Covid cases in the US may have already peaked just weeks into the latest upswing in infections, data suggests.
Scientists tracking the virus’ spread by testing sewage nationwide say the number of samples coming back positive has dropped 5 percent in the past week.
Dr Cristin Young, an epidemiologist involved in the wastewater surveillance project, said: ‘All fingers crossed this wave is plateauing and may be declining.’
If true, it would bring an end to several months of rising infection levels – spurred on by two highly infectious new variants, Eris, or EG.5, and Pirola, or BA.2.86.
The sharp uptick – which never translated into a big rise in deaths or ICU admissions – spooked many hospitals, schools, and businesses into requiring masks again.
Americans wear face masks as they wait in line to vote in the 2020 presidential election. Some colleges and businesses are reinstating mask mandates as Covid cases rise in the US
Scientists tracking the virus’ spread by testing sewage nationwide say the number of samples coming back positive has dropped 5 percent in the past week (shown)
The decline was driven by dips in positive samples in mid-Atlantic states like Virginia and Maryland . Collection sites in the Midwest and Northeast, on the other hand, show a steady increase in Covid spread
Dr Young and his team at Biobot Analytics are using the wastewater from 257 sites across the country to track the spread of the virus – a technique pioneered during the pandemic.
Their results show that in the week to September 13, daily new Covid cases were estimated to be at around 60,000, down around 5 percent in a week.
Collection sites in the Midwest and Northeast, on the other hand, show a steady increase in Covid spread.
Biobot’s findings are backed up from surveillance in North Carolina, said Jessica Schlueter, an associate professor in the department of bioinformatics and genomics at the University of North Carolina Charlotte.
She is responsible for testing wastewater at a dozen sites in her state.
The increase in Covid wastewater samples during the last six months ‘seems to be peaking and starting to taper off,’ she said, which could spell a fall in cases.
Official data shows the rate of increase in Covid hospitalizations has also slowed, after they rose by 7.7 percent over the most recent week that data is available — marking the slowest uptick since early July when hospitalizations were at a record low.
Latest data shows there were 20,538 Covid admissions to US hospitals in the week to September 9.
There are also signs that Covid deaths are beginning to level off.
A total of 844 were recorded in the week to August 19, the latest available. Data for the following week is incomplete, but it currently suggests 860 fatalities linked to the virus were recorded over this period — an increase of 1.8 percent.
But not everyone is so optimistic.
Dr Amy Kirby, head of the CDC’s wastewater monitoring program, told NBC News: ‘We have seen enough data over the years to know that around the time when school starts, we will start seeing some increases.’
These are expected to ‘plateau and then come back down’ before another winter surge, she warned.
Wastewater surveillance has ‘demonstrated benefit as a robust, highly adaptable platform for community-level surveillance for SARS-CoV-2 transmission,’ a report by the CDC said last week.
Weekly Covid hospitalizations are increasing, according to the latest CDC data
Deaths are starting to decrease again, but are rising from near historic lows
Now that testing for Covid has largely been scrapped, wastewater surveillance is one of the only ways officials are tracking the spread of the virus in the US.
In a pilot study during last year’s flu and RSV season, concentrations of the RSV and flu in wastewater samples from three major Wisconsin cities were collected and compared to the number of ER department visits related to the viruses in the area.
Flu and RSV are not universally tested for, so wastewater could be an important early warning sign.
Anybody infected with a virus sheds tiny fragments of its DNA in their poop.
Higher concentrations in sewage were linked to more ER department visits to do with flu and RSV.
Higher concentrations of the viruses in wastewater often preceded ER visits and indicated that a rise was on its way, the CDC said.
This could be used as an effective warning system for ER medical staff of a forthcoming outbreak in the area.
‘Hopefully with updated vaccinations, we will not see a big winter surge as we have in the past,’ Dr Kirby said. ‘But it’s really too early to tell.’