Scientists are studying sewer water — to find out how many people have coronavirus

Researchers at Stanford University are studying sewer water to track coronavirus before people can be tested in cities, media outlets reported.

Scientists have collected samples from the San Francisco Bay Area’s treatment plants to learn more about how much COVID-19 spread in the region, Wired reported. Studies have shown there are high levels of viral shedding in feces in coronavirus patients, according to Wired.

Researchers at the KWR Water Research Institute in the Netherlands first reported that coronavirus can be found in sewer water samples, according to Wired.

Gertjan Medema, a microbiologist at KWR Water Research Institute, said analyzing sewer water can track coronavirus for people who have no symptoms or mild symptoms, according to Nature.

“Health authorities are only seeing the tip of the iceberg,” Medema said, according to Nature.

Around 25% of Americans are asymptomatic carriers of coronavirus, according to CDC Director Dr. Robert Redfield, ABC News reported.

Analyzing sewer water was also used in 2013 during the polio outbreak in Israel, according to ABC News. It allowed for polio vaccination in order to prevent an epidemic.

This story was originally published April 7, 2020 at 11:05 AM with the headline "Scientists are studying sewer water — to find out how many people have coronavirus."