Oral Saline

Most Indian families have, at some point, torn open a little sachet of ORS, stirred the powder into a litre of water and coaxed an ill child into drinking it. The treatment got its decisive test in the monsoon of 1971, in a cholera camp at Bangaon in West Bengal, after the intravenous fluid ran out and a paediatrician handed the job to the patients' relatives, with cups.

The paediatrician was Dilip Mahalanabis. The families kept begging for saline, meaning the drip, so he told them this was saline too, given by mouth. He called it oral saline.

How cholera kills

Cholera doesn't wreck the gut. The bacterium sits in the small intestine and releases a toxin that drives up a chemical messenger called cyclic AMP inside the cells of the gut lining, and those cells start pushing salt and water out into the bowel. With inadequate treatment, somewhere around 30 to 40 per cent of severe cases die.

For most of the twentieth century the reliable treatment was to put the fluid straight back through a vein. That works, and it is expensive in every way that matters in a crisis. It needs sterile fluid, needles, and people trained to find a vein in someone who is collapsing. Dhiman Barua, who worked on cholera at the World Health Organization, later described the logistics. Saline then came in glass bottles, and a one litre bottle was so heavy that flying it anywhere cost many times more than the fluid inside. In 1970, with cholera in 40 African countries, WHO simply could not ship enough.

The trick in the gut

On 24 August 1960, at a symposium in Prague, an American biochemist named Robert Crane proposed "for the first time anywhere that the fluxes of an ion and a substrate could be coupled by combining with the same reversible transport carrier in the cell membrane."

The carrier that lets glucose into the cells lining the small intestine takes sodium in with it, and water follows the salt. The cholera toxin leaves that carrier working. So if a patient drinks a solution with glucose and sodium in the right proportions, the gut keeps absorbing fluid at the top while the toxin pours it out lower down, and the patient can be kept ahead of the losses without a needle.

That physiology is what the Lancet was praising in its famous editorial of 5 August 1978, "Water with sugar and salt". The line is nearly always quoted as calling ORS the greatest advance of the century. What it said was this:

"The discovery that sodium transport and glucose transport are coupled in the small intestine, so that glucose accelerates absorption of solute and water, was potentially the most important medical advance this century."

The hospital trials

By 1967 and 1968, teams at the Johns Hopkins centre in Calcutta and at a cholera research laboratory further east had shown on hospital wards that a glucose and salt solution could rehydrate adults with cholera. Nathaniel Pierce, Norbert Hirschhorn, David Nalin and Richard Cash were among the names. One 1968 trial found the oral solution cut the intravenous fluid patients needed by about 80 per cent.

Those trials ran under controlled conditions, with doctors measuring every litre in and out. Nobody had shown it could work in a field, at scale, in the hands of people with no training at all. Most hospital doctors assumed it could not.

Bangaon, 1971

That summer millions of people fled a war across the eastern border into West Bengal. The monsoon broke over the camps, and cholera followed.

Mahalanabis had been at the Johns Hopkins centre in Calcutta since 1966, measuring how much salt and water children lost in cholera. He went to Bangaon. According to an obituary written by colleagues who had worked alongside him, thirty per cent of the cholera patients in the camp were dying, there was hardly any intravenous fluid, and there were only two medical staff to give it.

He bought glucose, salt and baking soda at the local market and had them weighed into cellophane packets, each enough for a litre once dissolved. Barua visited, and remembered it decades later:

"I saw an incredible number of sick and dehydrated people lying on the floor there. Mahalanabis kept drums of oral rehydration fluid each with a nozzle on the side and told relatives to fetch the solution in cups and mugs to feed the patients."

What little intravenous fluid there was went to the severest cases. Everyone else drank.

The team published the results in the Johns Hopkins Medical Journal in 1973. Of 3,703 patients admitted to the Bongaon treatment centre, as the paper spelled it, the overall case fatality ratio was 3.6 per cent. In a special demonstration unit that treated 1,190 of them it was 1 per cent. The abstract gives no figure for the other camps; the one-tenth comparison comes from his colleagues. The authors noted that "extremely adverse logistic and administrative conditions prevailed", and listed the drink's advantages, among them "safety in the hands of inexperienced personnel after only brief instructions."

Barua said that what he saw in Bangaon convinced him WHO had been right to let minimally trained people give the solution.

Who gets the credit

Mahalanabis died in Kolkata on 16 October 2022, aged 87. Many tributes said he had invented ORS and nobly declined to patent it. Neither is right, and he never claimed otherwise. The 1973 paper opens by citing the earlier work it rested on and describes itself as "confirmation" of what the hospital trials had found. His contribution was the one the wards could not supply: proof that it worked in a disaster.

In January 2023 the government named him for the Padma Vibhushan, posthumously. He had already shared the Pollin Prize for paediatric research in 2002 and the Prince Mahidol Award in 2006.

Why doctors held out

Acceptance took years. Barua put the reason bluntly: "Hospital doctors regarded oral rehydration therapy as a second-class treatment." In the end WHO and UNICEF settled on a single formula for all ages, later reduced in strength, and from 2004 recommended zinc alongside it, which shortens an episode of diarrhoea by about a quarter.

Barua reckoned that diarrhoea killed about five million children under five a year in the 1950s and 1960s, and around two million by the late 1980s and 1990s. He was careful to say the drink was not the only reason.

