Acceptance and use of communal filtration units in guinea worm eradication

The use of cloth to filter drinking water for guinea worm prevention is a l ong-standing control strategy and part of a mixed approach that includes th e provision of wells, chemical treatment of ponds and protection of water s upplies. As the goal of eradication nears, filters are a useful component o f the quick response needed to implement case containment at village level. Various designs of filters have been used. Individual hand-sewn filters (H SFs) using monofilament nylon cloth have played a central role in village-b ased control to date. Problems such as the need to continually reinforce co rrect habitual filtering behaviour have led to the design and testing of co mmunal filtration units (CFUs) made from metal oil drums with filter cloth inserted in the top and spigots at the bottom. Approximately one year after the introduction of CFUs in the South-western Zone of Nigeria, village sur veys were conducted to determine opinions about the two types of filters an d reported use. Percentage use was calculated by dividing the number of tim es water was filtered in the week preceding the survey by the number of tim es water was collected in that week. Those respondents with access to CFUs filtered an average of 91.9% of the time compared to 75.7% of those with HS Fs. Using the village as level of analysis since it was the main level of i ntervention, the average percent of times villagers in CFU villages filtere d was 91.1% compared to 77.8% in HSF villages. Although CFUs were more expe nsive in the short run, their greater acceptance by villagers is a factor t o recommend their wider implementation to speed up elimination of guinea wo rm from Nigeria.