Two Studies Show Major Drop in COVID-19 Death Rates

Health officials transport the body of a coronavirus victim in Brooklyn in April. Photo: Anadolu Agency via Getty Images

Coronavirus cases are growing at alarming rates in the Mountain West, Great Plains, and Midwestern regions, and the daily number of positive tests nationwide has returned to a number not seen since August, when 1,000 Americans were dying from the virus most every day. Fourteen states have set recent hospitalization records, and to prepare for the uncontrolled spread in his state amid shrinking numbers of hospital beds, Governor Tony Evers opened a field hospital at the Wisconsin State Fairgrounds last Wednesday.

Despite this solemn trajectory, deaths have remained steady throughout October, and according to two new peer-reviewed studies, there is some hope that death rates will not return to the levels seen in northeastern states like New York, New Jersey, and Massachusetts at the beginning of the crisis last spring.

The first study, shared online before publication next week in the Journal of Hospital Medicine, found that the mortality rates among 5,000 hospitalized patients in the NYU Langone Health system in New York City dropped by 18 points between March 1 and June 20. At the beginning of the study, admitted patients had a staggering 25.6 percent chance of dying; at the end, that number was at 7.6 percent. Crucially, the researchers adjusted for risk factors including age and diseases, and still found that death rates dropped for all groups, even among older patients.

Another study shared online before publication in Critical Care Medicine provided similar hope for the coming season, which CDC director Robert Redfield has projected to be “one of the most difficult times that we’ve experienced in American public health.” In the United Kingdom, between the beginning of the pandemic and late June, mortality rates among hospitalized patients dropped by close to 20 percentage points. Like the study in the U.S., the drop “remains after adjustment for patient demographics and comorbidities suggesting this improvement is not due to changing patient characteristics.”

Leora Horwitz, a doctor who studies population health at NYU’s Grossman School of Medicine and an author on the American study, told NPR that the change in mortality rates could be traced back to multiple public-health and medical advances in preventing and treating COVID since the pandemic began. Mask-wearing helps decrease the viral loads that people are exposed to — which can result in less severe cases — while doctors have learned how to identify and treat the immune-system overreactions known as cytokine storms that killed many patients in the spring. One doctor involved in the U.K. study found that keeping hospitals well below their maximum capacity helps keeps staff focused on the patients already admitted, adding more importance to the directives for people to wear masks and practice social distancing. “All of the above is often the right answer in medicine, and I think that’s the case here, too,” Horowitz said.

Despite these advancements — and in the midst of a tremendous international race for a vaccine — the coldest months of the year will bring increased challenges, as people inevitably gather indoors, drier winter air increases the spread of pathogens, and hospitals manage COVID patients and the seasonal rush of those sick with the flu.

New Studies Show Major Drop in COVID-19 Mortality Rates