Richard A Cash, a public health pioneer whose work showed that a simple mix of salt, sugar, and water could treat cholera and other diarrheal diseases, passed away on October 22, 2024, at his Cambridge, Massachusetts home. He was 83. His dear wife, Stella Dupuis, shared that the cause of his death was brain cancer.

In the 1960s, diseases like cholera and dysentery killed about five million children annually due to dehydration. Dr Cash described how patients could quickly deteriorate, saying they went “from a grape to a raisin” in hours. While rehydration could save lives, intravenous drips — the standard treatment — were often unavailable in poor communities. In 1967, Dr Cash joined a US Public Health Service project in East Pakistan (now Bangladesh). There, with fellow doctor David Nalin, he helped develop the oral rehydration therapy (ORT) that has since saved an estimated 50 million lives.

I want to share more than just the story of a global public health icon. I want to highlight through a few stories, the person I came to know and deeply admire since we first met. I first met Richard in late 1993 during his visits to Dhaka, Bangladesh. At the time, I had just started working as a junior anthropologist at BRAC, one of the largest NGOs in the Global South. Richard was close to BRAC’s founder, the late Fazle Hasan Abed, and had a deep love for the country and its people. He often visited the Research and Evaluation Unit to support staff, and it was there that we formed a deep friendship that lasted over two decades. Richard quickly became both a mentor and a close friend. He shared his extensive knowledge of public health with humility and warmth, always eager to discuss and debate ideas and he truly valued what others had to say, making every conversation productive and meaningful.

Richard was one of the key people, along with a few others, who worked closely with the late Fazle Hasan Abed to set up the BRAC James P Grant School of Public Health at BRAC University in 2004. I reconnected with him when I joined the school that same year. He was loved by students and colleagues alike, and news of his passing shocked everyone. Richard was always kind, gentle, and incredibly generous. Every year, when he came to teach the Epidemiology of Infectious Diseases module, he would bring sweets and nuts for our Master of Public Health (MPH) students, who came from all over the world, including Bangladesh. He never accepted payment for his teaching hours, instead quietly donating his honorarium/stipend to set up a small fund that supported students’ extracurricular activities. He was deeply passionate about inspiring and supporting our diverse group of students in their public health journeys. He encouraged their growth with care; always finding opportunities to help them thrive. He remained committed to teaching in the MPH programme until the end.

Beyond his professional brilliance, Richard had an eclectic taste in books and a talent for recommending thought-provoking documentaries and books. Thanks to him, I discovered Chimamanda Ngozi Adichie’s post-colonial feminist writings and other inspiring authors. I still remember when he handed me his copy of her book, Purple Hibiscus — a powerful story about domestic violence — saying, “Sabina, keep this…you should read this. It’s dark but incredibly compelling.” He was a passionate reader, endlessly curious about the world and the people in it. Richard had a special love for Bangladesh. I fondly recall visiting his office at Harvard — it was a tribute to the country, filled with pictures, handicrafts, and writings about Bangladesh. He was always eager to hear updates about the school, Bangladesh and my research work. He would ask probing questions, share insights, and offer valuable feedback that deeply enriched my work.

Richard was a very sensitive and caring soul who always looked out for his friends. When my father was critically ill, we had long conversations about life, death, and loss. During that time, he gifted me Atul Gawande’s Being Mortal, a book about more than just dying — it was about living fully, with autonomy, dignity, and joy, even in one’s final days. This helped me deal with my father’s impending passing in mid-January 2020. With Richard’s encouragement, I spent three months at Harvard on a fellowship working on my book, in mid-2022. He not only read my drafts and gave thoughtful feedback but also graciously agreed to write the foreword. Over the years, I’ve met many of Richard’s colleagues and friends whom he supported — whether through facilitating tuition waivers, writing recommendations for talented young professionals, offering his home to countless people who needed a place to stay when in Boston, and connecting them with his extensive network of colleagues in Bangladesh and beyond. He was incredibly generous in his support of others, always doing so quietly and without fanfare.

During my three months in Boston in 2022, I grew close to his soulmate — Stella — a passionate, and incredibly kind and caring person. They welcomed me with open arms, looked after me, and made me feel completely at home. What I cherish now more than ever are the simple, heartfelt moments we spent together in 2022. Sitting on their backyard veranda, feeding turkeys and other birds, and enjoying time in the garden, we had deep conversations about public health challenges, spirituality (Stella’s passion), politics and the importance of being ethical, committed and service oriented in public health. I also have cherished memories of strolling through Cambridge with Richard as he pointed out buildings, museums, and local parks. Richard had a sweet tooth, and we often wandered over to Peet’s Pies, a nearby bakery, where he would regularly treat himself to a pie or two — much to Stella’s amusement and concern, as he was meant to limit his consumption of desserts!

The last time I saw Richard was in November 2023, during a work trip to Boston. Earlier that year, when he visited Dhaka to teach, he mentioned that he wouldn’t be returning to teach in person in 2024, because “the journey was too long.” I was deeply saddened by this news but still held onto the hope that we might convince him to return in person someday. When I travelled to attend a meeting in Boston, Richard and Stella took me to one of their favorite restaurants. As usual, we covered a wide range of topics over dinner. I will miss his humor, sharp wit, and vast knowledge — not just about public health, but also politics, religion, history, current events, and so much more. Richard was someone I deeply respected and admired for living life on his own terms. He was not driven by the traditional ambitions that often fuel people in our field. Instead, he was ambitious and passionate about making a meaningful impact on the health and lives of vulnerable people — through his pioneering work with ORT, his research, and his dedication to teaching and mentoring countless students and colleagues, including me.

Even after receiving the prestigious Prince Mahidol Award, he remained humble and grounded. Meeting Richard was truly a transformative experience for me. He was an exceptional and rare individual, and his loss will be deeply felt by all who loved him.