The medicine that tasted wrong

A programme distributing a nutritional supplement in several districts reported a strange pattern. Uptake was high in some villages and close to zero in others, with no difference in need, cost or distance.

The explanation was taste. The supplement had a slightly metallic flavour that most adults ignored and most children refused. In villages where the first family to try it had an older child, the child complained and the news travelled. In villages where the first family had a baby, nobody complained, and uptake stayed high.

The programme had tested the supplement for safety, for nutritional content and for shelf life in heat. It had not tested whether children would swallow it twice.

This category of failure is common and has a name among people who design such programmes: the last metre. Enormous effort goes into producing something and delivering it to the village, and the final step — a person actually using it, repeatedly, without being watched — receives the least attention and decides the outcome.

The fix was ordinary. A flavouring was added, the cost rose by a small amount, and uptake in the low villages rose within two months. What is worth noticing is how late the problem was found. A single afternoon spent watching twenty children take the second dose would have found it before a year of distribution did.