Hostname: page-component-8448b6f56d-dnltx Total loading time: 0 Render date: 2024-04-16T20:43:10.028Z Has data issue: false hasContentIssue false

Spatial risk prediction and mapping of Schistosoma mansoni infections among schoolchildren living in western Côte d'Ivoire

Published online by Cambridge University Press:  24 March 2005

G. RASO
Affiliation:
Department of Public Health and Epidemiology, Swiss Tropical Institute, P.O. Box, CH-4002 Basel, Switzerland Centre Suisse de Recherches Scientifiques, 01 BP 1303, Abidjan 01, Côte d'Ivoire
B. MATTHYS
Affiliation:
Department of Public Health and Epidemiology, Swiss Tropical Institute, P.O. Box, CH-4002 Basel, Switzerland Centre Suisse de Recherches Scientifiques, 01 BP 1303, Abidjan 01, Côte d'Ivoire
E. K. N'GORAN
Affiliation:
Centre Suisse de Recherches Scientifiques, 01 BP 1303, Abidjan 01, Côte d'Ivoire UFR Biosciences, Université d'Abidjan-Cocody, 22 BP 770, Abidjan 22, Côte d'Ivoire
M. TANNER
Affiliation:
Department of Public Health and Epidemiology, Swiss Tropical Institute, P.O. Box, CH-4002 Basel, Switzerland
P. VOUNATSOU
Affiliation:
Department of Public Health and Epidemiology, Swiss Tropical Institute, P.O. Box, CH-4002 Basel, Switzerland
J. UTZINGER
Affiliation:
Department of Public Health and Epidemiology, Swiss Tropical Institute, P.O. Box, CH-4002 Basel, Switzerland

Abstract

The objectives of this study were (1) to examine risk factors for Schistosoma mansoni infection among schoolchildren living in western Côte d'Ivoire, and (2) to carry forward spatial risk prediction and mapping at non-sampled locations. First, demographic and socio-economic data were obtained from 3818 children, aged 6–16 years, from 55 schools. Second, a single stool sample was examined from each child by the Kato-Katz technique to assess infection status of S. mansoni and its intensity. Third, remotely sensed environmental data were derived from satellite imagery and digitized ground maps. With these databases a comprehensive geographical information system was established. Bayesian variogram models were applied for spatial risk modelling and prediction. The infection prevalence of S. mansoni was 38·9%, ranging from 0% to 89·3% among schools. Results showed that age, sex, the richest wealth quintile, elevation and rainfall explained the geographical variation of the school prevalences of S. mansoni infection. The goodness of fit of different spatial models revealed that age, sex and socio-economic status had a stronger influence on infection prevalence than environmental covariates. The generated risk map can be used by decision-makers for the design and implementation of schistosomiasis control in this setting. If successfully validated elsewhere, this approach can guide control programmes quite generally.

Type
Research Article
Copyright
© 2005 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

