"Diseases related to inadequate water, sanitation and hygiene are a huge burden in developing countries. It is estimated that 88% of diarrhoeal disease is caused by unsafe water supply, and inadequate sanitation and hygiene (WHO, 2004c). Many schools serve communities that have a high prevalence of diseases related to inadequate water supply, sanitation and hygiene, and where child malnutrition and other underlying health problems are common. Schools, particularly those in rural areas, often completely lack drinking-water and sanitation and handwashing facilities; alternatively, where such facilities do exist they are often inadequate in both quality and quantity. Schools with poor water, sanitation and hygiene conditions, and intense levels of person-to-person contact, are high-risk environments for children and staff, and exacerbate children's particular susceptibility to environmental health hazards. Children's ability to learn may be affected by inadequate water, sanitation and hygiene conditions in several ways. These include helminth infections (which affect hundreds of millions of school-age children), long-term exposure to chemical contaminants in water (e.g. lead and arsenic), diarrhoeal diseases and malaria infections, all of which force many schoolchildren to be absent from school. Poor environmental conditions in the classroom can also make both teaching and learning very difficult. Girls and boys are likely to be affected in different ways by inadequate water, sanitation and hygiene conditions in schools, and this may contribute to unequal learning opportunities. Sometimes, girls and female teachers are more affected than boys because the lack of sanitary facilities means that they cannot attend school during menstruation. The international policy environment increasingly reflects these issues. Providing adequate levels of water supply, sanitation and hygiene in schools is of direct relevance to the United Nations (UN) Millennium Development Goals of achieving universal primary education, promoting gender equality and reducing child mortality. It is also supportive of other goals, especially those on major diseases and infant mortality." - p. iii

"The global disruption to education caused by the COVD-19 pandemic is without parallel and the effects on learning are severe. The crisis brought education systems across the world to a halt, with school closures affecting more than 1.6 billion learners. While nearly every country in the world offered remote learning opportunities for students, the quality and reach of such initiatives varied greatly and were at best partial substitutes for in-person learning. Now, 21 months later, schools remain closed for millions of children and youth, and millions more are at risk of never returning to education. Evidence of the detrimental impacts of school closures on children's learning offer a harrowing reality: learning losses are substantial, with the most marginalized children and youth often disproportionately affected. Countries have an opportunity to accelerate learning recovery and make schools more efficient, equitable, and resilient by building on investments made and lessons learned during the crisis. Now is the time to shift from crisis to recovery - and beyond recovery, to resilient and transformative education systems that truly deliver learning and well-being for all children and youth."--The World Bank website.

This volume describes the methods used in the surveillance of drinking water quality in the light of the special problems of small-community supplies, particularly in developing countries, and outlines the strategies necessary to ensure that surveillance is effective.