Space-time clustering of childhood malaria at the household level: a dynamic cohort in a Mali village
<p>Abstract</p> <p>Background</p> <p>Spatial and temporal heterogeneities in the risk of malaria have led the WHO to recommend fine-scale stratification of the epidemiological situation, making it possible to set up actions and clinical or basic researches targeting hig...
| Main Authors: | , , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
BMC
2006-11-01
|
| Series: | BMC Public Health |
| Online Access: | http://www.biomedcentral.com/1471-2458/6/286 |
| _version_ | 1811318102856564736 |
|---|---|
| author | Ouattara Amed Diawara Sory Diallo Mouctar Sagara Issaka Toure Ousmane Ranque Stéphane Dicko Alassane Poudiougou Belco Gaudart Jean Diakite Mahamadou Doumbo Ogobara K |
| author_facet | Ouattara Amed Diawara Sory Diallo Mouctar Sagara Issaka Toure Ousmane Ranque Stéphane Dicko Alassane Poudiougou Belco Gaudart Jean Diakite Mahamadou Doumbo Ogobara K |
| author_sort | Ouattara Amed |
| collection | DOAJ |
| description | <p>Abstract</p> <p>Background</p> <p>Spatial and temporal heterogeneities in the risk of malaria have led the WHO to recommend fine-scale stratification of the epidemiological situation, making it possible to set up actions and clinical or basic researches targeting high-risk zones. Before initiating such studies it is necessary to define local patterns of malaria transmission and infection (in time and in space) in order to facilitate selection of the appropriate study population and the intervention allocation. The aim of this study was to identify, spatially and temporally, high-risk zones of malaria, at the household level (resolution of 1 to 3 m).</p> <p>Methods</p> <p>This study took place in a Malian village with hyperendemic seasonal transmission as part of Mali-Tulane Tropical Medicine Research Center (NIAID/NIH). The study design was a dynamic cohort (22 surveys, from June 1996 to June 2001) on about 1300 children (<12 years) distributed between 173 households localized by GPS. We used the computed parasitological data to analyzed levels of <it>Plasmodium falciparum, P. malariae </it>and <it>P. ovale </it>infection and <it>P. falciparum </it>gametocyte carriage by means of time series and Kulldorff's scan statistic for space-time cluster detection.</p> <p>Results</p> <p>The time series analysis determined that malaria parasitemia (primarily <it>P. falciparum</it>) was persistently present throughout the population with the expected seasonal variability pattern and a downward temporal trend. We identified six high-risk clusters of <it>P. falciparum </it>infection, some of which persisted despite an overall tendency towards a decrease in risk. The first high-risk cluster of <it>P. falciparum </it>infection (rate ratio = 14.161) was detected from September 1996 to October 1996, in the north of the village.</p> <p>Conclusion</p> <p>This study showed that, although infection proportions tended to decrease, high-risk zones persisted in the village particularly near temporal backwaters. Analysis of this heterogeneity at the household scale by GIS methods lead to target preventive actions more accurately on the high-risk zones identified. This mapping of malaria risk makes it possible to orient control programs, treating the high-risk zones identified as a matter of priority, and to improve the planning of intervention trials or research studies on malaria.</p> |
| first_indexed | 2024-04-13T12:21:08Z |
| format | Article |
| id | doaj.art-01673894e35c43b6b54e990f21afb6aa |
| institution | Directory Open Access Journal |
| issn | 1471-2458 |
| language | English |
| last_indexed | 2024-04-13T12:21:08Z |
| publishDate | 2006-11-01 |
| publisher | BMC |
| record_format | Article |
| series | BMC Public Health |
