Water Sanitation and Hygiene. Children’s health and nutritional well-being are strongly linked to their access to safe water and proper sanitation and hygiene. … Frequently poor hygiene and sanitation practices combined with the use of unsafe water cause chronic and/or acute diarrhea and Hygiene. Children’s health and nutritional well-being are strongly linked to their access to safe water and proper sanitation and hygiene. … Frequently poor hygiene and sanitation practices combined with the use of unsafe water cause chronic and/or acute diarrhea.and Hygiene. Children’s health and nutritional well-being are strongly linked to their access to safe water and proper sanitation and hygiene. … Frequently poor hygiene and sanitation practices combined with the use of unsafe water cause chronic and/or acute diarrhea.