“This is the first recession since the ACA, and it’s also the first pandemic since the ACA, and it’s all happening at the same time, so it’s hard to say how this is all going to unfold,” said Cynthia Cox, vice president at the nonprofit Kaiser Family Foundation in Washington, D.C., where she conducts research on health care and the effects of the ACA. “But this will be the first true test of how well the ACA works at preventing significant coverage loss.”

Cox said she “wouldn’t be surprised” if the number of uninsured increased, but the extent depends on various factors. Workers who lose their jobs and their health coverage have some options for staying insured. Some may have spouses with employer-sponsored health coverage they can use. Others may opt to pay for COBRA coverage or buy insurance from a subsidized ACA health care exchange, though both of those options might be too pricey for some people to afford. Some people may qualify for Medicaid, even more so in states that expanded Medicaid coverage through the ACA.

The Trump administration decided against a plan to open a special enrollment period for federal ACA marketplace exchanges for people who already had been uninsured before the pandemic. Some states, however, have opened enrollment in their own exchanges. And newly unemployed people still would be eligible to enroll in the federal exchanges because of the recent change in their coverage status.

Americans who recently lost their jobs or already had been uninsured can explore their options on the ACA website HealthCare.gov.

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Having health care coverage can be critical for anyone facing a costly illness, including COVID-19. On Friday, the Trump administration announced plans to use federal stimulus funds to pay hospitals for treating uninsured coronavirus patients.

“This could be a major catastrophic illness, both from a physical perspective but also from a financial perspective,” said Sara Collins, vice president for health care coverage and access at the Commonwealth Fund, a nonprofit foundation that studies health care, in New York. “It’s the kind of event when you’re uninsured that could really sink you.”

For uninsured, hospital costs could top $40,000

Because of the ACA, not only were more Americans insured going into this health crisis than a decade ago, but there also are caps on how much insured people have to pay out-of-pocket for their care.

However, there are no cost limits for uninsured Americans, numbering nearly 28 million before the pandemic, and the bills that arrive in the mail can deliver quite a shock.

That was the case for one uninsured woman who received a bill for nearly $35,000 for COVID-19 treatment at a Massachusetts hospital.

Most people afflicted with the coronavirus are expected to recover at home, if they even know they are infected. But for those who require hospitalization for COVID-19, the price tag for their treatment could be staggering, upwards of $40,000 or more for people who are uninsured, Cox said.

In a new analysis, the Kaiser Family Foundation estimated the average cost of COVID-19 hospital treatment to be $20,292, based on typical costs for pneumonia treatment for people with employer coverage.

Costs could be much higher for patients with the most severe COVID-19 cases that require ventilator support and prolonged hospital stays.

“The negotiated rate that large health insurance companies are paying to providers for someone with pneumonia with significant complications is in the ballpark of $20,000,” Cox told NBC News. “You can bet that hospitals would send a bill for probably double that for someone who’s uninsured.”

By comparison, people with health insurance and protections from the ACA, including limits on out-of-pocket costs, might receive bills for typical COVID-19 hospitalization that are anywhere between $1,300, for people who receive health coverage from a large employer, to upwards of $6,000 for those who bought insurance in the marketplace and don’t qualify for extra cost breaks, according to Cox.

So highlighting a wide disparity, individual out-of-pocket costs for a COVID-19 hospitalization could range from $1,300 for those with health coverage to $40,000 or more for the uninsured. “We’re talking about the difference between something that people might be able to pay off eventually and something that could cause bankruptcy,” Cox said.

Some insurers are now waiving patient cost-sharing for COVID-19 treatment. People who can’t afford their medical bills can try to negotiate the costs down with the hospital and providers or see if there are any hospital charity care programs that might help, but there are no guarantees.

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Besides the risk of sky-high medical bills, uninsured people also can face difficulty accessing treatment and getting the care they need to stay healthy. Knowing they aren’t covered and can’t afford medical expenses may prevent them from seeking timely care, a decision that could prove deadly with the coronavirus.

“Having insurance is the most important factor in guaranteeing people have access to health care,” Collins said. “It removes that financial barrier, even though there are people who are facing significant out-of-pocket costs still.”

No one knows the financial toll that this crisis will take on the U.S. health system, but the New York-based nonprofit group FAIR Health recently estimated that COVID-19 hospital treatment costs could total anywhere from $139 billion to $558 billion.

Threats to Obamacare

The ACA has known flaws that will continue to present challenges during this devastating health crisis. The law never achieved universal health coverage, and insurance has remained unaffordable for many. Some people who make too much money for financial help still can’t afford to buy coverage through health exchanges and they don’t qualify for Medicaid. Deductibles can be too high even for workers with health coverage through their employers. And hospital patients may receive “surprise” bills for unexpected out-of-network care they weren’t anticipating, such as from an anesthesiologist who is not part of their plan.

Still, an NBC News/Wall Street Journal national poll conducted last month found that the ACA is as popular as it ever has been, with 42 percent of registered voters saying they believe the law is a good idea, compared with 35 percent who think it’s a bad idea and 23 percent who have no opinion.

“We know that there already are 20 million more people now who have insurance than would have if it weren’t for the ACA just under the normal circumstances,” Cox said. “But now that we’re entering into likely another recession where people are losing their jobs, the ACA will further work to make sure that fewer people fall through the cracks.”

That’s as long as the ACA remains the law of the land. Obamacare has faced repeated attacks and the Trump administration has vowed to repeal it. In the fall, the Supreme Court is scheduled to hear a case that challenges the constitutionality of the law.

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