![](https://blog.me.upenn.edu/wp-content/uploads/2024/02/Ganges_River_Delta_600x400-1.jpeg)
“A time and a place for everything.” As true for human experiences as it is for cellular survival, this maxim speaks to the most hopeful and cynical of our beliefs. Without exception, every occasion to suffer or opportunity to thrive is guaranteed, however quietly, to end. But the illusion of forever is a strong one, especially when a crisis lasts long enough to feel permanent.
Pandemics can be like that.
The first cholera pandemic began in South Asia in the early nineteenth century. A British imperial expedition to survey remote swampland in the Ganges Delta encountered water carrying the bacteria now known as Vibrio cholerae. Workers fell ill and died in as little as hours. The disease, spreading rapidly, flourished around the world.
A century later, engineering intervened, playing a starring role in the development of modern infrastructure to store and deliver clean water across astonishing distances. Using mathematics to shape and contain the natural world, engineers relied on fluid mechanics, the physics of flow, to sustain life through pipes.
Cholera — along with other water-borne diseases, such as typhoid and dysentery — saw a steep drop in outbreaks.
But it did not disappear. There have been six additional cholera pandemics since its initial contact with humans, killing tens of millions. Starting in the early 1900s, most of these deaths have occurred in marginalized countries and communities. The current pandemic has been ongoing since the 1960s.
In the early twentieth century, massive infrastructural expansion required science to reshape nature into a utility service, plumbing treated water into homes. Today, researchers at the University of Pennsylvania School of Engineering and Applied Science are working closely with nature on its own terms to understand and predict the movement of microscopic bacteria through flowing water and how this physics is linked to human infection.
Engineers are again turning to fluid mechanics to keep humans safe from cholera, working not at the epic scale of infrastructure but the subtle level of microscopic cells.
Paulo Arratia, Professor in Mechanical Engineering and Applied Mechanics (MEAM) and Boyang Qin, Ph.D. graduate in MEAM and current postdoctoral fellow at Princeton University, have found that keeping communities safe from cholera is a matter of time, debuting groundbreaking research that lays the foundation for water security interventions to disrupt the motility and reproduction of pathogens.
This article was written by Devorah Fischler for Penn Engineering Today. Click here to read the full article.