Who still dies

WHO's fact sheet puts the toll at 443,832 children under five a year, plus 50,851 aged five to nine. UNICEF's newer estimate for 2024 is about 374,000 under-fives. The two estimates differ, and neither is small. UNICEF says a full course of ORS and zinc costs well under one US dollar, and that only 22 per cent of children with diarrhoea get both.

India is doing better than that average, and not well enough. In the fifth National Family Health Survey, run from 2019 to 2021, 60.6 per cent of children under five who'd had diarrhoea in the previous fortnight were given ORS, up from 50.6 per cent five years earlier. Only 30.5 per cent got zinc. And 68.9 per cent were taken to a health facility or provider, and being seen by somebody turns out to be no guarantee of the sachet.

The clinic counter

A study published in Science in 2024 sent actors into the clinics and pharmacies of more than 2,000 providers in 253 towns in Karnataka and Bihar, each playing a parent with a two-year-old who had diarrhoea. When the actor stated no preference, 28 per cent of providers gave ORS. In the same group, 69 per cent gave antibiotics.

When the actor asked for ORS, prescribing jumped by 27 percentage points. The researchers estimated that providers' mistaken belief that patients don't want ORS explained 42 per cent of the under-prescribing. Stock-outs explained about 6 per cent and financial incentives about 5.

The shelves had their own problem. For years, sugary fruit drinks carried the letters ORS in their names. A Hyderabad paediatrician, Sivaranjani Santosh, campaigned against them for eight years. In orders of 14 and 15 October 2025 the Food Safety and Standards Authority of India barred the term from drink names, labels and advertisements, and within weeks the Delhi High Court refused a manufacturer's plea against the ban, citing the risk to people who actually need rehydration.

The fix in Bangaon was a name. Families wanted saline, so the drink in the drums became saline, and they carried it back to the floor in their own mugs.

Sources

• D. Mahalanabis, A. B. Choudhuri, N. G. Bagchi, A. K. Bhattacharya and T. W. Simpson, Johns Hopkins Medical Journal, 1973, PubMed record of the 1973 paper on oral fluid therapy of cholera among refugees at Bongaon (the 3,703 patients and 3.6 per cent fatality; the demonstration unit's 1,190 patients at 1 per cent; the quoted lines on conditions and on inexperienced personnel; the work described as confirmation).
• Nita Bhandari, Norbert Hirschhorn, Nathaniel Pierce, David A. Sack and Mathuram Santosham, The National Medical Journal of India, "Dilip Mahalanabis (12 November 1934-16 October 2022)" (thirty per cent of the camp's cholera patients dying; the market ingredients and cellophane packets; two medical staff; the name oral saline; 3.6 per cent as one tenth of the rate elsewhere; his career, prizes and death).
• Bulletin of the World Health Organization, "Miracle cure for an old scourge", 2009 (Barua on glass saline bottles, cholera in 40 African countries in 1970, the Bangaon drums and cups, doctors calling it second-class, and under-five deaths falling from about five million to about two million).
• William B. Greenough III, Journal of Clinical Investigation, "The human, societal, and scientific legacy of cholera" (how the toxin causes secretion; sodium-glucose transport surviving cholera; 30 to 40 per cent mortality with inadequate treatment; the Lancet editorial's wording).
• Kirk L. Hamilton, Frontiers in Physiology, "Robert K. Crane - Na+-glucose cotransporter to cure?" (Crane's quoted account of his Prague lecture of 24 August 1960).
• Kiran Kumbhar, The Wire, "Who Owns a Scientific Invention?: The Truth About ORS" (the false invention and patent claims, and the Lancet editorial praising the physiology rather than ORS).
• Mustafa Mahfuz, A. K. M. Tariful Islam Khan and Mohammad Yunus, Indian Journal of Medical Research, "Development of oral rehydration salt solution: A triumph of medical science" (the 1967 and 1968 hospital trials, their researchers, and the 80 per cent cut in intravenous fluid).
• Press Information Bureau, "Padma Awards 2023 announced" (the posthumous Padma Vibhushan).
• World Health Organization, "Diarrhoeal disease" (443,832 under-five and 50,851 five-to-nine deaths a year; zinc shortening episodes by 25 per cent).
• World Health Organization, "Zinc supplementation in the management of diarrhoea" (the 2004 recommendation of low-osmolarity ORS with zinc).
• UNICEF Supply Division, "Market update: Oral rehydration salts (ORS) and zinc" (about 374,000 under-five deaths in 2024; a course under one US dollar; 22 per cent coverage of ORS with zinc).
• Ministry of Health and Family Welfare, "National Family Health Survey - 5, India Fact Sheet" (the ORS, zinc and care-seeking percentages for 2019-21 and 2015-16).
• Zachary Wagner, Manoj Mohanan, Rushil Zutshi, Arnab Mukherji and Neeraj Sood, Science, "What drives poor quality of care for child diarrhea? Experimental evidence from India" (the standardised patient study and all its figures).
• The Tribune, "No more 'ORS' confusion, here is why FSSAI bans term on food products" (the FSSAI ban and Sivaranjani Santosh's eight-year campaign).
• Nupur Thapliyal, LiveLaw, "Delhi High Court Rejects Plea Against FSSAI Decision To Ban 'ORS' Labelling On Beverages, Cites Adverse Health Outcomes" (the orders of 14 and 15 October 2025 and the court's refusal to interfere).