Experts worry about how the United States will see the next COVID surge come

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NEW YORK (AP) — As coronavirus infections surge in parts of the world, experts are watching for a potential new outbreak of COVID-19 in the United States — and wondering how long it will take to detect them.

Despite improvements in disease surveillance over the past two years, they say, some recent developments do not bode well:

—As more people take rapid home COVID-19 tests, fewer people are getting the benchmark tests the government relies on for case numbers.

—The Centers for Disease Control and Prevention will soon use fewer labs to research new variants.

“Health officials are increasingly focused on hospital admissions, which only increase after a flare-up arrives.

—A wastewater monitoring program remains a patchwork that cannot yet be relied upon for the data needed to understand future surges.

—White House officials say the government is running out of funds for vaccines, treatments and tests.

“We’re not in an ideal situation,” said Jennifer Nuzzo, a pandemic researcher at Brown University.

Scientists recognize that the widespread availability of vaccines and treatments puts the nation in a better place than when the pandemic began, and that surveillance has come a long way.

For example, scientists this week presented a 6-month-old program that tests international travelers flying through four US airports. Genetic testing of a sample on December 14 revealed a coronavirus variant – the descendant of omicron known as BA.2 – seven days earlier than any other detection reported in the United States

In other good news, cases, hospitalizations and deaths in the United States have been falling for weeks.

But it’s different elsewhere. The World Health Organization reported this week that the number of new coronavirus cases rose for two weeks in a row around the world, likely because COVID-19 prevention measures were halted in many countries and because BA.2 spreads more easily.

Some public health experts are unsure what this means for the United States

BA.2 accounts for a growing share of cases in the United States, the CDC said — more than a third nationally and more than half in the Northeast. Small increases in overall case rates were noted in New York and hospital admissions in New England.

Some of the northern US states with the highest BA.2 rates, however, have some of the lowest case rates, noted Katriona Shea of ​​Penn State University.

Dr. James Musser, an infectious disease specialist at Houston Methodist, called the nationwide case data on BA.2 “disordered.” He added, “What we really need is as much real-time data as possible…to inform decisions.”

Here’s what COVID-19 trackers are watching and what scientists worry about them.

TEST RESULTS

Counts of test results have been central to understanding the spread of the coronavirus from the start, but they have always been flawed.

Initially, only sick people were tested, meaning the case count missed people who had no symptoms or couldn’t get swabbed.

Home test kits became widely available last year and demand took off when the omicron wave hit. But many people who test at home don’t tell anyone the results. Health agencies aren’t trying to round them up either.

Mara Aspinall is the managing director of an Arizona-based consulting firm that tracks COVID-19 testing trends. She estimates that in January and February, around 8 to 9 million rapid home tests were performed each day on average, four to six times the number of PCR tests.

Nuzzo said: “The number of cases does not reflect reality as much as it once did.”

VARIANT HUNT

At the start of 2021, the United States was far behind other countries in the use of genetic tests to look for concerning viral mutations.

A year ago, the agency signed agreements with 10 major laboratories to carry out this genomic sequencing. The CDC will reduce this program to three labs over the next two months.

The weekly volume of streaks done under contracts was much higher during the omicron wave in December and January, when more people were getting tested, and has already fallen to around 35,000. By late spring, it will have fallen to 10,000, though CDC officials say the contracts allow the volume to increase to more than 20,000 if needed.

The agency also says that turnaround times and quality standards have been improved in new contracts, and that it doesn’t expect the change to hurt its ability to come up with new variants.

Outside experts have expressed concern.

“It’s really quite a substantial reduction in our baseline surveillance and intelligence system to track what’s out there,” said Bronwyn MacInnis, director of genomic pathogen surveillance at the Broad Institute of MIT and Harvard.

WASTEWATER MONITORING

An evolving surveillance system looks for signs of coronavirus in sewage, which could potentially catch brewing infections.

The researchers linked the sewage samples to the number of positive COVID-19 tests a week later, suggesting that health officials could gain early insight into infection trends.

Some health departments have also used sewage to research variants. New York City, for example, detected signals of the omicron variant in a sample taken on November 21 – about 10 days before the first case was reported in the United States.

But experts note that the system does not cover the whole country. It also does not distinguish who is infected.

“It’s a really important and promising strategy, no doubt. But the ultimate value probably hasn’t been understood yet,” said Seattle/King County, Washington health officer Dr. Jeff Duchin.

HOSPITAL DATA

Last month, the CDC introduced a new set of measures for deciding whether to lift mask-wearing rules, focusing less on positive test results and more on hospitals.

Hospital admissions are a lagging indicator, as a week or more can elapse between infection and hospitalization. But a number of researchers think the change is appropriate. They say hospital data is more reliable and easier to interpret than case counts.

The lag is also not as long as one might think. Some studies have suggested that many people are waiting to get tested. And when they finally do, the results aren’t always immediate.

Spencer Fox, a University of Texas data scientist who is part of a group that uses hospital and cellphone data to predict COVID-19 for Austin, said “hospital admissions were the best signal” for an increase than the test results.

There are, however, concerns about future hospital data.

If the federal government lifts its public health emergency declaration, officials will lose the ability to compel hospitals to report COVID-19 data, a group of former CDC directors wrote recently. They urged Congress to pass legislation that will provide enduring authorities “so we don’t risk flying blind as health threats emerge.”

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AP reporters Lauran Neergaard in Washington and Laura Ungar in Louisville, Ky., contributed.

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The Associated Press Health and Science Department is supported by the Howard Hughes Medical Institute Department of Science Education. The AP is solely responsible for all content.

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