New research by Canadian scientists published in the Journal of Theoretical Biology suggests that rates for COVID-19 may be close to endemic levels.
A disease outbreak is endemic when it is consistently present but limited to a particular region, according to the Mailman School of Public Health at Columbia University. “This makes the disease spread and rates predictable. Malaria, for example, is considered endemic in certain countries and regions.”
Dr. F. Perry Wilson, associate professor at the Yale School of Medicine, manages a program called “DOM-CovX” – Yale’s proprietary COVID-19 Explorer. The program includes data on all 32,185 patients who were hospitalized at all Yale-affiliated hospitals since the start of the pandemic, including their relevant lab values, vital signs, medications, procedures, and outcomes – that’s nearly 30,000 data points per individual.
Wilson pointed out that there are still about 400 deaths per day from COVID-19 in the U.S., and if that’s the new normal, it’s concerning.
“To put that in context, in a pretty bad flu year, we'd see about 100 deaths a day, you know, something on the order of 35,000 to 40,000 deaths per year from flu,” he said. “So this is still four times higher than that. And if this does turn out to be the endemic rate of COVID-19, if this is what we’re facing indefinitely into the future, it’s actually a rather difficult situation.”
In a new disease like COVID-19, the expected baseline level was zero prior to the public’s knowing of its existence.
“And the question now becomes, what is the expected baseline level? And are we above it or below it right now?” Wilson said.
The answer depends on whom you ask.
The recent Canadian research and other modeling studies are suggesting an end to the pandemic, and pharmaceutical executives also announced that COVID-19 is endemic in the U.S. And the federal COVID-19 emergency is set to end May 11.
Dr. Ulysses Wu, an infectious disease expert at Hartford Hospital, emphasized that it’s important to know whether the deaths are due to COVID-19 or a comorbidity that exacerbated another morbidity that resulted in death.
“So that’s one question we need to answer,” Wu said.
“And then the second question is [that] we will move into some sort of seasonality, similar to influenza,” he said. “So again, there probably won't be this baseline of mortality every single week, but instead would wax and wane.”
Wu said the sign that the U.S. is moving toward the endemic stage is the prevalence of the omicron variant, which spread in other parts of the world before it spread in the U.S. prior to the respiratory season.
“So if you remember the year before that, delta actually happened in the late summer,” he said. “And so during that time, there was not that seasonality. So I think we are moving in that direction.”
Ulysses said much depends on how this summer, spring and fall season pan out.
“If we can get the numbers down to a small level or a low level of transmission, then we could start saying, ’Yeah, maybe we’re starting to enter the endemic phase of seasonality with this disease, or hopefully it occurs with the other respiratory viruses,’” he said. “And then we can take precautions against all of them all at the same time.”
