What is the greatest threat to a child's survival? Arguably, shit. Diseases spread through inadequate - sometimes appalling - sanitation in poor countries range from diarrhoea, which kills babies in large numbers, to polio which is crippling if it does not kill.
The world has pledged to halve the number of people without access to decent sanitation - it's one of the Millennium Development targets agreed by donor governments. At the rate we're going, according to Oliver Cumming, health policy officer of Water Aid, who came to see me the other day, sub-Saharan Africa will get there in the 23rd century - we're 300 years off course.
And yet, he points out, access to sanitation has knock-on benefits for other goals. Apart from the obvious huge impact on infant and child mortality, girls stay in school if there are (private and separate) toilets.
Today, the latest the latest UN-Water Global Annual Assessment of Sanitation and Drinking-Water (GLAAS) report arrives - courtesy of Unicef - which supports the case Water Aid were making:
Between 1997 and 2008, aid commitments for sanitation and water fell from 8% of total development aid to 5%, lower than commitments for health, education, transport, energy and agriculture. This drop occurred despite compelling evidence that achieving the water and sanitation target of the Millennium Development Goals (MDGs) would lower health-care costs, increase school attendance and boost productivity. Despite these clear benefits for human and economic development, many countries and donors are still not allocating sufficient attention and resources to water and sanitation.
And this is Dr Maria Neira, WHO Director of Public Health and Environment:
Neglecting sanitation and drinking-water is a strike against progress. Without it, communities and countries will lose the battle against poverty and ill-health... Unsafe water, inadequate sanitation and the lack of hygiene claim the lives of an estimated 2.2 million children under the age of 5 every year. Of these deaths, 1.5 million are due to diarrhoea, the second leading contributor to the global burden of disease. The impact of diarrhoeal disease in children under 15 is greater than the combined impact of HIV and AIDS, malaria, and tuberculosis.
Why is it that something so crucial, something that transformed our lives in affluent countries a hundred years ago, and something over which there are no arguments about how to progress - there is no dispute what is needed - can be so neglected?
It comes back to the s-word. Governments and even UN bodies don't quite feel comfortable with dealing with excreta. Nobody wants to be sanitation minister. It gets put in environment departments instead of health departments and drops off agendas.
Cummings at Water Aid is critical of WHO too, which is enthusiastically backing vaccines for rotavirus against diarrhoea - which will be only partially effective and are not yet rolled out.
"How can WHO push rotavirus vaccines whilst not at the same time putting all its weight and influence behind something as basic as sanitation?" he asks.
Maybe the new report, described as the fruits of a UN-Water pilot initiative led by the WHO, marks a new drive to speed up progress towards the sanitation target. Three hundred years is a scandalously long time to wait.