Decades ago, I missed my college graduation ceremony with President Clinton as the commencement speaker because I had to be elsewhere. I was in Shanghai, celebrating the 80th anniversary of the Chinese Medical Association—an organization founded by my great-grandfather, Wu Lien-teh, who was the first Chinese person to be nominated for a Nobel Prize. My father, his grandson, had immigrated to the U.S. from Beijing, met my mother in Palo Alto, and settled our family in Silicon Valley. He brought tales of Wu Lien-teh with him.

In 1910, my father told me, a plague swept through Northeast China. Victims spiked fevers and suffered coughing fits as their skin turned purple, often dying within days. Desperate government authorities summoned my great-grandfather, a 31-year-old physician and infectious disease expert. He traveled to the region by train, arriving on Christmas Eve, 1910, when the temperature was -30 degrees.

At that time, no one knew what caused the disease, and bodies piled up as the Lunar New Year, the most important holiday in Chinese culture, approached. Officials feared the disease would spread rapidly as families returned home to celebrate. Lien-teh, who had studied infections in Europe, discovered that the plague spread through coughs. To stop its transmission, he invented a mask, a forerunner to the N95, made from layers of cotton and gauze.

Battling racism—a French doctor dismissed him as a “Chinaman”—as well as the virus, Lien-teh and his mask brought the plague to an end in the spring of 1911.

I had heard these stories and knew them by heart, but their significance didn’t truly hit me until that stifling day in May 1995 when my father and I landed in Shanghai for the medical association conference. Cousins and extended family greeted and feted us with a 10-course banquet, replete with delights like Chinese candied bananas.

That week, doctors paraded onto the conference stage to testify to the achievements of Lien-teh, who, after ending the plague, set up hospitals in China that blended Western and Chinese medicine. He was nominated for the Nobel Prize in Physiology or Medicine in 1935.

My Mandarin, despite years of Friday night lessons, was too shaky for me to understand all the speakers said. But the passion with which they spoke was unmistakable. Touched by their words, I spent the following summer in Taiwan with my aunt, where my Mandarin improved, and my connection to my roots deepened.

I returned to the U.S. and became an emergency medicine doctor in Boston. Then, in March 2020, I faced a plague of my own. Previously healthy people flooded our intensive care unit and needed ventilators to breathe. Suddenly, the terror my great-grandfather must have felt became real in a way it never had before.

As the pandemic wore on, my children became my solace. But as I curled up at night with my 6-year-old daughter, we noticed something in the stories we read: the heroes never looked like us. We resolved to change that. Together, we wrote a children’s book, Masked Hero, about my great-grandfather, a bespectacled man who stood about 5 feet tall.

He grew up in Malaysia with ten brothers and sisters, in a house with no electricity, studying by lantern at night. He won a scholarship to attend prestigious Cambridge University, only to face discrimination when he returned to Malaysia, then a British colony, and sought a government job. Yet, throughout his life, nothing stopped him—not the severe typhoid he suffered as a child, the rejection from his native country, or the sneers of some doctors in plague-stricken China who refused to believe in his masks.

Now it is up to us, his descendants, to carry on his legacy of benevolence, resilience, and scientific curiosity. We aim to show children that heroes come from all races, genders, and geographies. We hope our book is a small part of that.

Shan Liu is an attending physician in the department of emergency medicine at Massachusetts General Hospital. She earned her MD from Harvard Medical School, her doctorate in science in health policy from Harvard School of Public Health, and completed her residency at the Harvard Affiliated Emergency Medicine Residency Program. Currently, she is an associate professor of emergency medicine at Harvard Medical School and serves as the MGH Geriatric Emergency Medicine Division Fellowship Director. She is the co-author of Masked Hero: How Wu-Lien Teh Invented the Mask and Ended an Epidemic and can be reached at her website and Instagram @shanwliu and @maskedhero_wulienteh.