How big is the latest U.S. COVID wave? No one really knows.

Eileen Wassermann struggles to calculate her daily risks at this stage of the coronavirus pandemic—with infections drastically undercounted and mask mandates gone.

The immunocompromised 69-year-old ensconces herself in her SUV for the half-hour ferry ride across the Puget Sound from her home on Bainbridge Island to Seattle, where she undergoes treatment for the rare inflammatory condition sarcoidosis.

A retired scientist and lawyer who worked with drug companies, Wassermann is comfortable analyzing coronavirus data. But she said current numbers, which don’t account for most at-home test results, are unreliable.

“My mode, which sounds ridiculous maybe at this point, is to be as cautious as I was at beginning in 2020,” said Wassermann, who has received two booster doses of the coronavirus vaccine. “I don’t want to always walk around like a scaredy cat, but then on the other hand with this immune condition I have, I don’t want to take any chances.”

Americans like Wassermann are navigating murky waters in the latest wave of the pandemic, with highly transmissible subvariants of omicron spreading as governments drop measures to contain the virus and reveal less data about infections. With public health authorities shifting their focus to COVID-related hospitalizations as the pandemic’s U.S. death toll hits 1 million, people are largely on their own to gauge risk amid what could be a stealth surge.

Experts say Americans can assume infections in their communities are five to ten times higher than official counts.

“Any sort of look at the metrics on either a local, state or national level is a severe undercount,” said Jessica Malaty Rivera, an epidemiologist at the Pandemic Prevention Institute housed at The Rockefeller Foundation. “Everyone knows someone getting COVID now.”

Hospitalizations nationally have increased 50% since bottoming out six weeks ago. But the roughly 23,000 patients with COVID in hospitals over the last week still represent near the lowest hospitalization levels of the entire pandemic. The recent increase is driven by the Northeast, where hospitalization rates are almost twice as high as any other region.

Reported cases of COVID have also tripled in the Northeast in just over a month, driving much of the growth nationally, according to the Centers for Disease Control and Prevention. The country has averaged nearly 90,000 new cases each day over the past week—three times higher than the lowest point in March.

The latest uptick in infections is testing a new CDC alert system adopted by many local and state governments that categorizes COVID-19 community levels as “low” even with the number of new cases rising to a level once considered high.

More than two-thirds of Americans live in low-risk areas under these metrics. But 43% of residents in the Northeast live in areas considered high risk, compared to 9% of the Midwest and less than 1% each in the South and West.

“If there’s one word to sum up where we are, it’s ‘unpredictable’,” said Jeffrey S. Duchin, the top public health official in Seattle and King County, where cases have climbed significantly in recent weeks after falling off following the omicron wave.

“Things are clearly better than they were in the past,” Duchin said. “Vaccines are doing a great job at keeping people out of the hospital, but the virus is becoming more transmissible.”

Experts say the rise in infections is not surprising, especially after governors scrapped indoor mask mandates and a judge voided the federal mask requirement for public transportation. Spring is also a season for gatherings from Easter brunch to proms and graduations.

“It’s the next phase of the return to normal: Every time we take that next big step, there’s always a rebound,” said David Rubin, who tracks national coronavirus trends for the PolicyLab at the Children’s Hospital of Philadelphia. “If you are at risk, you should exercise caution and certainly consider masking in public places.”

Public health authorities are not as worried about rising cases because the infected are increasingly vaccinated and boosted and have access to therapeutics such as the antiviral Paxlovid that help prevent people from becoming seriously ill.

But doctors say the new CDC public reporting categories obscure the true risk of contracting COVID-19, which still disrupts lives, can lead to long-term complications, and poses heightened danger for the elderly and immunocompromised.

“It allows people to move around and to have a false sense of security,” said Jayne Morgan, executive director of the COVID task force at Piedmont Healthcare in Georgia.

“It’s concerning in a public health crisis we have moved away from practicing prevention,” Morgan added. “The best medical physicians always practice preventive health care. It’s why you get mammograms. It’s why you get colonoscopies. You don’t wait for the cancer to develop.”

The District of Columbia is among the communities where tensions are brewing as residents question the official designation of low community risk.

Local health officials stopped publicizing daily cases on their website after the omicron wave, telling residents to treat coronavirus more like an endemic illness and less like an emergency. In recent weeks, the city also stopped reporting results from wastewater virus monitoring and providing daily data to the CDC, leaving people with little information as infections rise.

The Institute for Health Metrics and Evaluation estimates only about 13% of cases are being detected. But the organization’s director Christopher Murray says the United States is still in good shape and not on track to experience a surge of omicron subvariants seen in the United Kingdom.

“We have very, very low ICU admissions. We have really low deaths. And we probably have very high levels of immunity because omicron has infected so many people, vaccination is moderately high and a number of people are being boosted,” Murray said. “We are in a good state and we will stay in that way until the fall and winter when immunity has waned a lot or until some nasty new variant shows up.”

John Brownstein, chief innovation officer at Boston Children’s Hospital, said New England is experiencing a hidden COVID wave based on survey data suggesting five positive at-home coronavirus tests for every two lab tests. But that has not led to a worrying spike in hospitalizations.

New York state has recorded one of the nation’s highest COVID-19 hospitalization levels at 14 of every 100,000 residents as of Monday, according to The Washington Post tracker. But hospitals say this is skewed by patients admitted for other reasons, then testing positive for the coronavirus.

Mangala Narasimhan, chief of critical care services at Northwell Health, New York’s largest health network, said patients with COVID are not coming in with pneumonia and struggling to breathe as they had been the last two years.

“A lot of people I know in the community have COVID,” she said. “None of that is being reflected here in the hospitals.”

Delaware and Maine are seeing the nation’s highest per capita hospitalization rate at 18 per 100,000 residents. But hospital associations in both states say their situations are manageable. In Delaware, the 111 patients hospitalized as of last Thursday is far below the 759 peak in January that prompted hospitals to declare a crisis that allowed them to ration care.

Watching reports of rising cases in the Northeast, Josh Elliott is uneasy about returning to once regular pleasures such as attending concerts and dining indoors in his Atlanta suburb.

Elliott is extra cautious because asthma and lung damage from pneumonia places him at a higher risk for severe COVID-19 disease. He worries about a hidden surge since Georgia now reports cases weekly instead of daily.

With reliable data, Elliott said he would feel more comfortable attending a friend’s upcoming wedding and celebrating his upcoming 30th birthday at a restaurant with his girlfriend—instead of eating takeout.

“I want to have a nice birthday meal and not bring it home and get COVID for my birthday,” he said.