When Madeline Santiago decided to take her 12-year-old daughter on vacation to see relatives in Puerto Rico, she didn’t count on a stressful side trip into the surreal world of COVID-19 testing.

Puerto Rico now requires all visitors to prove they tested negative for infection no more than 72 hours before arriving in the U.S. island commonwealth — even though test processing in the United States is so backed up that getting results typically takes a week or two.

To ensure she’d have her results, Santiago got tested weeks before departing Philadelphia. But the 33-year-old health insurance salesperson couldn’t find any collection site in the region that would take a swab from her daughter for testing.

“I was completely ready for them to turn us back at the airport” in Puerto Rico, Santiago said Thursday, the day they arrived. “We went through a small screening and completed a declaration form that we were tested. But I have yet to receive my results” from testing giant LabCorp.

Barely three months have passed since the nation’s initial epic diagnostic testing failures. Now, despite ramping up testing, the U.S. is again bungling the use of this tool, so vital to controlling the pandemic.

This time around, the mishandling is not so much about shortages of swabs, protective gear, and test kits — although supply chain issues exist. Now, experts and labs say, the problem is the soaring numbers of cases in hot spot states in the South and West, combined with a fragmented lab system and lack of federal coordination.

As a result, people like Santiago have to wait so long for a test result that it loses its purpose. Meanwhile, hot spots are so swamped that testing is again being restricted to people with symptoms, even though the virus can be be spread before symptoms appear and by people who show no signs of illness.

Prompt testing and diagnosis are crucial, according to a statistical modeling study published Friday in the journal Lancet. If testing is delayed by three days or more after a person develops symptoms, then tracing close contacts so they can self-quarantine for two weeks will fail to reduce transmission of the virus. (Two weeks is enough time to be confident the person will not become ill and be contagious.)

Contact tracing will only work to curb the spread if infected people receive a positive test result on the same day they develop symptoms, concludes the analysis by Dutch and British researchers.

What good is an outdated test result?

In March, most states closed all but essential businesses and ordered people to stay home. The severe shutdowns were the only way to stop the explosion of cases and deaths following the federal government’s failure to act in the early weeks of the U.S. outbreak.

The national lockdown curbed the exponential increase, eased the burden on hospitals, and gave time for public health, hospital, and commercial labs to increase testing capacity. (New federal laws mandate testing with no out-of-pocket costs for patients.)

The U.S. is now testing an average of more than 675,000 people a day, a sixfold increase from early April, according to the COVID Tracking Project. Experts disagree about whether that’s enough, especially given the surge of cases in hot-spot states that rushed to reopen with few restrictions. But with beefed-up capacity, testing has expanded to people with no symptoms.

There are countless personal reasons a symptom-free person who has followed masking and social distancing precautions would still want a diagnostic test: to travel outside the country, visit a newborn grandchild, get a job or be allowed back to a job, allay anxiety.

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Michelle Fay Cortez, a Bloomberg News science reporter, wanted a negative test before visiting her parents because they have health problems that could make COVID-19 lethal. She gave a respiratory sample at a CVS drive-though site. A week later, she was told results might take 10 days.

“In the end, I will have to make a personal decision,” she wrote in an article published Thursday. “It will be a gamble. How badly do I want to see my parents, who are nearing their 80s, versus how dangerous might that visit be? I don’t know if I could live with myself if I brought the coronavirus to them.”

“This is atrocious,” tweeted Thomas Frieden, former commissioner of the U. S. Centers for Disease Control and Prevention. “What good is a test for Covid if it comes back after the patient’s infectious period? We are deluding ourselves if we think these tests are of much use. Rapid results are crucial.”

Cornering a market

These delays are not simply an issue of demand outstripping supply. Testing capacity at academic and other relatively small labs has gone begging because the biggest commercial players — notably Quest Diagnostics, LabCorp, BioReference Laboratories, and Sonic Healthcare — have practically cornered the COVID-19 testing market, the New York Times reported in May.

These big players have built their test-ordering procedure into electronic medical-record systems, and negotiated deals with nursing homes, health systems, insurers, drugstore chains — and state health departments.

“We know that we need to continue to ramp up our testing capacity, and are working to do that,” Pennsylvania health department spokesperson Nathan Wardle told The Inquirer in June. “We have partnered with a number of companies, such as Rite Aid, CVS, Walmart through Quest, to ensure testing is available to all Pennsylvanians.”

But this concentration has a downside. Quest and LabCorp — which process nearly 40% of the nation’s 675,000 daily tests — have both issued statements saying they can’t keep up.

“Despite our rapid scaling up of capacity, soaring demand for COVID-19 molecular diagnostic tests across the United States is slowing the time in which we can provide test results,” Quest said on Monday, pegging the time at seven days or more for most results.

“With significant increases in testing demand and constraints in supplies and equipment, the average time to deliver results may now be 4-6 days from specimen pickup,” LabCorp said on July 8.

Unlike in March, the backup is not because the molecular analysis — which hunts for a fragment of viral genetic material in a respiratory sample — is so exacting and time-consuming. Leading labs and equipment makers have added automation and “high-throughput” technology that can run specimens in an hour or so.

Nor can a lack of funding be blamed. In April, Congress authorized the federal government to distribute $25 billion to support all sorts of testing efforts at all levels.

Rather, the backup is like the drinking from a fire hose syndrome: without mechanisms to keep a flow under control, it can become overwhelming.

“We’re putting huge numbers of tests into a small number of labs,” Michael Mina, a Harvard University epidemiologist and infectious disease expert, said during a video conference Wednesday.

To manage, LabCorp, Quest, and other big players say they are prioritizing testing. For hospital patients, patients preparing for surgery, and health-care workers with symptoms, specimens are collected, transported, and processed, and results are provided, in a single day. Everyone else, have patience.

Public health experts have long pushed for the creation of a national system to oversee testing in a public health crisis. It hasn’t happened.

“We do not have a national laboratory strategic plan,” Scott Becker, the chief executive of the Association of Public Health Laboratories, told the New York Times.

Nor is there clear national guidance on how to collect, analyze, and report testing data, so states and the CDC have adopted varying practices.

For Santiago, who is still trying to get her test result, only one thing is clear about the current situation: “We’re feeding into the virus’ spreading.”