APPLETON, C. C. ( 1978). Review of literature on abiotic factors influencing the distribution and life-cycles of bilharziasis intermediate host snails. Malacological Review 11, 125.Google Scholar
ARMSTRONG SCHELLENBERG, J., VICTORA, C. G., MUSHI, A., DE SAVIGNY, D., SCHELLENBERG, D., MSHINDA, H. & BRYCE, J. ( 2003). Inequities among the very poor: health care for children in rural southern Tanzania. Lancet 361, 561566.CrossRefGoogle Scholar
BAVIA, M. E., MALONE, J. B., HALE, L., DANTAS, A., MARRONI, L. & REIS, R. ( 2001). Use of thermal and vegetation index data from earth observing satellites to evaluate the risk of schistosomiasis in Bahia, Brazil. Acta Tropica 79, 7985.CrossRefGoogle Scholar
BERHE, N., MEDHIN, G., ERKO, B., SMITH, T., GEDAMU, S., BEREDED, D., MOORE, R., HABTE, E., REDDA, A., GEBRE-MICHAEL, T. & GUNDERSEN, S. G. ( 2004). Variations in helminth faecal egg counts in Kato-Katz thick smears and their implications in assessing infection status with Schistosoma mansoni. Acta Tropica 92, 205212.CrossRefGoogle Scholar
BETHONY, J., WILLIAMS, J. T., BROOKER, S., GAZZINELLI, A., GAZZINELLI, M. F., LO VERDE, P. T., CORREA-OLIVEIRA, R. & KLOOS, H. ( 2004). Exposure to Schistosoma mansoni infection in a rural area in Brazil. Part III: Household aggregation of water-contact behaviour. Tropical Medicine and International Health 9, 381389.Google Scholar
BETHONY, J., WILLIAMS, J. T., KLOOS, H., BLANGERO, J., ALVES-FRAGA, L., BUCK, G., MICHALEK, A., WILLIAMS-BLANGERO, S., LO VERDE, P. T., CORREA-OLIVEIRA, R. & GAZZINELLI, A. ( 2001). Exposure to Schistosoma mansoni infection in a rural area in Brazil. II: Household risk factors. Tropical Medicine and International Health 6, 136145.Google Scholar
BOOTH, M., VOUNATSOU, P., N'GORAN, E. K., TANNER, M. & UTZINGER, J. ( 2003). The influence of sampling effort and the performance of the Kato-Katz technique in diagnosing Schistosoma mansoni and hookworm co-infections in rural Côte d'Ivoire. Parasitology 127, 525531.CrossRefGoogle Scholar
BROOKER, S. ( 2002). Schistosomes, snails and satellites. Acta Tropica 82, 207214.CrossRefGoogle Scholar
BROOKER, S., HAY, S. I. & BUNDY, D. A. P. ( 2002 a). Tools from ecology: useful for evaluating infection risk models? Trends in Parasitology 18, 7074.Google Scholar
BROOKER, S., HAY, S. I., ISSAE, W., HALL, A., KIHAMIA, C. M., LWAMBO, N. J., WINT, W., ROGERS, D. J. & BUNDY, D. A. P. ( 2001). Predicting the distribution of urinary schistosomiasis in Tanzania using satellite sensor data. Tropical Medicine and International Health 6, 9981007.CrossRefGoogle Scholar
BROOKER, S., HAY, S. I., TCHUEM TCHUENTÉ, L. A. & RATARD, R. ( 2002 b). Using NOAA-AVHRR data to model human helminth distributions on planning disease control in Cameroon, West Africa. Photogrammetric Engineering and Remote Sensing 68, 175179.Google Scholar
BROOKER, S. & MICHAEL, E. ( 2000). The potential of geographical information systems and remote sensing in the epidemiology and control of human helminth infections. Advances in Parasitology 47, 245288.CrossRefGoogle Scholar
CHITSULO, L., ENGELS, D., MONTRESOR, A. & SAVIOLI, L. ( 2000). The global status of schistosomiasis and its control. Acta Tropica 77, 4151.CrossRefGoogle Scholar
CRESSIE, N. A. C. ( 1993). Statistics for Spatial Data. Wiley, New York.
CURRAN, P. J., ATKINSON, P. M., FOODY, G. M. & MILTON, E. J. ( 2000). Linking remote sensing, land cover and disease. Advances in Parasitology 47, 3780.CrossRefGoogle Scholar
DIGGLE, P. J., TAWN, J. A. & MOYEED, R. A. ( 1998). Model-based geostatistics. Applied Statistics 47, 299350.CrossRefGoogle Scholar
DOUMENGE, J. P., MOTT, K. E., CHEUNG, C., VILLENAVE, D., CHAPUIS, O., PERRIN, M. F. & REAUD-THOMAS, G. ( 1987). Atlas of the Global Distribution of Schistosomiasis. CEGET/CNRS – Word Health Organization, Talence/Geneva.
