Oral Rehydration Therapy Saves a Million Lives a Year With Salt and Sugar

During the 1971 Bangladesh Liberation War, cholera tore through refugee camps holding millions of displaced people. Physicians had intravenous fluid but not enough of it, not enough staff to administer it, and no way to supply it at the scale the outbreak required. Dilip Mahalanabis, an Indian physician working for the International Centre for Diarrhoeal Disease Research, instructed community health workers to mix and distribute a simple oral solution — salt, sodium bicarbonate, glucose, and water — in volumes keyed to fluid loss. The case fatality rate in his camps dropped from over 30% to under 4%.

The solution worked because of a mechanism identified in the 1960s by researchers Robert Crane, Norbert Hirschhorn, and David Nalin studying glucose-sodium co-transport in the intestine. Even when the gut wall is ravaged by cholera toxin and secreting water rather than absorbing it, the glucose-sodium co-transporter (SGLT1) keeps functioning. Glucose and sodium enter the intestinal cell together, and water follows. The toxin disrupts one mechanism; the co-transporter is a second, parallel pathway that the formula exploits.

The World Health Organization standardized the formula in 1975. The version now recommended uses 2.6 grams of sodium chloride, 2.9 grams of trisodium citrate, 1.5 grams of potassium chloride, and 13.5 grams of anhydrous glucose per liter of water. It costs roughly 50 cents per liter to produce at scale.

The Lancet described ORT in a 1978 editorial as "potentially the most important medical advance of the 20th century." The description sounds like hyperbole. The numbers suggest it isn't. Before widespread ORT deployment, diarrheal disease killed an estimated 5 million children per year globally. The current figure is under 500,000, though improved sanitation, nutrition, and access to care share the credit.

Mahalanabis received the Prince Mahidol Award in 2002 for his Bangladesh field work. The formula he mixed in 1971 is still the one WHO recommends today.