Many schools in poorer countries lack adequate water and sanitation facilities, affecting children's educations and even claiming lives, the United Nations Children's Fund (UNICEF) warns in a new report on Monday.

"Millions of children in the developing world go to schools which have no drinking water or clean latrines -- basic things that many of us take for granted," said Sigrid Kaag, the agency's Regional Director for the Middle East and North Africa, at the publication's launch on Monday in Dubai.

Produced with the UN World Health Organization (WHO) and partner non-governmental organizations (NGOs), the report notes that 1.5 million children under the age of five die every year of diarrhoea due to unsafe water, inadequate sanitation and lack of hygiene.

Better water, sanitation and hygiene -- collectively known as WASH -- could reverse the trend of nearly 300 million school days being missed worldwide due to diarrhoea, it states. Improved hygiene will lead to less risk of disease, which in turn will result in stepped up school attendance and ultimately nations' economic growth.

WASH also enhances girls' continuation of their education, notes the new publication, entitled Raising Clean Hands: Advancing Learning, Health and Participation through WASH in Schools.

Kaag pointed out that improving sanitation in schools will help to achieve the Millennium Development Goals (MDGs), notably the targets of reducing child mortality and halving the proportion of people without access to safe water and basic sanitation.

Providing WASH in schools, the report says, will require the involvement of all segments of society, including communities, media, students and the private sector.