Presence of SARS-Coronavirus-2 in sewage

Gertjan Medema; Leo Heijnen; Goffe Elsinga; Ronald Italiaander; Anke Brouwer

In December 2019, an outbreak of coronavirus respiratory disease (called COVID-19) initiated in Wuhan, China. The outbreak was caused by a new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The outbreak spread from Wuhan to other cities in China and many other countries. WHO declared a pandemic on March 11, 2020 , when the disease was reported in 114 countries. 1 The primary mode of transmission is via respiratory droplets that people cough, sneeze or exhale, and may also be spread via fomites. 2 SARS-CoV-2 is 82% similar to SARS coronavirus that caused an outbreak in 2003. 16-73% of patients with SARS were reported to have diarrhea in addition to respiratory symptoms 3 , and transmission of SARS via water droplets from faeces via air ventilation systems in Amoy Gardens in Hong Kong was reported. 4 Diarrhea is also reported in a significant proportion of the COVID-19 cases and recent reports show that SARS-CoV-2 has been detected in stool samples of COVID-19 cases. [5] [6] [7] [8] [9] The shedding of SARS-CoV-2 was studied in a cluster of 9 cases and was 10 7 RNA copies/g faeces one week after symptom onset and decreased to 10 3 RNA copies/g three weeks after symptom onset. 10 In stool samples with high RNA copies, viable SARS-CoV-2 was detected. 11 Although it is unlikely that wastewater will become an important transmission pathway for coronaviruses like SARS-CoV-2 12 , increasing circulation of the virus in the population will increase the virus load into the sewer systems of our cities. It is important to collect information about the occurrence and fate of this new virus in sewage to understand if there is no risk to sewage workers, but also to determine if sewage surveillance 13 could be used to monitor the circulation of SARS-CoV-2 in our communities, that could complement current clinical surveillance, which is limited to the COVID-19 patients with the most severe symptoms. Sewage surveillance could also serve as early warning of (re-)emergence of COVID-19 in cities, much like the sewage surveillance for poliovirus that has been used for this purpose. 14 The objective of this investigation was to identify if SARS-CoV-2 is present in domestic wastewater of cities and a main airport during the early stages of the COVID-19 epidemic in the Netherlands.