ENGELS, D., SINZINKAYO, E. & GRYSEELS, B. ( 1996). Day-to-day egg count fluctuation in Schistosoma mansoni infection and its operational implications. American Journal of Tropical Medicine and Hygiene 54, 319324.CrossRefGoogle Scholar
FILMER, D. & PRITCHETT, L. H. ( 2001). Estimating wealth effects without expenditure data – or tears: an application to educational enrollments in states of India. Demography 38, 115132.Google Scholar
GAZZINELLI, A., BETHONY, J., FRAGA, L. A., LO VERDE, P. T., CORREA-OLIVEIRA, R. & KLOOS, H. ( 2001). Exposure to Schistosoma mansoni infection in a rural area of Brazil. I: Water contact. Tropical Medicine and International Health 6, 126135.Google Scholar
GELFAND, A. E., RAVISHANKER, N. & ECKER, M. ( 1999). Modeling and inference for point-referenced binary spatial data. In Generalized Linear Models ( ed. Dey, D., Ghosh, S. & Mallick, B.), pp. 373386. Marcel Dekker Inc., New York.
GELFAND, A. E. & SMITH, A. F. M. ( 1990). Sampling-based approaches to calculating marginal densities. Journal of the American Statistical Association 85, 398409.CrossRefGoogle Scholar
GENNER, M. J. & MICHEL, E. ( 2003). Fine-scale habitat associations of soft-sediment gastropods at Cape Maclear, Lake Malawi. Journal of Molluscan Studies 69, 325328.CrossRefGoogle Scholar
GREER, G. J., MIMPFOUNDI, R., MALEK, E. A., JOKY, A., NGONSEU, E. & RATARD, R. C. ( 1990). Human schistosomiasis in Cameroon. II. Distribution of the snail hosts. American Journal of Tropical Medicine and Hygiene 42, 573580.CrossRefGoogle Scholar
GRYSEELS, B. ( 1991). The epidemiology of schistosomiasis in Burundi and its consequences for control. Transactions of the Royal Society of Tropical Medicine and Hygiene 85, 626633.CrossRefGoogle Scholar
HAY, S. I. ( 2000). An overview of remote sensing and geodesy for epidemiology and public health application. Advances in Parasitology 47, 135.CrossRefGoogle Scholar
HUSTING, E. L. ( 1983). Human water contact activities related to the transmission of bilharziasis (schistosomiasis). Journal of Tropical Medicine and Hygiene 86, 2335.Google Scholar
KATZ, N., CHAVES, A. & PELLEGRINO, J. ( 1972). A simple device for quantitative stool thick-smear technique in schistosomiasis mansoni. Revista do Instituto Medicina Tropical São Paulo 14, 397400.Google Scholar
KEISER, J., N'GORAN, E. K., TRAORÉ, M., LOHOURIGNON, K. L., SINGER, B. H., LENGELER, C., TANNER, M. & UTZINGER, J. ( 2002). Polyparasitism with Schistosoma mansoni, geohelminths, and intestinal protozoa in rural Côte d'Ivoire. Journal of Parasitology 88, 461466.Google Scholar
KLOOS, H., DE SOUZA, C., GAZZINELLI, A., SOARES FILHO, B. S., DA COSTA, T., BETHONY, J., PAGE, K., GRZYWACZ, C., LEWIS, F., MINCHELLA, D., LO VERDE, P. & OLIVEIRA, R. C. ( 2001). The distribution of Biomphalaria spp. in different habitats in relation to physical, biological, water contact and cognitive factors in a rural area in Minas Gerais, Brazil. Memorias do Instituto Oswaldo Cruz 96, 5766.Google Scholar
KLOOS, H., FULFORD, A. J., BUTTERWORTH, A. E., STURROCK, R. F., OUMA, J. H., KARIUKI, H. C., THIONGO, F. W., DALTON, P. R. & KLUMPP, R. K. ( 1997). Spatial patterns of human water contact and Schistosoma mansoni transmission and infection in four rural areas in Machakos district, Kenya. Social Science and Medicine 44, 949968.CrossRefGoogle Scholar
KLOOS, H., GAZZINELLI, A. & VAN ZUYLE, P. ( 1998). Microgeographical patterns of schistosomiasis and water contact behavior; examples from Africa and Brazil. Memorias do Instituto Oswaldo Cruz 93 (Suppl. 1), 3750.CrossRefGoogle Scholar
KRISTENSEN, T. K., MALONE, J. B. & McCARROLL, J. C. ( 2001). Use of satellite remote sensing and geographic information systems to model the distribution and abundance of snail intermediate hosts in Africa: a preliminary model for Biomphalaria pfeifferi in Ethiopia. Acta Tropica 79, 7378.CrossRefGoogle Scholar
