June 26, 2022

A group of student’s from Northeast Japan’s Tohoku University School of Engineering has announced to work on a project to predict the coronavirus’s spread by examining sewage.

The team amidst the rising concerns of a potential sixth infection wave is estimating the new case numbers for the coming week based on virus amounts in sewage. It further hopes that the local governments will use the information to secure adequate hospital bed numbers.

According to reports, the research group, led by Professor Daisuke Sano, since August 2020 has been investigating virus concentrations in waste water. The team collects samples twice weekly for analysis at a treatment plant from where about 70% of the city of Sendai’s sewage flows to.

The team findings –

• It found a strong correlation between detected virus amounts and new infection cases emerged from the third to fifth waves.
• The team built a computational model based on the data with machine learning to produce predictions for the next week’s new case numbers.
• It mentioned that the virus is detectable in sewage when one in 10,000 people is infected.
• The team’s latest forecast released Nov. 22 showed that around 25 new cases were expected between Nov. 22 and Nov. 28.

Professor Sano and other researchers mentioned that they have noticed links between norovirus concentrations in sewage water and norovirus patient numbers.

The team has been working with the Sendai Municipal Government to release data since 2017 on norovirus concentrations in waste water via a dedicated website. And since Nov. 8, it has emailed coronavirus prediction results to a mailing list with about 2,000 registered users so far.

According to the findings, these days, the actual new infection totals have tend to come in lower than the projections due to the progression of vaccinations and the spread of correct mask usage. While in the future, to improve its accuracy the actual data will be reflected in the calculation model.

Lastly, Sano mentioned that in countries such as South Korea and Germany, infections among older people have risen as the passage of time has reduced the effectiveness of their second vaccine shots.