ASU Professor Paul Westerhoff selected for 2019 Clarke Prize

July 30, 2019

Arizona State University Regents Professor Paul Westerhoff has been named the 2019 Clarke Prize laureate by the National Water Research Institute for outstanding achievement in water science and technology. Westerhoff will receive a medal and a $50,000 prize. 

The Athalie Richardson Irvine Clarke Prize is one of the most prestigious awards in the world presented to active researchers and practitioners making significant advances in water technology. Clarke Prize laureates demonstrate excellence through their continuous contributions to the body of knowledge related to protecting, maintaining, treating and reclaiming water resources.  ASU Regents Professor of Environmental Engineering Paul Westerhoff Paul Westerhoff has been selected for the 2019 Clarke Prize, one of the most prestigious awards in the world for water research. Download Full Image

“It is an incredible honor to be named among such an accomplished group of scientists and engineers,” said Westerhoff, the Fulton Chair of Environmental Engineering in the Ira A. Fulton Schools of Engineering and a senior sustainability scientist at the Julie Ann Wrigley Global Institute of Sustainability. “This would not be possible without great students, awesome collaborators and the support of a great university.”

While much of Westerhoff’s work has focused on the risks nanomaterials can pose to contaminating rivers, lakes, streams and water treatment and delivery systems, he and his team are now exploring ways scientists can use nanotechnology to safely solve previously intractable water problems. He will also examine how machine learning and artificial intelligence can be applied to water quality datasets to help resolve global water issues.

Throughout his career, Westerhoff has been a leading contributor in the fields of environmental engineering and contaminant science, earning support from the Water Research Foundation, U.S. Environmental Protection Agency and the National Science Foundation, among numerous others. He currently directs the EPA Center for the Life Cycle of Nanomaterials and serves as deputy director of the NSF Nanosystems Engineering Research Center for Nanotechnology-Enabled Water Treatment. NEWT is developing technologies to provide sustainable water treatment systems for drinking water and industrial wastewaters. 

Westerhoff also teaches in the School of Sustainable Engineering and the Built Environment, one of the six schools in the Fulton Schools of Engineering at ASU.  

“The Clarke Prize is recognition of the extraordinary impact of Paul’s work in advancing research on the science and technology of water quality and safety,” said Kyle Squires, dean of the Fulton Schools of Engineering. “He’s been instrumental in helping the Fulton Schools become a leader in the water research community and it’s extremely rewarding to see him regarded in such high esteem by his community of peers.” 

The Clarke Prize marks the latest achievement for Westerhoff, who has garnered wide recognition for his work related to the treatment and occurrence of emerging water contaminants. He is the recipient of the 2018 WEF Fair Distinguished Engineering Educator Medal, a 2018 Fellow of the International Water Association and winner of the 2017 Sustainable Nanotechnology Organization Achievement Award and the 2006 Water Research Foundation Paul L. Busch Award. 

Westerhoff is the 26th winner of the distinguished award. Among the list of Clarke Prize recipients is ASU Regents Professor of Environmental Engineering Bruce Rittmann, the first ever Clarke Prize laureate and winner of the 2018 Stockholm Water Prize

“Dr. Westerhoff’s innovations in interdisciplinary water research have touched on many aspects of water quality and have helped create a healthier drinking water supply,” NWRI Executive Director Kevin Hardy said. “His unanimous endorsement by the Clarke Prize Executive Committee is a testament to his contributions and his standing in the water community.” 

The NWRI is an independent industry institute that collaborates with water utilities, regulators and researchers to develop new, healthy sources of drinking water. Westerhoff will be recognized during an award ceremony on Oct. 19, 2019, in Orange County, California, where he will deliver the 2019 Clarke Prize Lecture.

Lanelle Strawder

Assistant director for marketing and communications, Ira A. Fulton Schools of Engineering


ASU study reveals how bacteria can beat immune systems

July 30, 2019

Humans and animals can develop resistance to harmful bacteria (pathogens) over time or with help from antibiotics or vaccines. And it’s usually assumed that the pathogens will respond by multiplying even faster.

However, in a new study published this week in Proceedings of the National Academy of Science, researchers from Arizona State University, along with colleagues from the University of Exeter and Auburn University, show that the evolution of more severe infections is not necessarily driven by bacteria replicating quicker. House finch It's often thought that harmful bacteria will respond to resistance by multiplying faster. But in a new study of a bacterium that causes conjunctivitis in house finches, researchers now believe that a pathogen's virulence and ability to replicate evolve separately and may manipulate a host's immune system. Photo by Geoffrey E. Hill Download Full Image

The authors believe that once resistance spreads in host species, the bacteria’s virulence and replication rate can evolve separately, and virulence may be driven by other means, such as by manipulating host immune systems.

The research examined the spread of a bacterium called Mycoplasma gallisepticum (MG) among house finches — a common bird found at birdfeeders across the country. MG is a rare example of a well-studied, host-bacteria co-evolutionary race, where humans have not intervened with antibiotics or vaccines.

For more than two decades, ASU School of Life Sciences Professor Kevin McGraw has been studying diseases of finches. The researchers in this study discovered that strains of MG responded to resistance not by increasing in number but by increasing in strength and effectiveness of infection.

“Few have experimentally studied how the varied infection strategies of pathogens change over evolutionary time, so we weren’t sure what we would uncover in this system,” McGraw said. “Many have assumed previously that virulence and replication track one another as ‘full-court-press’ strategies for pathogen infection, but instead we found that one of them was prioritized over the other in the course of the evolutionary host-pathogen race.”

MG is a chronic respiratory illness that causes conjunctivitis — the infected bird’s eyes crust over and swell up, often closing completely. The sick birds can recover from the illness — if they do not first starve or fall victim to an unseen predator. The MG bacterium has been infecting house finches since the early 1990s when the disease spread rapidly and wiped out more than half of the U.S. East Coast house finch population. Within a decade, it had spread to parts of the West Coast.

However, after the initial crisis, the population stabilized. House finches began to develop resistance. But the disease has not disappeared.

House finch with severe symptoms of conjunctivitis.

House finch with severe symptoms of conjunctivitis. Photo by Geoff Hill, Auburn University

“We typically assume that pathogens respond to host resistance, including to vaccines, by increasing their rate of replication, allowing them to transmit faster to other hosts before they are cleared by their current host,” said Associate Professor Camille Bonneaud, with the University of Exeter. “However, our study shows that pathogens can evolve to become more virulent without increasing their rate of replication. We hypothesize that the increase in virulence that we observed in this study was driven by an improved ability of the pathogen to manipulate the host immune system in order to generate the symptoms necessary for its transmission.”

To understand how MG was responding to this resistance, McGraw and his colleagues tested both MG strains from early infections, before house finches were resistant, and newer strains. They found that rather than increasing their numbers, MG has found ways to be more efficient. Scientists have long predicted that a virus would use both strategies, rather than only one. 

Understanding the interactions between harmful bacteria and their hosts can help scientists develop new treatments for bacterial infections. 

“The results show us how we might design optimal treatments against a bacterial pathogen that has long encountered some form of resistance whether it be from the immune system of the natural host or an intervention like antibiotic use,” McGraw said. “In the case of a fight against MG, trying to knock back pathogen replication rate would not seem like the wise choice compared to targeting pathogen cell virulence.”

Melinda Weaver

Communications specialist, School of Life Sciences