'A winter wave' of COVID could be coming as America gathers for the holidays

Along with holiday travel hazards and hassles comes another seasonal concern: a rise in the potential for COVID-19.

Evidence of COVID in the population is increasing across the nation – just as folks prepare to travel to and from holiday gatherings.

The finding comes from measurements of COVID virus found in the Centers for Disease Control and Prevention's National Wastewater Surveillance System. An increase in COVID virus activity in wastewater nationwide for the week ending Dec. 14 – having risen to a moderate level, up from a low level the week before – suggests an increased risk of infection, the CDC says.

More than 40% of the states (21) have high or very high levels of COVID virus in the wastewater, according to the CDC.

This shouldn't be a surprise and it's likely the CDC would find increased levels of pneumonia and respiratory syncytial virus, or RSV, in wastewater, too, said Noah Greenspan, program director of the Pulmonary Wellness & Rehabilitation Center in New York City.

But it comes at the time of year when "people may not as careful as they need to be to keep themselves safe," Greenspan told USA TODAY. "At a time when people are spending more time indoors, attending holiday events and gatherings, and there is an increase in circulating pathogens, people really need to take precautions if they don’t want to get sick."

Cold season tips:How to avoid catching COVID and flu during the holidays

CDC wastewater findings suggest 'winter wave' is coming

Based on previous COVID pandemic waves, the wastewater findings suggest the country is "heading into a large winter wave now," Michael Hoerger, a public health expert at Tulane University School of Medicine who tracks COVID-19 trends, said in a data presentation posted Dec. 16 on X.

He estimated that one in 64 in the U.S. are "actively infectious."

"So this is something to take very seriously."

Hoerger also posted a holiday forecast of potential COVID-19 exposure risks, including a one in eight chance of exposure in a family gathering of 10 people "if nobody is testing/isolating."

“This is a very risky time in terms of lots of people interacting indoors, so we don’t really know how quickly transmission can pick up,” Hoerger told Today.com.

The level of SARS-COV-2 (the virus that causes COVID-19) found in wastewater had fallen since this past summer, when nearly half of the United States have reported "very high" levels of COVID-19 activity. That came after a spring decline from "very high" levels of COVID virus activity this time last year.

By monitoring wastewater, researchers can detect how prevalent viruses are in a population, even "before people who are sick go to their doctor or hospital," according to the CDC, which created the system in 2020. "It can also detect infections without symptoms. If you see increased wastewater viral activity levels, it might indicate that there is a higher risk of infection."

Regions with highest levels of COVID in wastewater

Looking at the U.S. by region, COVID levels in wastewater increased in three regions (Midwest, Northeast and South) during the week ending Dec. 14. They declined slightly in the West from the week ending Dec. 7 to Dec. 14, according to the CDC. Only the Midwest region has increased to a high level:

• Midwest: Overall, the region registers as high, up from moderate. Missouri and South Dakota, registered very high levels of COVID virus in wastewater but those states had limited reporting coverage.
• Northeast: Remains at low, although New Hampshire registered as very high.
• South: Remains at low.
• West: The region fell slightly and remains at low, though  New Mexico registered as very high.

Knowing there's an increased prevalence of the COVID virus in wastewater is a sign to be vigilant. "These are things that, if we know they are on the rise, people can take actions like better hand washing, like immunization, like masking to prevent them," David Payne, lab director for the City of Milwaukee Health Department, told Fox 6 News earlier this week.

COVID test rate, hospitalization and deaths remain low

Other barometers of COVID activity have remained low, but that's why CDC began monitoring wastewater – to get an early warning of possible COVID-19 spread.

• Deaths: The percentage of deaths due to COVID-19 rose 1.1% for the week ending Dec. 14. The number of COVID-related deaths is down from this year's high of 2,583 for the week ending Jan. 13, 2024, to 254 in the week ending Dec. 14, the CDC says.
• Hospitalizations:Those related to COVID-19 have fallen from 10.7 per 100,000 in October to 2.3 per 100,000 so far in December, according to the agency.
• Tests:Weekly positive COVID-19 tests have risen slightly to 5.6% for the week ending Dec. 14 – higher than the 4.1% rate for the week ending Nov. 16 – but still far below 17.8% rate for the week ending Aug. 10.
• Emergencies: The percentage of emergency department visits diagnosed as COVID the week ending Dec. 14 amounted to 0.7%, almost the same as since mid-October.

Signs of flu in wastewater on the rise, too

Nationally, the amount of influenza A virus in the nation's wastewater has risen from low to moderate, over the week ending Dec. 14, according to the CDC.

COVID-19 and flu symptoms

Both illnesses have a spectrum of symptoms including no symptoms. Here are some common symptoms to COVID-19 and flu, according to the CDC:

• Fever or feeling feverish (Not everyone with flu will have a fever.)
• Chills
• Cough
• Shortness of breath or difficulty breathing
• Fatigue or tiredness
• Sore throat
• Runny or stuffy nose
• Muscle pain or body aches
• Headache
• Vomiting
• Diarrhea (more frequent in children with flu, but can occur in any age with COVID-19)
• Change in or loss of taste or smell – more frequent with COVID-19

The flu typically kicks in faster; a person may experience symptoms anywhere from one to four days after infection, according to the CDC. With COVID-19, a person may experience symptoms anywhere from two to five days, and up to 14 days after infection.

Those with the flu are potentially contagious for about one day before they start to show symptoms. But someone with COVID-19 may be contagious two to three days before their symptoms begin, with infectiousness peaking one day before they do.

Don't want to get sick this holiday season? Do this.

To decrease the likelihood of getting sick, Greenspan shared preventive measures you can take:

• Wash your hands frequently or use antibacterial gels, wipes or sprays.
• Get vaccinated.
• Wear a mask when in small or crowded spaces.
• Avoid touching your face or picking your nose.

And remember, "anything that is touched by many people, many times each day has a greater chance of being contaminated with bacteria, viruses, and other pathogens," he said.

Follow Mike Snider on X and Threads: @mikesnider & mikegsnider.

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