LENGELER, C., UTZINGER, J. & TANNER, M. ( 2002). Questionnaires for rapid screening of schistosomiasis in sub-Saharan Africa. Bulletin of the World Health Organization 80, 235242.Google Scholar
LEVIN, S. A. ( 1992). The problem of pattern and scale in ecology. Ecology 73, 19431967.CrossRefGoogle Scholar
MALONE, J. B., YILMA, J. M., McCARROLL, J. C., ERKO, B., MUKARATIRWA, S. & ZHOU, X. N. ( 2001). Satellite climatology and the environmental risk of Schistosoma mansoni in Ethiopia and East Africa. Acta Tropica 79, 5972.CrossRefGoogle Scholar
RASO, G., N'GORAN, E. K., TOTY, A., LUGINBÜHL, A., ADJOUA, C. A., TIAN-BI, N. T., BOGOCH, I. I., VOUNATSOU, P., TANNER, M. & UTZINGER, J. ( 2004). Efficacy and side effects of praziquantel against Schistosoma mansoni in a community of western Côte d'Ivoire. Transactions of the Royal Society of Tropical Medicine and Hygiene 98, 1827.CrossRefGoogle Scholar
RASO, G., UTZINGER, J., SILUÉ, K. D., OUATTARA, M., YAPI, A., TOTY, A., MATTHYS, B., VOUNATSOU, P., TANNER, M. & N'GORAN, E. K. ( 2005). Disparities in parasitic infections, perceived ill health and access to health care among poorer and less poor schoolchildren of rural Côte d'Ivoire. Tropical Medicine and International Health 10, 4257.CrossRefGoogle Scholar
RATARD, R. C., KOUEMENI, L. E., BESSALA, M. M., NDAMKOU, C. N., GREER, G. J., SPILSBURY, J. & CLINE, B. L. ( 1990). Human schistosomiasis in Cameroon. I. Distribution of schistosomiasis. American Journal of Tropical Medicine and Hygiene 42, 561572.CrossRefGoogle Scholar
ROBINSON, T. P. ( 2000). Spatial statistics and geographical information systems in epidemiology and public health. Advances in Parasitology 47, 81128.CrossRefGoogle Scholar
SPIEGELHALTER, D. J., BEST, N., CHARLIN, B. P. & VAN DER LINDE, A. ( 2002). Bayesian measures of model complexity and fit. Journal of the Royal Statistical Society, Series B 64, 583639.CrossRefGoogle Scholar
UTZINGER, J., BERGQUIST, R., XIAO, S. H., SINGER, B. H. & TANNER, M. ( 2003). Sustainable schistosomiasis control – the way forward. Lancet 362, 19321934.CrossRefGoogle Scholar
UTZINGER, J., BOOTH, M., N'GORAN, E. K., MÜLLER, I., TANNER, M. & LENGELER, C. ( 2001). Relative contribution of day-to-day and intra-specimen variation in faecal egg counts of Schistosoma mansoni before and after treatment with praziquantel. Parasitology 122, 537544.CrossRefGoogle Scholar
UTZINGER, J., N'GORAN, E. K., OSSEY, Y. A., BOOTH, M., TRAORÉ, M., LOHOURIGNON, K. L., ALLANGBA, A., AHIBA, L. A., TANNER, M. & LENGELER, C. ( 2000). Rapid screening for Schistosoma mansoni in western Côte d'Ivoire using a simple school questionnaire. Bulletin of the World Health Organization 78, 389398.Google Scholar
VAN DER WERF, M. J., DE VLAS, S. J., BROOKER, S., LOOMAN, C. W. N., NAGELKERKE, N. J. D., HABBEMA, J. D. F. & ENGELS, D. ( 2003). Quantification of clinical morbidity associated with schistosome infection in sub-Saharan Africa. Acta Tropica 86, 125139.CrossRefGoogle Scholar
WATTS, S., KHALLAAYOUNE, K., BENSEFIA, R., LAAMRANI, H. & GRYSEELS, B. ( 1998). The study of human behavior and schistosomiasis transmission in an irrigated area in Morocco. Social Science and Medicine 46, 755765.CrossRefGoogle Scholar
world health organization ( 2002). Prevention and Control of Schistosomiasis and Soil-Transmitted Helminthiasis: Report of a WHO Expert Committee. WHO Technical Report Series No. 912. WHO, Geneva.
YANG, G. J., VOUNATSOU, P., ZHOU, X. N., TANNER, M. & UTZINGER, J. ( 2005). A Bayesian-based approach for spatio-temporal modeling of county level prevalence of Schistosoma japonicum infection in Jiangsu province, China. International Journal for Parasitology, 35, 155162.CrossRefGoogle Scholar
ZHOU, X. N., MALONE, J. B., KRISTENSEN, T. K. & BERGQUIST, N. R. ( 2001). Application of geographic information systems and remote sensing to schistosomiasis control in China. Acta Tropica 79, 97106.CrossRefGoogle Scholar