New Study: Half of Hospitalized COVID Patients Have Mild Case, Are Asymptomatic, or in Hospital for Another Reason

About three million people in the United States with the China Virus have been admitted to hospitals in the past year, data from the Centers for Disease Controls show.

Yet not all of those hospitalized with the virus were hospitalized because of the virus. Instead, the Atlantic reported on September 13, they went into the hospital for another reason, but tested positive after they were there.

That means the data on hospitalizations with the virus might not tell us what we think it does.

The Numbers

“The number of patients hospitalized with COVID-19 in the United States right now is as high as it has been since the beginning of February,” the leftist magazine reported. “It’s even worse in certain places: Some states, including Arkansas and Oregon, recently saw their COVID hospitalizations rise to higher levels than at any prior stage of the pandemic. But how much do those latter figures really tell us?”

Answer: Perhaps not what we think.

Though the number of people in the hospital with the virus “have served as a vital metric for tracking the risks posed by the disease,” the magazine reported, a yet-to-be peer-reviewed study of records “suggests that the meaning of this gauge can easily be misinterpreted — and that it has been shifting over time.”

That’s because one cannot understand the significance of the number of hospitalizations without knowing how the virus is affecting any given individual.

“Until now, that’s been almost impossible to suss out,” the magazine reported:

The federal government requires hospitals to report every patient who tests positive for COVID, yet the overall tallies of COVID hospitalizations, made available on various state and federal dashboards and widely reported on by the media, do not differentiate based on severity of illness. Some patients need extensive medical intervention, such as getting intubated. Others require supplemental oxygen or administration of the steroid dexamethasone. But there are many COVID patients in the hospital with fairly mild symptoms, too, who have been admitted for further observation on account of their comorbidities, or because they reported feeling short of breath. Another portion of the patients in this tally are in the hospital for something unrelated to COVID, and discovered that they were infected only because they were tested upon admission. How many patients fall into each category has been a topic of much speculation. In August, researchers from Harvard Medical School, Tufts Medical Center, and the Veterans Affairs Healthcare System decided to find out.

For instance, doctors in California found that 40 to 45 percent of virus-positive pediatric hospital patients were admitted for another reason. That is, the “COVID diagnosis was merely incidental.”

Thus, the authors of the latest study “analyzed the electronic records for nearly 50,000 COVID hospital admissions at the more than 100 [Veterans Administration] hospitals across the country,” the magazine reported:

Then they checked to see whether each patient required supplemental oxygen or had a blood oxygen level below 94 percent. (The latter criterion is based on the National Institutes of Health definition of “severe COVID.”) If either of these conditions was met, the authors classified that patient as having moderate to severe disease; otherwise, the case was considered mild or asymptomatic.

The study found that from March 2020 through early January 2021 — before vaccination was widespread, and before the Delta variant had arrived — the proportion of patients with mild or asymptomatic disease was 36 percent. From mid-January through the end of June 2021, however, that number rose to 48 percent. In other words, the study suggests that roughly half of all the hospitalized patients showing up on COVID-data dashboards in 2021 may have been admitted for another reason entirely, or had only a mild presentation of disease.

Let’s read that again: About 50 percent of COVID-positive VA patients in the hospital were there for another reason or had a mild case of the disease.

Of vaccinated patients, 57 percent presented with mild or asymptomatic disease, and “unvaccinated patients have also been showing up with less severe symptoms, on average, than earlier in the pandemic,” the Atlantic reported

The study found that 45 percent of their cases were mild or asymptomatic since January 21. According to Shira Doron, an infectious-disease physician and hospital epidemiologist at Tufts Medical Center, in Boston, and one of the study’s co-authors, the latter finding may be explained by the fact that unvaccinated patients in the vaccine era tend to be a younger cohort who are less vulnerable to COVID and may be more likely to have been infected in the past.

New Metric

One takeaway from the study is that vaccines are protecting hospital patients from serious disease, the magazine reported, and those hospitalized with the virus “need only minimal treatment,” which might certainly be true.

“But the study also demonstrates that hospitalization rates … can be misleading, if not considered carefully,” the story continued:

Clearly many patients right now are seriously ill. We also know that overcrowding of hospitals by COVID patients with even mild illness can have negative implications for patients in need of other care. At the same time, this study suggests that COVID hospitalization tallies can’t be taken as a simple measure of the prevalence of severe or even moderate disease, because they might inflate the true numbers by a factor of two.

Thus, “we should refine the definition of hospitalization,” Doron told the magazine. “Those patients who are there with rather than from COVID don’t belong in the metric.”