Checking wastewater treatment plants for the poliovirus in sewage in 2013 helped Israeli epidemiologists monitor the outbreak that occurred in the country. With the welcome reduction in COVID-19 cases in the country, a group of Ben-Gurion University of the Negev (BGU) scientists in Beersheba have developed a new methodology to trace the SARS-CoV-2 virus that causes the disease through the sewage and wastewater systems.
They already determined in their first round of sampling that it passes through feces into the sewage. But no one is yet certain if the virus remains contagious in sewage. In addition, if their new methodology is added to the regular screening tests for sewage and wastewater, it could be used to determine the extent of the current outbreak and become an early warning system for future outbreaks.
The team, led by Prof. Ariel Kushmaro of BGU’s Avram and Stella Goldstein-Goren department of biotechnology, was joined in the project by Dr. Itay Bar-Or, a virologist from Sheba Medical Cente; Dr. Yakir Berchenko of BGU’s department of industrial engineering and management who was involved in the poliovirus monitoring; Dr. Oded Nir of the department of desalination and water treatment at BGU’s Zuckerberg Institute for Water Research; and Prof. Eran Freedler from the Technion-Israel Institute of Technology in Haia. They have already applied for grants to further the research.
After conducting sampling at large and small wastewater treatment plants in Israel and several additional spots in the sewage pipeline of Tel Aviv area during the coronavirus outbreak, the Beersheba team has confirmed SARS-CoV-2 RNA in sewage. They also found a larger concentration in the vicinity of Bnei Brak (which is populated almost solely by ultra-Orthodox Jews), which corresponds with an outbreak hot spot.
So they believe screening sewage and wastewater could give a better indication of the spread of the virus than current methods. The next question they are planning to answer is whether the virus is still infectious when it appears in sewage. Previous coronaviruses, like SARS, could survive in sewage for long periods only below 20 degrees Celsius.
Israel is the world’s leader in reusing water from sewage (mainly for agriculture), so it is especially crucial here to determine if the virus is being passed through feces or other routes into the sewage while remaining infectious. If it does remain infectious, sewage maintenance workers could be an additional vector for the spread of the virus. This is also relevant for poorer regions with worse sanitary conditions, where there is a higher risk of someone being exposed to untreated sewage.
Looking to the future, the team members believe that their new methodology could be incorporated as a standard screening test of sewage to provide early warning should another outbreak occur.
The project is under the auspices of BGU’s Coronavirus Task Force, which was created by BGU president Prof. Daniel Chamovitz to harness the ingenuity and research of the faculty and students to tackle the various aspects of the COVID-19 pandemic.