At the beginning of the testing period, Honolulu reached its highest peak of more than 300 COVID-19 cases on a single day. After tougher COVID-19 restrictions were implemented, cases dropped to a seven-day average of 75 cases at the beginning of October 2020, when the sampling process concluded. Yan said the reduced concentration of the virus in the wastewater samples directly correlated with the drop in COVID-19 cases.
“Typically we think wastewater is loaded with enteric pathogens (microbes such as viruses, bacteria and parasites that cause intestinal illness). This study shows that wastewater surveillance can also be used to track community disease burdens of pathogens causing respiratory infections,” Yan said. “This is extremely important as we closely monitor emerging variants of COVID-19 in the community and other potential pandemic strains in the future.”