Scientists at the University of Oxford on Tuesday announced that a common, low-cost steroid called dexamethasone reduced the risk of death among patients with severe cases of Covid-19—but some experts are warning the results should be viewed with caution.

Your top resources for Covid-19 response and resilience

US new coronavirus cases surpass 2.1M, deaths near 117K

The announcement comes as the global coronavirus pandemic continues to worsen in many countries. In the United States, officials as of Wednesday morning reported 2,148,900 cases of the new coronavirus—up from 2,124,000 cases as of Tuesday morning.

Data shows that Puerto Rico and at least 20 states—Alabama, Alaska, Arizona, Arkansas, California, Florida, Georgia, Hawaii, Idaho, Louisiana, Nevada, North Carolina, Oklahoma, Oregon, South Carolina, Texas, Utah, Vermont, Wyoming, and Montana—saw their growth rates of newly reported cases of the novel coronavirus accelerate over the past 14 days. On Tuesday, officials in six of those states—Arizona, Florida, Oklahoma, Oregon, and Texas—reported their largest single-day increases in new cases.

Officials have said their states' recent spikes in new cases of the coronavirus are a result of businesses reopening and residents easing social distancing, and officials pointed in particular to large gatherings over Memorial Day weekend as one reason for the increases.

Meanwhile, data shows that the growth rates of newly reported cases over the past two weeks remained nearly constant in Iowa, Kansas, Kentucky, Mississippi, Missouri, New Mexico, North Dakota, South Dakota, Tennessee, Washington, West Virginia, and Guam.

In addition, Washington, D.C., and 19 states—Colorado, Connecticut, Delaware, Illinois, Indiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Nebraska, New Hampshire, New Jersey, New York, Ohio, Pennsylvania, Rhode Island, Virginia, and Wisconsin—saw their growth rates of newly confirmed cases decrease over the past 14 days.

As of Wednesday morning, U.S. officials also had reported a total of 116,979 U.S. deaths linked to the new coronavirus—up from 116,207 deaths reported as of Tuesday morning.

Steroid reduces death risk among severely ill Covid-19 patients, scientists say

As the numbers of newly reported coronavirus cases and related deaths continue to rise throughout the United States, researchers are examining potential treatments for Covid-19, the disease caused by the virus.

The low-cost steroid dexamethasone is one of the medications researchers have been evaluating as a possible treatment for the disease. Researchers and doctors have been testing whether the steroid, which costs less than $1 per day of treatment for a single patient, helps reduce inflammation in Covid-19 patients experiencing so-called "cytokine storm," which is an uncontrolled immune response that can be triggered by the new coronavirus and result in death. Data published earlier this year from a small clinical trial conducted in Spain had suggested the steroid could reduce how long a patient with acute respiratory distress, which is a common symptom among patients with severe Covid-19, is on a ventilator and may reduce the risk of death among such patients.

On Tuesday, Oxford University scientists in a press release announced that, in a randomized controlled clinical trial, which is viewed as the gold standard for medical research, dexamethasone reduced deaths among severely ill, hospitalized Covid-19 patients.

For the clinical trial, the researchers administered low doses of dexamethasone either orally or intravenously once per day to 2,104 patients at National Health Service (NHS) hospitals with severe cases of Covid-19. In comparison, 4,300 hospitalized patients with severe cases of Covid-19 served as a control group and received standard care for the disease.

According to the researchers, when compared with the control group, dexamethasone decreased the number of deaths among patients on ventilators by one-third and reduced the number of deaths among patients being treated with supplemental oxygen by one-fifth. However, the researchers found that the steroid wasn't associated with any benefits among patients who were not receiving respiratory support.

The researchers said the drug appears to protect the body's tissues by reducing inflammation caused by the immune system. Stuart Neil, a professor of virology at King's College London, said, "What this is effectively doing is tamping down inflammatory responses in patients. It's almost certain this is affecting the body's response against the virus, rather than inhibiting the virus itself."

The researchers estimated that up to 5,000 deaths could have been prevented if doctors had used the steroid to treat hospitalized patients with severe cases of Covid-19 in Britain since the beginning of the pandemic.

Peter Horby, one of the chief investigators on the clinical trial and a professor of emerging infectious diseases at the University of Oxford, said, "Dexamethasone is the first drug to be shown to improve survival in Covid-19. The survival benefit is clear and large in those patients who are sick enough to require oxygen treatment."

Horby added that dexamethasone should now become the "standard of care in these patients," noting that the steroid is low-cost, widely available, and could be used immediately.

Matt Hancock, Britain's health secretary, said NHS providers as of Tuesday afternoon could start using dexamethasone as a standard treatment for hospitalized Covid-19 patients.

The World Health Organization (WHO) on Tuesday announced it would update its clinical guidance on how to treat patients with Covid-19 to reflect the researchers' findings. In addition, the group said it "will coordinate a meta-analysis to increase our overall understanding of this intervention."

Experts say findings should be viewed with 'cautious optimism'

Many experts welcomed the findings with "cautious optimism," Axios' "Vitals" reports, particularly because the researchers have not yet published their methodologies and findings in a scientific journal or had their research peer-reviewed.

Sam Parnia, a pulmonologist and associate professor of medicine at the Grossman School of Medicine at New York University, said, "Assuming that when it goes through peer review it stands—and these are well-established researchers—it's a huge breakthrough, a major breakthrough. I cannot emphasize how important this could be."

Atul Gawande—a surgeon, author, and public health researcher—in a tweet posted Tuesday wrote, "It will be great news if dexamethasone, a cheap steroid, really does cut deaths by 1/3 in ventilated patients with [Covid-19]." However, he wrote that amid recent "retractions and walk backs" of studies and research findings related to the new coronavirus, "it is unacceptable to tout study results by press release without releasing the paper."

Likewise, Kathryn Hibbert, director of the medical ICU at Harvard's Massachusetts General Hospital, cautioned, "We have been burned before, not just during the coronavirus pandemic but even pre-Covid, with exciting results that when we have access to the data are not as convincing."

Trump admin pledges to make coronavirus vaccine available at no-cost for 'vulnerable' Americans

Also on Tuesday, Trump administration officials pledged to offer any future vaccine against the new coronavirus at no-cost to "vulnerable" Americans who cannot afford to pay for it.

According to STAT News, an administration official who spoke on a condition of anonymity during a call with reporters on Tuesday said, "For any American who is vulnerable, who cannot afford the vaccines, and desires the vaccine, we will provide it for free."

In addition, a senior administration official during a briefing with reporters on Tuesday said the federal government has been talking with U.S. health insurers about potentially covering a vaccine against the new coronavirus without cost-sharing requirements for their enrollees, the Associated Press reports. According to CNBC, the official said some insurers have expressed an "eagerness" to cover the vaccine for enrollees without copayments (Shumaker/O'Brien, Reuters, 6/16; Reiman, Forbes, 6/16; Mueller/Rabin, New York Times, 6/16; New York Times, 6/17; Marchione, Associated Press, 6/15; Reuters, 6/17; Owens, "Vitals," Axios, 6/17; Erman/Steenhuysen, Reuters, 6/16; Herper, STAT News, 6/16; Edwards, NBC News, 6/17; Lacher, STAT News, 6/16; Alonso-Zaldivar, AP/ABC News, 6/16; Lovelace/Feuer, CNBC, 6/16; Adam et al., Washington Post, 6/16; New York Times, 6/17).