{"id":1130,"date":"2020-09-14T12:21:40","date_gmt":"2020-09-14T19:21:40","guid":{"rendered":"https:\/\/knightlab.ucsd.edu\/wordpress\/?p=1130"},"modified":"2025-08-01T11:06:32","modified_gmt":"2025-08-01T18:06:32","slug":"a-new-kind-of-college-exam-ucsd-is-testing-sewage-for-covid-19","status":"publish","type":"post","link":"https:\/\/knightlab.ucsd.edu\/?p=1130","title":{"rendered":"A New Kind of College Exam: UCSD Is Testing Sewage for COVID-19"},"content":{"rendered":"

Turds tell tales, and UC San Diego is listening.<\/a><\/span><\/span><\/p>\n

As the beginning of the school year nears, the university is preparing to ramp up its testing of sewage for the coronavirus. The goal: Monitor the progress of the pandemic on campus and catch outbreaks before it\u2019s too late to control them. Along those lines, UCSD on Saturday sent out its first campus-wide email alert about the detection of the virus in sewage from one of its seven colleges.<\/span><\/p>\n

Poop \u2014 and urine and other bodily fluids \u2014 are at the center of the effort since the human body secretes the coronavirus that causes COVID-19. Sewage analysis tests are sophisticated enough to detect one infected person out of 100,000 who are flushing toilets and taking showers, said virologist Charles Gerba of the University of Arizona, who\u2019s been working on a project to test Tucson-area sewage for the virus.<\/span><\/p>\n

\u201cYou can survey an entire community, can get an idea of the number of infected people, and see whether trends are going up or down,\u201d Gerba said. And, he said, the tests can act as an early warning system by alerting officials that people in a community like a dorm are infected a week before they might become sick enough to seek tests on their own.<\/span><\/p>\n

UCSD has been testing sewage for more than a month from two clinics, a research building and a dorm, said microbiologist Rob Knight, director of the Center for Microbiome Innovation. (Several thousand students have lived in UCSD dorms over the summer, including many from other countries who remain on campus over the break.)<\/span><\/p>\n

Knight said a researcher tests UCSD wastewater samples each day. \u201cSo far, we have seen the coronavirus only in the samples from buildings in which we know COVID-19 patients are housed,\u201d Knight said prior to Saturday\u2019s email alert, which let students and staff know that the virus had been found in wastewater from the Revelle College campus. The virus apparently came from someone who used a restroom there from 6 a.m. and 9:30 a.m. on Sept. 2. The email said: \u201cThousands of people are on the UC San Diego campus every day, including members of the public. This test is an early indication that one of them is shedding the virus, viral shedding starts before symptoms develop.\u201d<\/span><\/p>\n

Cases of virus detection may rise as a smaller-than-normal contingent of about 11,000 UCSD students returns to live on campus this month before the fall quarter begins on Sept. 28. The university is embracing<\/a> a mix of many online courses and a smaller number \u2013 about 12 percent of the total \u2013 of in-person classes.<\/span><\/p>\n

UCSD and the University of Arizona have plenty of company on the poop patrol front. According to the Washington Post, researchers are testing sewage<\/a> at colleges across the country for signs of the coronavirus. (This isn\u2019t a new idea: Scientists have tested sewage for signs of illness such as polio for decades.) \u00a0Locally, San Diego State University \u2013 home to an intense outbreak<\/a> \u2013 is not testing its sewage, a spokesman said. The University of Arizona, meanwhile, has tested sewage<\/a> from the municipal San Diego wastewater system.<\/span><\/p>\n

The key to testing is the viral RNA of the novel coronavirus \u2013 its genetic code. The human body sheds bits of the virus in poop and pee (\u201cso much for the myth that urine is sterile,\u201d the University of Arizona\u2019s Gerba said) plus blood and potentially other bodily fluids too.<\/span><\/p>\n

Poop from infected people includes about 1 million bits of virus per gram, he said.<\/span><\/p>\n

Sewage tests seek out those virus particles by searching for specific genes. If they find virus particles, researchers amplify them to figure out how many there are \u2013 a rough guide to how many people are infected among those who contributed feces and bodily fluids to the sewage sample.<\/span><\/p>\n

\u201cWe\u2019re taking a sample and using it to extrapolate to something larger,\u201d said microbiologist Marc Johnson of the University of Missouri. He\u2019s helping to spearhead a project to test public wastewater in the St. Louis area.<\/span><\/p>\n

\u201cFor wastewater testing, it doesn\u2019t matter how much clinical testing is offered, it doesn\u2019t matter how old the patients are, it doesn\u2019t matter if they are symptomatic or not, it doesn\u2019t matter if they have health insurance, it doesn\u2019t even matter if they believe in the virus,\u201d he said. \u201cAs long as they aren\u2019t pooping in a bucket, we can detect their infection.\u201d<\/span><\/p>\n

Sewage testing has already revealed two small COVID-19 outbreaks at the University of Arizona. First, in August, testing revealed signs of the virus in sewage from a dorm with 310 residents, Gerba said. \u201cWe estimated by the concentration that two to five people were infected. The next morning, they tested all the students, found three who were infected and removed them from the dorm. Then the sewage went negative.\u201d<\/span><\/p>\n

None of the infected students had symptoms.<\/span><\/p>\n

Later, testing revealed signs of the virus in two dorms where 29 students ultimately tested positive and were removed, Gerba said. \u201cIt seems to be working fairly well. We\u2019re hoping that it prevents major outbreaks.\u201d<\/span><\/p>\n

The sewage tests each cost $250 to a few hundred dollars and take about eight hours, researchers said. In Missouri, the sewage samples are small, only about a quarter-cup, and they don\u2019t stink because researchers \u201cfilter out all the solids,\u201d said Johnson, delicately.<\/span><\/p>\n

At UCSD, researchers are planning to dramatically expand the sewage testing program as students return to campus, said microbiologist Knight. The university is now offering free COVID-19 testing<\/a> to employees and to students who come to campus, and it hopes to launch a regular testing program for asymptomatic students and staff by October.<\/span><\/p>\n

As of Sept. 1, the campus reported<\/a> 43 positive COVID-19 cases among students out of 4,588 tests and 24 positive cases among campus employees out of 3,462 tests.<\/span><\/p>\n","protected":false},"excerpt":{"rendered":"

Turds tell tales, and UC San Diego is listening. As the beginning of the school year nears, the university is preparing to ramp up its testing of sewage for the<\/p>\n","protected":false},"author":1,"featured_media":1131,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[],"class_list":["post-1130","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-news"],"_links":{"self":[{"href":"https:\/\/knightlab.ucsd.edu\/index.php?rest_route=\/wp\/v2\/posts\/1130","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/knightlab.ucsd.edu\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/knightlab.ucsd.edu\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/knightlab.ucsd.edu\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/knightlab.ucsd.edu\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1130"}],"version-history":[{"count":3,"href":"https:\/\/knightlab.ucsd.edu\/index.php?rest_route=\/wp\/v2\/posts\/1130\/revisions"}],"predecessor-version":[{"id":1575,"href":"https:\/\/knightlab.ucsd.edu\/index.php?rest_route=\/wp\/v2\/posts\/1130\/revisions\/1575"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/knightlab.ucsd.edu\/index.php?rest_route=\/wp\/v2\/media\/1131"}],"wp:attachment":[{"href":"https:\/\/knightlab.ucsd.edu\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1130"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/knightlab.ucsd.edu\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1130"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/knightlab.ucsd.edu\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1130"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}