Falling demand for COVID tests may leave U.S. exposed

WASHINGTON — Just five weeks ago, Los Angeles County was conducting more than 350,000 weekly coronavirus tests, including at a massive drive-thru site at Dodger Stadium, as health workers raced to contain the worst COVID-19 hotspot in the U.S.

Now, county officials say testing has nearly collapsed. More than 180 governmentsupported sites are operating at only a third of their capacity.

“It’s shocking how quickly we’ve gone from moving at 100 miles an hour to about 25,” said Dr. Clemens Hong, who leads the county’s testing operation.

After a year of struggling to boost testing, communities across the country are seeing plummeting demand, shuttering testing sites or even trying to return supplies.

The drop in screening comes at a significant moment in the outbreak: Experts are cautiously optimistic that COVID-19 is receding after killing more than 500,000 people in the U.S. but concerned that emerging variants could prolong the epidemic.

“Everyone is hopeful for rapid, widespread vaccinations, but I don’t think we’re at a point where we can drop our guard just yet,” said Hong. “We just don’t have enough people who are immune to rule out another surge.”

U.S. testing hit a peak on Jan. 15, when the country was averaging more than 2 million tests per day. Since then, the average number of daily tests has fallen more than 28 percent. The drop mirrors declines across all major virus measures since January, including new cases, hospitalizations and deaths.

Officials say those encouraging trends, together with harsh winter weather, the end of the holiday travel season, pandemic fatigue and a growing focus on vaccinations are sapping interest in testing.

“When you combine all those together you see this decrease,” said Dr. Richard Pescatore of the health department in Delaware, where daily testing has fallen more than 40 percent since the January peak. “People just aren’t going to go out to testing sites.”

But testing remains important for tracking and containing the outbreak.

L.A. County is opening more testing options near public transportation, schools and offices to make it more convenient. And officials in Santa Clara County are urging residents to “continue getting tested regularly,” highlighting new mobile testing buses and popup sites.

President Joe Biden has promised to revamp the nation’s testing system by investing billions more in supplies and government coordination. But with demand falling fast, the country may soon have a glut of unused supplies. The U.S. will be able to conduct nearly 1 billion monthly tests by June, according to projections from researchers at Arizona State University. That’s more than 25 times the country’s current rate of about 40 million tests reported per month.

With more than 150 million new vaccine doses due for delivery by late March, testing is likely to fall further as local governments shift staff and resources to giving shots.

“You have to pick your battles here,” said Dr. Jeffrey Engel of the Council of State and Territorial Epidemiologists. “Everyone would agree that if you have one public health nurse, you’re going to use that person for vaccination, not testing.”

Some experts say the country must double down on testing to avoid flare-ups from coronavirus variants that have taken hold in the U.K., South Africa and other places.

“We need to use testing to continue the downward trend,” said Dr. Jonathan Quick of the Rockefeller Foundation, which has been advising Biden officials. “We need to have it there to catch surges from the variants.”

Still, U.S. test manufacturers continue ramping up production, with another 110 million rapid and home-based tests expected to hit the market next month.

Government officials long assumed this growing arsenal of cheap, 15-minute tests would be used to regularly screen millions of students and teachers as in-person classes resume. But recent guidelines from the Centers for Disease Control and Prevention don’t emphasize testing, describing it as an “additional layer” of protection, behind basic measures like masking and social distancing.

drawdown at Candlewood Lake is almost done.

But the answer to the question on everyone’s mind — did it stop the lake’s nascent zebra mussel population in its tracks? — is still up on the air.

Divers, docks and mussel motels may answer it by fall. Now, it’s wait-and-see.

“It’s too early to tell,’’ said Neil Stalter, the Candlewood Lake authority’s director of ecology and environmental education.

Here’s what is known. Last year, people found 39 zebra mussels — small, striped, seemingly innocuous — along the lake’s shoreline.

Stalter said he’s confident that the winter’s deep drawdown — which lowered the lake’s level by 11 feet — exposed any other shoreline zebra mussels to air, killing off the non-native, profoundly invasive mollusks.

What no one knows is whether other mussels anchored themselves on rocks in deeper water, readying to infest the lake, with its thousands of offspring producing thousands more.

If that’s the case, look south to Lake Lillinonah.

In 2010, divers found exactly one zebra mussel in the lake. The ones the divers didn’t find did the damage.

“Within three years, they were everywhere,’’ said Greg Bollard, a member of Save the Lake, the nonprofit organization supporting environmental efforts at Lillinonah.

Shannon Young, chairman of the Lake Lillinonah Authority, said that now, the weight of zebra mussel encrustations make some docks too heavy to haul out of Lillinonah’s water to repair.

Bollard said some lake residents have now built lifts to raise their boats’ hulls out of the water, lest mussels begin to glom onto them after a few days sitting dockside.

Young said to avoid contaminating any other lake with the mussel-contaminated bilge, he sticks to boating on Lillinonah.

“I never use any other water body, period,’’ he said.

When zebra mussels multiply in sufficient numbers, they feed voraciously on plankton and algae. Filtering out all that organic matter leaves the water very clear.

That’s not a good thing. Bollard said the clear water lets sunlight penetrate deeper into a lake. That means invasive aquatic weeds like

Eurasian watermilfoil get extra sunlight and grow tall and thick — something that’s happening now at Lillinonah.

Watermilfoil is the other invasive species the drawdown at Candlewood Lake could knock back. The retreating water leaves the weeds exposed to winter’s frigid air, killing them.

But February’s heavy snows may have stymied that effort this year. The snow provides the watermilfoil with a nice insulating blanket, letting it survive until spring.

The snow also ended any attempt by volunteers to walk the lake’s 60 miles of shoreline, looking for zebra mussels on shoreline rocks and crevices.

“Clearly, the snow put the kibosh on that,’’ said Steve Kluge of New Milford, and a member of the Candlewood Lake Authority.

Now, Candlewood on the rise.

First Light Power Resources maintains the lake’s level via the Rocky River power plant in New Milford — it lets the lake’s waters flow down through the plant’s turbines in the fall to lower the lake, then pumps water from the river back up into the lake in the spring.

First Light spokesperson Len Greene said this year, the company dropped the lakes level from its working level of 429.5 feet above sea level to 418.5 feet. But it now has to return the lake to the working level by mid-April for the start of the fishing season.

“In the next month and a half, we’ll be pumping up quite a lot,’’ Greene said.

Full or drained, there is still hope Candlewood will be spared a zebra musselinfested future.

Because people found Candlewood’s 39 zebra musThe sels scattered in different spots along its shoreline, there’s the thought that the mussels aren’t concentrated in a clustered colony.

“There’s no pattern to Kluge said.

Stalter said 2020 water quality samples showed no evidence of zebra mussel veligers — the microscopic larval stage of the mollusks — swimming in the lake’s waters.

But there is this. Zebra mussels — natives to the Caspian and Black Seas — showed up the Great Lakes in 1988. In 32 years, they invaded waters as far south as Louisiana. They’re in all the Great Lakes, in Lake Champlain and the Hudson River.

And the Housatonic. Kluge said the zebra mussel threat shows the need for more scientific study — especially on how Candlewood’s waters move.

“It really highlights the need for further exploration of how Candlewood Lake works,’’ he said. it,’’