As we head into year three — yes,
three — of the COVID-19 pandemic, many of us are still grappling with the idea
that there will not be a quick and definite end to this situation. And we may
be living with the virus for quite some time as we transition into what experts
call the "endemic" phase.
But what that looks like is still up for debate. Here's what we
know about endemicity — and experts' best guesses about what the future of
COVID-19 may involve.
What does "endemic" actually mean?
Dr. Raed Dweik, pulmonologist, critical care specialist, and chair
of the Cleveland Clinic's Respiratory Institute, said that pandemic, epidemic,
and endemic are "terms that people are kind of confused about" right
now.
A pandemic is a sudden increase in the number of cases of a
specific illness spread to different parts of the globe. An epidemic is a surge
in the circumstances confined to a smaller area, like a foodborne illness
outbreak in a few states or the 2014 Ebola outbreak.
On the other hand, an endemic virus is always present in a
specific area of the world or among a particular population. According to the
Centers for Disease Control and Prevention, a virus's endemic level is its
baseline, or "the amount of a particular disease that is usually present
in a community." It's not always present at the ideal level, but it is
expected and predictable.
Dr. Richard Martinello, associate professor of medicine in the
department of infectious diseases at Yale School of Medicine, said that
definitions like these are "very generic." They also don't "give
us any parameters to say when something goes from a pandemic to an
endemic." Experts do, however, have a few predictions for how COVID-19
will affect our future — and how the pandemic might very well end soon.
What will the endemic phase look like for COVID-19?
Dr. Bernard Camins, medical director for infection prevention at
the Mount Sinai Health System, said that many experts now see COVID-19 becoming
endemic similar to the seasonal flu.
"When it doesn't disrupt everyday life, it's endemic,"
he said. Even severe flu years do not disrupt health care, transportation,
businesses, or our other daily routines to the large extent that COVID-19 has,
according to Camins.
"What we usually see in a pandemic are waves of
disease." And those waves of disease are precisely what we've been through
and are still going through," Martinello said. "However, when a
disease is endemic, we expect it to follow a seasonal pattern, such as
influenza or some of our cold virus viruses."
That means we could see more breakouts later this year and
possibly for the next few years (perhaps fueled by new coronavirus variants).
However, due to the population's increasing overall level of immunity — both
from vaccination and infection — those waves are unlikely to be as disruptive
as the delta and omicron surges. "As we move forward with this, the
proportion of the population (with some level of immunity) will grow,"
Camins predicted. "And then we get to endemicity," says the
researcher.
The flu-like scenario, according to Dweik, is "the most
likely and probably the best-case scenario."
What we don't know is how widespread future waves will be or
whether they'll follow the same seasonal patterns as previous waves, according
to Martinello. On the other hand, experts are unsure when the endemic phase
will occur. Meanwhile, they emphasize that COVID-19 is still in its pandemic
phase.
"My hospital has just over 1500 beds, and during the worst
flu seasons, we may see 100 people with the flu in our hospital,"
Martinello said. "However, just a few weeks ago, we had 450 people with
COVID in our hospital... That's the difference: there may be a wave, but the
peak of the wave (when a virus becomes endemic) is very different."
Will we need more boosters, masks, or other precautions in the future?
Whether or not we'll need more COVID-19 shots is defined by two
major factors: how long our current series' protection lasts and whether or not
a variant arises that can significantly bypass that protection. For the time
being, experts say it's too early to tell whether a fourth (or more) dose is
required.
"I suspect we'll be getting an annual vaccine... we'll be
getting a flu shot and the COVID shot, and I think it will become part of our
routine annual vaccinations," Dweik speculated. Camins agreed, adding that
he doesn't think we'll need another booster until this fall at the earliest —
"barring another variant," he said.
One of the benefits of the COVID-19 mRNA vaccine technology is
that it will take much less time to develop new versions of the vaccine to
target different strains than it does for seasonal flu vaccines, according to
Dweik. If and when COVID-19 becomes an actual seasonal illness, they can be
more correctly targeted to what's circulating.
Martinello believes masks will play a more significant role in our approach to preventing disease transmission in general, not just COVID-19. "I don't expect masks to be worn all of the time in classrooms or at work," he said. "However, I believe we will see more individual use of masks." Many of us may choose to wear a mask when we're in a crowded situation or flying — not because there's a public health emergency, but because we don't want to catch a cold."