| spelling | doaj.art-01673894e35c43b6b54e990f21afb6aa2022-12-22T02:47:13ZengBMCBMC Public Health1471-24582006-11-016128610.1186/1471-2458-6-286Space-time clustering of childhood malaria at the household level: a dynamic cohort in a Mali villageOuattara AmedDiawara SoryDiallo MouctarSagara IssakaToure OusmaneRanque StéphaneDicko AlassanePoudiougou BelcoGaudart JeanDiakite MahamadouDoumbo Ogobara K<p>Abstract</p> <p>Background</p> <p>Spatial and temporal heterogeneities in the risk of malaria have led the WHO to recommend fine-scale stratification of the epidemiological situation, making it possible to set up actions and clinical or basic researches targeting high-risk zones. Before initiating such studies it is necessary to define local patterns of malaria transmission and infection (in time and in space) in order to facilitate selection of the appropriate study population and the intervention allocation. The aim of this study was to identify, spatially and temporally, high-risk zones of malaria, at the household level (resolution of 1 to 3 m).</p> <p>Methods</p> <p>This study took place in a Malian village with hyperendemic seasonal transmission as part of Mali-Tulane Tropical Medicine Research Center (NIAID/NIH). The study design was a dynamic cohort (22 surveys, from June 1996 to June 2001) on about 1300 children (<12 years) distributed between 173 households localized by GPS. We used the computed parasitological data to analyzed levels of <it>Plasmodium falciparum, P. malariae </it>and <it>P. ovale </it>infection and <it>P. falciparum </it>gametocyte carriage by means of time series and Kulldorff's scan statistic for space-time cluster detection.</p> <p>Results</p> <p>The time series analysis determined that malaria parasitemia (primarily <it>P. falciparum</it>) was persistently present throughout the population with the expected seasonal variability pattern and a downward temporal trend. We identified six high-risk clusters of <it>P. falciparum </it>infection, some of which persisted despite an overall tendency towards a decrease in risk. The first high-risk cluster of <it>P. falciparum </it>infection (rate ratio = 14.161) was detected from September 1996 to October 1996, in the north of the village.</p> <p>Conclusion</p> <p>This study showed that, although infection proportions tended to decrease, high-risk zones persisted in the village particularly near temporal backwaters. Analysis of this heterogeneity at the household scale by GIS methods lead to target preventive actions more accurately on the high-risk zones identified. This mapping of malaria risk makes it possible to orient control programs, treating the high-risk zones identified as a matter of priority, and to improve the planning of intervention trials or research studies on malaria.</p>http://www.biomedcentral.com/1471-2458/6/286 |
| spellingShingle | Ouattara Amed Diawara Sory Diallo Mouctar Sagara Issaka Toure Ousmane Ranque Stéphane Dicko Alassane Poudiougou Belco Gaudart Jean Diakite Mahamadou Doumbo Ogobara K Space-time clustering of childhood malaria at the household level: a dynamic cohort in a Mali village BMC Public Health |
| title | Space-time clustering of childhood malaria at the household level: a dynamic cohort in a Mali village |
| title_full | Space-time clustering of childhood malaria at the household level: a dynamic cohort in a Mali village |
| title_fullStr | Space-time clustering of childhood malaria at the household level: a dynamic cohort in a Mali village |
| title_full_unstemmed | Space-time clustering of childhood malaria at the household level: a dynamic cohort in a Mali village |
| title_short | Space-time clustering of childhood malaria at the household level: a dynamic cohort in a Mali village |
| title_sort | space time clustering of childhood malaria at the household level a dynamic cohort in a mali village |
| url | http://www.biomedcentral.com/1471-2458/6/286 |
| work_keys_str_mv | AT ouattaraamed spacetimeclusteringofchildhoodmalariaatthehouseholdleveladynamiccohortinamalivillage AT diawarasory spacetimeclusteringofchildhoodmalariaatthehouseholdleveladynamiccohortinamalivillage AT diallomouctar spacetimeclusteringofchildhoodmalariaatthehouseholdleveladynamiccohortinamalivillage AT sagaraissaka spacetimeclusteringofchildhoodmalariaatthehouseholdleveladynamiccohortinamalivillage AT toureousmane spacetimeclusteringofchildhoodmalariaatthehouseholdleveladynamiccohortinamalivillage AT ranquestephane spacetimeclusteringofchildhoodmalariaatthehouseholdleveladynamiccohortinamalivillage AT dickoalassane spacetimeclusteringofchildhoodmalariaatthehouseholdleveladynamiccohortinamalivillage AT poudiougoubelco spacetimeclusteringofchildhoodmalariaatthehouseholdleveladynamiccohortinamalivillage AT gaudartjean spacetimeclusteringofchildhoodmalariaatthehouseholdleveladynamiccohortinamalivillage AT diakitemahamadou spacetimeclusteringofchildhoodmalariaatthehouseholdleveladynamiccohortinamalivillage AT doumboogobarak spacetimeclusteringofchildhoodmalariaatthehouseholdleveladynamiccohortinamalivillage |