CDC: ‘Uptick’ in wastewater sites reporting increase in SARS-CoV-2 levels
Click Here to Manage Email Alerts
The CDC’s wastewater surveillance tracker shows that 165 U.S. sites have experienced an increase in SARS-CoV-2 levels in the last 15 days.
The 165 sites make up less than half of the 419 sites currently reporting data and “may simply reflect minor increases from very low levels to still low levels,” a CDC spokeswoman said.
“Currently, more than half of all sites reporting wastewater data are experiencing a decrease in SARS-CoV-2 levels. While wastewater levels are generally very low across the board, we are seeing an uptick of sites reporting an increase in their levels,” Kristen Nordlund told Healio.
“Some communities may be starting to see an increase in COVID-19 infections, as prevention strategies in many states have changed in recent weeks,” Nordlund said.
Since the CDC announced a new formula for assessing the need for masks, 49 of 50 states no longer require them to enter indoor facilities. Hawaii will end the nation’s only remaining statewide mask mandate on March 26.
Nordlund said it is too early to tell whether the wastewater trend will continue or there will be a corresponding increase in cases.
“It was always inevitable that, over time, cases would again rise in certain areas,” Amesh A. Adalja, MD, senior scholar at Johns Hopkins Center for Health Security, told Healio. “There was never a trajectory to zero. It’s unclear to what level cases will rise.”
The CDC’s wastewater tracker does not show which strains of SARS-CoV-2 are being detected. According to the CDC’s variant tracker, the proportion of U.S. cases caused by the omicron subvariant BA.2 has increased to more than 23%. The subvariant “appears to be more transmissible,” said Adalja.
“There is no evidence that the symptoms differ from other subtypes of omicron. But it is not surprising to see it behind an increase in cases,” he said.
“I do not think any variant will be able to erase all the protection immunity, monoclonals, and antivirals give us,” Adalja said. “Cases may increase, but that’s not so concerning, if they are largely outpatient. There needs to be a focus away from all cases to severe cases and hospitalizations. Normalcy, at this stage, is more a function of individual risk tolerance than anything the virus does.”
The CDC encourages local health departments to monitor the wastewater data closely and use them as a warning sign if levels continue to increase, Nordlund said.
References:
CDC. SARS-CoV-2 RNA levels in wastewater in the United States. https://covid.cdc.gov/covid-data-tracker/#wastewater-surveillance. Accessed March 16, 2022.
CDC. Variant proportions. https://covid.cdc.gov/covid-data-tracker/#variant-proportions. Accessed March 16, 2022.
Collapse
CDC. SARS-CoV-2 RNA levels in wastewater in the United States. https://covid.cdc.gov/covid-data-tracker/#wastewater-surveillance. Accessed March 16, 2022.
Read more about
Click Here to Manage Email Alerts