The pictures — of children with sunken eyes and shriveled skin; oxen being herded across a river where women clean their clothes and fill their pitchers; an African villager sipping water from a shallow puddle — made the point like no words could at the May 11 Center for International Development symposium “The Impact of the Global Water Crisis on Health and Human Development” at the Harvard School of Public Health (HSPH). Still, the statistics were almost equally startling: More than a billion people worldwide lack safe water sources, and 2.6 billion — 40 percent of the world’s population — have no basic sanitation. Nearly 2 million people a year, 90 percent of them children under 5, die from dehydration and associated malnutrition and microbial diseases.

The conference got under way with an introductory talk by Richard Cash, an HSPH senior lecturer on international health and pioneer in oral rehydration therapy. Cash’s work in researching and introducing a simple saltwater-glucose solution that helps replenish the fluids lost during diarrheal illnesses is estimated to have saved the lives of 40 million to 50 million children worldwide since the early 1970s. He discussed water, sanitation, and health at the village level, pointing out that improved water quality can decrease waterborne diarrheal diseases such as cholera and hepatitis A, while increased water quantity can improve hygiene and sanitation.