar, Filomena E. C.
collection PubMed
description BACKGROUND: Regions with residual transmission are potential obstacles to the elimination of malaria. It is, therefore, essential to understand the factors associated with the maintenance of endemic malaria in these areas. The objective was to investigate whether the status of asymptomatic carriers of Plasmodium spp. DNA is maintained in the long term in an extra-Amazonian region of Brazil with low incidence, residual malaria transmission. METHODS: Asymptomatic carriers of Plasmodium DNA detected in a survey carried out between 2001 and 2004 were reassessed between 2010 and 2011 using questionnaires, PCR and thick and thin blood smear tests three times at 3-month intervals. RESULTS: Of the 48 carriers detected between 2001 and 2004, 37 were located. Of these, only two had positive PCR results and, as in the first survey, Plasmodium malariae DNA was detected. CONCLUSION: The findings suggest that untreated dwellers from this extra-Amazonian region, who initially harbour malaria parasites, may become negative without ever developing apparent symptoms of the disease. Although the possibility of re-infection cannot be ruled out, the finding of two individuals harbouring P. malariae, both in the first and in the second survey, may be compatible with a long-term carrier state for this parasite. Since most clinical cases of malaria in the region are a consequence of infection by Plasmodium vivax, the epidemiological impact of such long-term carriage would be limited.
format Online
Article
Text
id pubmed-5679383
institution National Center for Biotechnology Information
language English
publishDate 2017
publisher BioMed Central
record_format MEDLINE/PubMed
spelling pubmed-56793832017-11-17 Reassessment of asymptomatic carriers of Plasmodium spp. in an endemic area with a very low incidence of malaria in extra-Amazonian Brazil de Alencar, Filomena E. C. Malafronte, Rosely dos Santos Cerutti, Crispim Natal Fernandes, Lícia Buery, Julyana Cerqueira Fux, Blima Rezende, Helder Ricas Miranda, Angelica Espinosa Malar J Research BACKGROUND: Regions with residual transmission are potential obstacles to the elimination of malaria. It is, therefore, essential to understand the factors associated with the maintenance of endemic malaria in these areas. The objective was to investigate whether the status of asymptomatic carriers of Plasmodium spp. DNA is maintained in the long term in an extra-Amazonian region of Brazil with low incidence, residual malaria transmission. METHODS: Asymptomatic carriers of Plasmodium DNA detected in a survey carried out between 2001 and 2004 were reassessed between 2010 and 2011 using questionnaires, PCR and thick and thin blood smear tests three times at 3-month intervals. RESULTS: Of the 48 carriers detected between 2001 and 2004, 37 were located. Of these, only two had positive PCR results and, as in the first survey, Plasmodium malariae DNA was detected. CONCLUSION: The findings suggest that untreated dwellers from this extra-Amazonian region, who initially harbour malaria parasites, may become negative without ever developing apparent symptoms of the disease. Although the possibility of re-infection cannot be ruled out, the finding of two individuals harbouring P. malariae, both in the first and in the second survey, may be compatible with a long-term carrier state for this parasite. Since most clinical cases of malaria in the region are a consequence of infection by Plasmodium vivax, the epidemiological impact of such long-term carriage would be limited. BioMed Central 2017-11-09 /pmc/articles/PMC5679383/ /pubmed/29121963 http://dx.doi.org/10.1186/s12936-017-2103-6 Text en © The Author(s) 2017 Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
spellingShingle Research
de Alencar, Filomena E. C.
Malafronte, Rosely dos Santos
Cerutti, Crispim
Natal Fernandes, Lícia
Buery, Julyana Cerqueira
Fux, Blima
Rezende, Helder Ricas
Miranda, Angelica Espinosa
Reassessment of asymptomatic carriers of Plasmodium spp. in an endemic area with a very low incidence of malaria in extra-Amazonian Brazil
title Reassessment of asymptomatic carriers of Plasmodium spp. in an endemic area with a very low incidence of malaria in extra-Amazonian Brazil
title_full Reassessment of asymptomatic carriers of Plasmodium spp. in an endemic area with a very low incidence of malaria in extra-Amazonian Brazil
title_fullStr Reassessment of asymptomatic carriers of Plasmodium spp. in an endemic area with a very low incidence of malaria in extra-Amazonian Brazil
title_full_unstemmed Reassessment of asymptomatic carriers of Plasmodium spp. in an endemic area with a very low incidence of malaria in extra-Amazonian Brazil
title_short Reassessment of asymptomatic carriers of Plasmodium spp. in an endemic area with a very low incidence of malaria in extra-Amazonian Brazil
title_sort reassessment of asymptomatic carriers of plasmodium spp. in an endemic area with a very low incidence of malaria in extra-amazonian brazil
topic Research
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5679383/
https://www.ncbi.nlm.nih.gov/pubmed/29121963
http://dx.doi.org/10.1186/s12936-017-2103-6
work_keys_str_mv AT dealencarfilomenaec reassessmentofasymptomaticcarriersofplasmodiumsppinanendemicareawithaverylowincidenceofmalariainextraamazonianbrazil
AT malafronteroselydossantos reassessmentofasymptomaticcarriersofplasmodiumsppinanendemicareawithaverylowincidenceofmalariainextraamazonianbrazil
AT cerutticrispim reassessmentofasymptomaticcarriersofplasmodiumsppinanendemicareawithaverylowincidenceofmalariainextraamazonianbrazil
AT natalfernandeslicia reassessmentofasymptomaticcarriersofplasmodiumsppinanendemicareawithaverylowincidenceofmalariainextraamazonianbrazil
AT bueryjulyanacerqueira reassessmentofasymptomaticcarriersofplasmodiumsppinanendemicareawithaverylowincidenceofmalariainextraamazonianbrazil
AT fuxblima reassessmentofasymptomaticcarriersofplasmodiumsppinanendemicareawithaverylowincidenceofmalariainextraamazonianbrazil
AT rezendehelderricas reassessmentofasymptomaticcarriersofplasmodiumsppinanendemicareawithaverylowincidenceofmalariainextraamazonianbrazil
AT mirandaangelicaespinosa reassessmentofasymptomaticcarriersofplasmodiumsppinanendemicareawithaverylowincidenceofmalariainextraamazonianbrazil