Sevilla-Casas E
Departamento de Ciencias Sociales, Universidad del Valle, Cali, Colombia.
Soc Sci Med. 1993 Nov;37(9):1155-67. doi: 10.1016/0277-9536(93)90255-3.
This paper develops and tests a methodology for examining the manner and the extent to which human mobility can be associated with malaria risk within an endemic area. The paper presents entomological, epidemiological 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 economic 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 of transmission, microscopic analysis of parasitaemia was found to underestimate 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 increases with age particularly from adolescence onwards. Since mobility for agricultural purposes involves able-bodied males and females, there seems ample justification for concluding that human mobility into certain areas increases the risk of infection for adults, particularly when such mobility coincides with peak rainfall and vector densities. Micro-level data are critical in pinpointing causation and small area variations in risk. Thus the beach area is a high risk area within the delta region, particularly for adults, and this 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 and locating areas and groups at highest risk; using such information to achieve intensive coverage on a small scale may be more cost-effective than attempting to achieve vector or chemotherapeutic control over a wider area for all groups.
本文开发并测试了一种方法，用于研究在疟疾流行地区人类流动与疟疾风险相关的方式和程度。本文展示了从宏观数据和微观数据中获得的昆虫学、流行病学和流动情况结果。结果表明，疟疾集中在纳亚河流域的三角洲地区，由于经济原因，人们在媒介密度高的时候进入该地区。高人口密度与高媒介密度相结合，确保了疟疾的持续和高强度传播。在试图测量传播强度时，发现对寄生虫血症的显微镜分析低估了流行率，显示其非常低或可忽略不计，而同期收集的血清学数据表明流行率很高，且男女相似。血清学数据还表明，流行率随年龄增长而增加，尤其是从青春期开始。由于农业目的的流动涉及健全的男性和女性，因此有充分的理由得出结论，即人类向某些地区的流动会增加成年人的感染风险，特别是当这种流动与降雨高峰和媒介密度同时发生时。微观层面的数据对于确定因果关系和风险的小区域差异至关重要。因此，海滩地区是三角洲地区的高风险区域，尤其是对成年人来说，这可能是因为海滩环境中媒介叮咬率高。一个结论是，行为的微观分析与流行病学数据相结合，在定义和定位风险最高的地区和群体时特别有用；利用这些信息在小范围内实现密集覆盖可能比试图在更广泛区域对所有群体进行媒介或化疗控制更具成本效益。
