RESEARCH & INNOVATION
130 robots covering 350 campus buildings gradually suction sewage into collection bottles , providing a sample representative of a 24-hour period .
The team adds magnetic nanoparticles , designed to bind to any viruses in the samples .
Teams of students and staff collect the samples every morning and bring them to the lab of Professor Rob Knight .
THE SEWAGE SO
THROUGHOUT THE PANDEMIC , early detection and testing has been crucial to stemming the transmission of COVID-19 . So when evidence emerged that people infected with COVID-19 — with or without symptoms — shed the virus in their stool , UC San Diego researchers saw an opportunity for a novel early warning system . “ The sewer seemed like the ‘ happening ’ place to look for it ,” says Smruthi Karthikeyan , PhD , an environmental engineer and postdoctoral researcher who works in the lab of Rob Knight , PhD , at the School of Medicine .
Researchers in Knight ’ s lab are used to getting their hands dirty . The team has long studied the gut microbiome — unique communities of microbes that live in our gastrointestinal tracts . People all over the world participate in their research program , The Microsetta Initiative ( aptly abbreviated “ TMI ”), by mailing fecal samples to Knight ’ s lab . The crowdsourced project has allowed the team to study many factors that might influence the makeup of a person ’ s gut microbiome and the many ways the microbiome influences our health .
By the summer of 2020 , Karthikeyan , Knight and team were analyzing fecal samples closer to home — sewage flushed away by people in UC San Diego buildings — to look for the virus that causes COVID-19 . One month after the system went online , the team detected a positive case on a then sparsely populated campus .
“ At the time , we had just three wastewater samplers around campus , two by the hospital , which of course will be positive due to the patients being treated there , and one negative control by Revelle College ,” Karthikeyan says . “ I had packed up to leave the lab for the day when I saw that the Revelle sample was actually positive ! That launched a thousand ships and put the whole surveillance team on overdrive .”
The campus community was notified within 14 hours , with targeted messages sent to people associated with the affected buildings , recommending that they be tested for the virus as soon
12 TRITON | WINTER 2022