HUMAN MOBILITY AND MALARIA RISK IN THE NAYA RIVER BASIN OF COLOMBIA

Authors
Citation
E. Sevillacasas, HUMAN MOBILITY AND MALARIA RISK IN THE NAYA RIVER BASIN OF COLOMBIA, Social science & medicine, 37(9), 1993, pp. 1155-1167
Citations number
54
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Social Sciences, Biomedical
Journal title
ISSN journal
0277-9536
Volume
37
Issue
9
Year of publication
1993
Pages
1155 - 1167
Database
ISI
SICI code
0277-9536(1993)37:9<1155:HMAMRI>2.0.ZU;2-1
Abstract
This paper develops and tests a methodology for examining the manner a nd the extent to which human mobility can be associated with malaria r isk within an endemic area. The paper presents entomological, epidemio logical and mobility results obtained from macro data and micro data. Results indicate that malaria is concentrated in the delta zone of the Naya river basin where the circulation of people into this zone for e conomic reasons occurs at a time when vector densities are high. High human density combined with high vector density ensures continuous and intense transmission of malaria. In attempting to measure intensity o f transmission, microscopic analysis of parasitaemia was found to unde restimate prevalence showing it to be very low or negligible, whereas serological data collected during the same period of time reveal that prevalence is high, and similar for both sexes. Serological data also indicate that prevalence increase's with age particularly from adolesc ence onwards. Since mobility for agricultural purposes involves able-b odied males and females, there seems ample justification for concludin g that human mobility into certain areas increases the risk of infecti on for adults, particularly when such mobility coincides with peak rai nfall and vector densities. Micro-level data are critical in pinpointi ng causation and small area variations in risk. Thus the beach area is a high risk area within the delta region, particularly for adults, an d his is likely to be because of high vector biting rates in the beach environment. One conclusion is that micro analysis of behaviour, when linked to epidemiological data are particularly useful in defining an d locating areas and groups at highest risk; using such information to achieve intensive coverage on a small scale may be more cost-effectiv e than attempting to achieve vector or chemotherapeutic control over a wider area for all groups.