Malaria and its possible control on the island of Príncipe

<p>Abstract</p> <p>Background</p> <p>Malaria can be eradicated from islands. To assess the prospects for eradication of malaria from the island of Príncipe in the Gulf of Guinea, we fitted a mathematical model to age-prevalence curves and thus obtained estimates of the...

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Main Authors: Ferreira Conceição, Gil Vilfrido, Charlwood J Derek, Hagmann Reto, do Rosário Virgíllo, Smith Tom A
Format: Article
Language:English
Published: BMC 2003-06-01
Series:Malaria Journal
Online Access:http://www.malariajournal.com/content/2/1/15
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author Ferreira Conceição
Gil Vilfrido
Charlwood J Derek
Hagmann Reto
do Rosário Virgíllo
Smith Tom A
author_facet Ferreira Conceição
Gil Vilfrido
Charlwood J Derek
Hagmann Reto
do Rosário Virgíllo
Smith Tom A
author_sort Ferreira Conceição
collection DOAJ
description <p>Abstract</p> <p>Background</p> <p>Malaria can be eradicated from islands. To assess the prospects for eradication of malaria from the island of Príncipe in the Gulf of Guinea, we fitted a mathematical model to age-prevalence curves and thus obtained estimates of the vectorial capacity and of the basic reproductive number (<it>R</it><sub>0</sub>) for malaria.</p> <p>Methods</p> <p>A cross-sectional malariological survey was carried out, in mid-1999, in six communities, comprising circa 17% of the total 6,000 population of the island. All houses in these communities were registered and their mode of construction recorded. Thick and thin blood films were prepared from all consenting individuals. Each individual was asked whether they possessed a mosquito net, whether they had slept under a mosquito net the previous night, whether they were allergic to chloroquine, and whether they had visited the main island of São Tomé since the beginning of the year. Outpatient records from March 1999 until the end of December 2000 were also examined and the age and place of residence of diagnosed cases noted.</p> <p>Results</p> <p>203 (19.8%) of the 1,026 individuals examined were found to be infected with <it>Plasmodium falciparum</it>. By fitting the mathematical model of the Garki project to the age-prevalence curve we estimate that the basic reproductive number, <it>R</it><sub>0</sub>, on the island is approximately 1.6. Over a period of one year, a total of 1,792 <it>P. falciparum </it>cases reported to an outpatient facility at the island's hospital. Overall, 54% of the people interviewed slept under mosquito nets and were at reduced risk of infection. Conversely, people living in houses with openings between the top of the wall and the roof had higher risk of infection.</p> <p>Conclusion</p> <p>This high incidence suggests that most of the malaria cases on the island attend the hospital and that treatment of these cases is an important factor reducing the effective rate of transmission. Providing that clinical cases are effectively treated, endemic malaria can probably be eliminated from the island mainly by reducing exposure to the vector with simple measures such as insecticide-treated nets and mosquito-proofing of dwellings. In contrast to traditional malaria eradication strategies, this would avoid the risk of malaria epidemics because the reduction in <it>R</it><sub>0 </sub>should be sustainable.</p>
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spelling doaj.art-ecb92dbd726e48a9b3ceec2b48cd5a682022-12-21T22:48:54ZengBMCMalaria Journal1475-28752003-06-01211510.1186/1475-2875-2-15Malaria and its possible control on the island of PríncipeFerreira ConceiçãoGil VilfridoCharlwood J DerekHagmann Retodo Rosário VirgílloSmith Tom A<p>Abstract</p> <p>Background</p> <p>Malaria can be eradicated from islands. To assess the prospects for eradication of malaria from the island of Príncipe in the Gulf of Guinea, we fitted a mathematical model to age-prevalence curves and thus obtained estimates of the vectorial capacity and of the basic reproductive number (<it>R</it><sub>0</sub>) for malaria.</p> <p>Methods</p> <p>A cross-sectional malariological survey was carried out, in mid-1999, in six communities, comprising circa 17% of the total 6,000 population of the island. All houses in these communities were registered and their mode of construction recorded. Thick and thin blood films were prepared from all consenting individuals. Each individual was asked whether they possessed a mosquito net, whether they had slept under a mosquito net the previous night, whether they were allergic to chloroquine, and whether they had visited the main island of São Tomé since the beginning of the year. Outpatient records from March 1999 until the end of December 2000 were also examined and the age and place of residence of diagnosed cases noted.</p> <p>Results</p> <p>203 (19.8%) of the 1,026 individuals examined were found to be infected with <it>Plasmodium falciparum</it>. By fitting the mathematical model of the Garki project to the age-prevalence curve we estimate that the basic reproductive number, <it>R</it><sub>0</sub>, on the island is approximately 1.6. Over a period of one year, a total of 1,792 <it>P. falciparum </it>cases reported to an outpatient facility at the island's hospital. Overall, 54% of the people interviewed slept under mosquito nets and were at reduced risk of infection. Conversely, people living in houses with openings between the top of the wall and the roof had higher risk of infection.</p> <p>Conclusion</p> <p>This high incidence suggests that most of the malaria cases on the island attend the hospital and that treatment of these cases is an important factor reducing the effective rate of transmission. Providing that clinical cases are effectively treated, endemic malaria can probably be eliminated from the island mainly by reducing exposure to the vector with simple measures such as insecticide-treated nets and mosquito-proofing of dwellings. In contrast to traditional malaria eradication strategies, this would avoid the risk of malaria epidemics because the reduction in <it>R</it><sub>0 </sub>should be sustainable.</p>http://www.malariajournal.com/content/2/1/15
spellingShingle Ferreira Conceição
Gil Vilfrido
Charlwood J Derek
Hagmann Reto
do Rosário Virgíllo
Smith Tom A
Malaria and its possible control on the island of Príncipe
Malaria Journal
title Malaria and its possible control on the island of Príncipe
title_full Malaria and its possible control on the island of Príncipe
title_fullStr Malaria and its possible control on the island of Príncipe
title_full_unstemmed Malaria and its possible control on the island of Príncipe
title_short Malaria and its possible control on the island of Príncipe
title_sort malaria and its possible control on the island of principe
url http://www.malariajournal.com/content/2/1/15
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AT hagmannreto malariaanditspossiblecontrolontheislandofprincipe
AT dorosariovirgillo malariaanditspossiblecontrolontheislandofprincipe
AT smithtoma malariaanditspossiblecontrolontheislandofprincipe