Leptospirosis in American Samoa--estimating and mapping risk using environmental data.
BACKGROUND: The recent emergence of leptospirosis has been linked to many environmental drivers of disease transmission. Accurate epidemiological data are lacking because of under-diagnosis, poor laboratory capacity, and inadequate surveillance. Predictive risk maps have been produced for many disea...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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Public Library of Science (PLoS)
2012-01-01
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| Series: | PLoS Neglected Tropical Diseases |
| Online Access: | http://europepmc.org/articles/PMC3362644?pdf=render |
| _version_ | 1818565358683947008 |
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| author | Colleen L Lau Colleen L Lau Archie C A Clements Chris Skelly Annette J Dobson Lee D Smythe Philip Weinstein |
| author_facet | Colleen L Lau Colleen L Lau Archie C A Clements Chris Skelly Annette J Dobson Lee D Smythe Philip Weinstein |
| author_sort | Colleen L Lau |
| collection | DOAJ |
| description | BACKGROUND: The recent emergence of leptospirosis has been linked to many environmental drivers of disease transmission. Accurate epidemiological data are lacking because of under-diagnosis, poor laboratory capacity, and inadequate surveillance. Predictive risk maps have been produced for many diseases to identify high-risk areas for infection and guide allocation of public health resources, and are particularly useful where disease surveillance is poor. To date, no predictive risk maps have been produced for leptospirosis. The objectives of this study were to estimate leptospirosis seroprevalence at geographic locations based on environmental factors, produce a predictive disease risk map for American Samoa, and assess the accuracy of the maps in predicting infection risk. METHODOLOGY AND PRINCIPAL FINDINGS: Data on seroprevalence and risk factors were obtained from a recent study of leptospirosis in American Samoa. Data on environmental variables were obtained from local sources, and included rainfall, altitude, vegetation, soil type, and location of backyard piggeries. Multivariable logistic regression was performed to investigate associations between seropositivity and risk factors. Using the multivariable models, seroprevalence at geographic locations was predicted based on environmental variables. Goodness of fit of models was measured using area under the curve of the receiver operating characteristic, and the percentage of cases correctly classified as seropositive. Environmental predictors of seroprevalence included living below median altitude of a village, in agricultural areas, on clay soil, and higher density of piggeries above the house. Models had acceptable goodness of fit, and correctly classified ∼84% of cases. CONCLUSIONS AND SIGNIFICANCE: Environmental variables could be used to identify high-risk areas for leptospirosis. Environmental monitoring could potentially be a valuable strategy for leptospirosis control, and allow us to move from disease surveillance to environmental health hazard surveillance as a more cost-effective tool for directing public health interventions. |
| first_indexed | 2024-12-14T01:40:12Z |
| format | Article |
| id | doaj.art-745d0728f2f94899abe86441cae358b8 |
| institution | Directory Open Access Journal |
| issn | 1935-2735 |
| language | English |
| last_indexed | 2024-12-14T01:40:12Z |
| publishDate | 2012-01-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS Neglected Tropical Diseases |
| spelling | doaj.art-745d0728f2f94899abe86441cae358b82022-12-21T23:21:46ZengPublic Library of Science (PLoS)PLoS Neglected Tropical Diseases1935-27352012-01-0165e166910.1371/journal.pntd.0001669Leptospirosis in American Samoa--estimating and mapping risk using environmental data.Colleen L LauColleen L LauArchie C A ClementsChris SkellyAnnette J DobsonLee D SmythePhilip WeinsteinBACKGROUND: The recent emergence of leptospirosis has been linked to many environmental drivers of disease transmission. Accurate epidemiological data are lacking because of under-diagnosis, poor laboratory capacity, and inadequate surveillance. Predictive risk maps have been produced for many diseases to identify high-risk areas for infection and guide allocation of public health resources, and are particularly useful where disease surveillance is poor. To date, no predictive risk maps have been produced for leptospirosis. The objectives of this study were to estimate leptospirosis seroprevalence at geographic locations based on environmental factors, produce a predictive disease risk map for American Samoa, and assess the accuracy of the maps in predicting infection risk. METHODOLOGY AND PRINCIPAL FINDINGS: Data on seroprevalence and risk factors were obtained from a recent study of leptospirosis in American Samoa. Data on environmental variables were obtained from local sources, and included rainfall, altitude, vegetation, soil type, and location of backyard piggeries. Multivariable logistic regression was performed to investigate associations between seropositivity and risk factors. Using the multivariable models, seroprevalence at geographic locations was predicted based on environmental variables. Goodness of fit of models was measured using area under the curve of the receiver operating characteristic, and the percentage of cases correctly classified as seropositive. Environmental predictors of seroprevalence included living below median altitude of a village, in agricultural areas, on clay soil, and higher density of piggeries above the house. Models had acceptable goodness of fit, and correctly classified ∼84% of cases. CONCLUSIONS AND SIGNIFICANCE: Environmental variables could be used to identify high-risk areas for leptospirosis. Environmental monitoring could potentially be a valuable strategy for leptospirosis control, and allow us to move from disease surveillance to environmental health hazard surveillance as a more cost-effective tool for directing public health interventions.http://europepmc.org/articles/PMC3362644?pdf=render |
| spellingShingle | Colleen L Lau Colleen L Lau Archie C A Clements Chris Skelly Annette J Dobson Lee D Smythe Philip Weinstein Leptospirosis in American Samoa--estimating and mapping risk using environmental data. PLoS Neglected Tropical Diseases |
| title | Leptospirosis in American Samoa--estimating and mapping risk using environmental data. |
| title_full | Leptospirosis in American Samoa--estimating and mapping risk using environmental data. |
| title_fullStr | Leptospirosis in American Samoa--estimating and mapping risk using environmental data. |
| title_full_unstemmed | Leptospirosis in American Samoa--estimating and mapping risk using environmental data. |
| title_short | Leptospirosis in American Samoa--estimating and mapping risk using environmental data. |
| title_sort | leptospirosis in american samoa estimating and mapping risk using environmental data |
| url | http://europepmc.org/articles/PMC3362644?pdf=render |
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