When someone has the coronavirus, some of it is shed in their fecal matter. So what people flush has become useful material to University of Washington researchers who are developing a new testing method for COVID-19 in sewage. The team is looking at wastewater that flows from people’s homes, sampling it at manholes and neighborhood pump stations before it goes to sewage treatment plants.
By collecting these specific wastewater samples, the researchers can identify and monitor infections on a community level with one test. It’s an efficient way to find positive cases in a neighborhood, without taking the time and money involved in regularly testing many individual people.
This method also accounts for asymptomatic people and reaches vulnerable populations that have less access to health care and individual testing, while still protecting people’s privacy. It could help track how COVID-19 vaccines are working now, and it might be an important tool when the pandemic is largely under control because it could help detect isolated cases early.
To detect COVID-19 infection levels from a sample, the researchers measure the amount of viral RNA and then compare that to the amount of molecules usually present in human waste. From there, the team can determine an approximate percentage of people with the virus.
Right now, the researchers are still testing this method, but if it is adopted, it will be the first time this type of system is implemented in Seattle.
Read more about this research here.