"This paper indicates that lakes may well be connected at irregular time intervals and that even an apparently isolated lake can breach and transfer water hundreds of kilometres to other distant lakes so the contamination potential in relation to small lakes is greater than we'd previously thought, " he said.

BBC: NEWS | Science/Nature | Secret rivers found in Antarctic

If the scheme were implemented (and the WHO is at pains to point out that this paper in no way indicates a change of policy), it would be more costly to begin with than the existing plan of universal access.

ECONOMIST: AIDS

Nevertheless, this paper serves to demonstrate the need for further reflection and indicates the main issues on the agenda.

UNESCO: Social and Human Sciences