Government scientists on Tuesday confirmed that there has been an increase in the presence of Covid-19 in wastewater samples across the United States
The potentially worrying trend comes as the country casts masks and eases pandemic restrictions aimed at stopping the spread of a virus that in two years has killed nearly a million people in USA.
The Federal Centers for Disease Control and Prevention recognized the increase after Bloomberg reported that one-third of the agency’s wastewater testing sites showed an increase in Covid cases from March 1 to March 10.
That was double what it was from Feb. 1 to Feb. 10, when the highly contagious omicron variant that had roared across the country during the holiday season began to decline, the Bloomberg analysis of CDC data found.
“While wastewater levels are generally very low across the board, we are seeing an increase in the number of sites reporting an increase,” said Amy Kirby, head of the CDC’s wastewater monitoring program, in a statement. “These bumps may simply reflect a slight increase from very low levels to still low levels.”
Still, Kirby said, “Some communities may begin to see an increase in Covid-19 infections, however, as prevention strategies in many states have changed in recent weeks.”
The CDC’s test program is limited to areas that collect and report on wastewater monitoring and does not provide a national representation of Covid proliferation, the agency said.
So it’s still unclear if this is an ominous sign of things to come.
“It is too early to know whether this current trend will continue or whether we will see a similar increase in reported cases across the country,” Kirby said.
But Dr. Sadiya Khan, an epidemiologist at Northwestern University Feinberg School of Medicine, said the latest findings are cause for “serious concern.”
“This increase is not a surprise and is of great concern given the easing of restrictions on activities and masking in schools and communities,” Khan said in an email. “If you look at patterns in Europe, there has also been an increase in the last few days. “If we have learned anything in this pandemic, it is that the trends in Europe take precedence over our own.”
Khan said we have the tools to deal with any new Covid outbreak.
“The reaction should not be alarming, but should focus on the things that work: masking and vaccines / boosting,” Khan said. “I’m not giving up my mask for now.”
Cynthia Gibas, who heads the wastewater monitoring program at the University of North Carolina at Charlotte, agreed.
“We should not panic about this, but we should watch it very carefully over the next few days,” Gibas told NBC News.
Wastewater can show the presence of Covid-19 about a week before PCR testing can. People who have been infected throw the virus in sewage pipes for several days before showing symptoms, which triggered a Covid-19 test.
But wastewater is not the only metric that could indicate a possible resurgence in Covid cases.
“Even if more people suddenly start feeling the need to be tested, it’s an indication that something might be happening,” Gibas said.
The public health experts weighed in as The White House warned that the United States will soon run out of funding for the future Covid booster shots, new treatments and test efforts if spending legislation remains deadlocked Congress.
At the same time, as a sign of returning to normalcy, the Biden administration also announced that public tours of the White House will resume for the first time in two years on Friday and Saturday, starting April 15.
Currently, just over 75 percent of the U.S. population has received at least one vaccination against Covid-19, according to the CDC.
The unvaccinated continue to account for most of the reported Covid-19 deaths, according to analysis by the CDC and Kaiser Family Foundation.