Hand-washing and its impact on child health in Kathmandu, Nepal

Abstract

Gut damage, resulting in maldigestion or malabsorption of food and stimulation of the immune system, has been linked to growth faltering in young children in the developing world. Gut damage occurs along a spectrum, with only the more severe damage resulting in visible symptoms such as diarrhoea; most gut damage in young children is sub-clinical but chronic, and over time it can have a significant impact on a child’s growth rate. Hand-washing with soap has been found to reduce the risk of diarrhoea by 42-47%. Would this simple intervention also reduce the sub-clinical yet chronic form of gut damage associated with childhood growth faltering? Framed within the bio-cultural research paradigm, and theoretically informed by insights from Critical Medical Anthropology, this study used a mixed-method, longitudinal approach in order to investigate this question.
Eighty-eight children aged 3-12 months were recruited from eight slum communities in Kathmandu, Nepal. Each community was allocated to a control or intervention group (n=43 and 45 children, respectively). In intervention areas, a community-based hand-washing with soap programme was devised and implemented for six months; in control areas, mothers continued their normal practices. The intervention was evaluated by comparing five outcomes: rates of maternal hand-washing, levels of child morbidity, gut damage, immune stimulation and growth faltering in the two groups.
Hand-washing rates increased amongst intervention mothers: by the end of the intervention, mothers living in hand-washing areas were more likely to report hand-washing with soap after cleaning the baby’s bottom and before cooking, eating or feeding the child (for all, P<.01). As a result, children in the intervention areas experienced a decrease in both the number of diarrhoeal episodes (3.0 vs. 4.3 episodes, P=.049) and the number of days with diarrhoeal symptoms over the period of study (9.67 vs. 16.33 days, P=.023).
Yet, despite reducing diarrhoeal morbidity, hand-washing had no impact on the biochemical or growth status of the children: there was no significant reduction in levels of gut damage or immune stimulation in children from intervention areas over the period of the study. Consequently there was no improvement in growth rates for these children, as measured by height-for-age, weight-for-age and weight-for-height z-scores.
This study concludes that when children live in highly contaminated, over-crowded environments, with poor access to clean water and sanitation, selective interventions focusing on one small behavioural change are unlikely to have an impact. In such highly contaminated environments, faecal contamination of hands is just one of the many pathways by which these children are exposed to pathogenic organisms. The biggest threat to the health of these children is not poor hygiene behaviour, but life in the slum. Comprehensive strategies to provide basic services and raise general standards of living in the slums are the best way in which to have a significant impact: piecemeal interventions focusing on single issues risk being ineffective both in terms of health impact and cost-effectiveness. This point is situated within the literature on effective and sustainable health interventions and the wider social and political debates surrounding global public health policy and practice in the 21st Century.