(NEXSTAR) – When the omicron variant emerged, it immediately made its presence known, spreading like wildfire and driving the United States’ largest coronavirus case spike yet. In 2023, the record-breaking spike is over, but omicron isn’t.

According to tracking by the Centers for Disease Control and Prevention, omicron and its subvariants make up 99.9% of current COVID-19 spread. The delta variant, which overloaded hospitals and killed thousands in late summer 2021, is now responsible for 0% of cases. “Other” variants are responsible for 0.1%.

What happened to the variants that once wreaked havoc? “For all intents and purposes, we can consider them gone,” said Dr. David Dowdy, an epidemiology professor at Johns Hopkins Bloomberg School of Public Health.

As the virus spawned new variations that were better at infecting people, they edged out old types, including the alpha variant of early 2020 and delta from 2021. It happens through a “continual game of cat and mouse between the virus and our immune systems,” Dowdy said.

But a new variant isn’t necessarily bad news. The alpha and delta variants were actually known to make people more ill, and as those variants faded away, so did some of their most severe symptoms and outcomes.

“There’s this tendency to think that just because we are seeing new variants, that means that the virus is continually getting worse and worse for us. And that’s not the case,” said Dowdy. “I think the flu is a good example of this. We have a new variant of the flu every year. That doesn’t mean that that every year’s flu season is worse than the one before.”

One symptom we don’t see nearly as often is the loss of taste and smell, which was more common with early coronavirus variants.

Could the old variants come roaring back one day? It’s more likely we’d see something new, explained Dr. Davidson Hamer, a professor of Global Health and Medicine at Boston University’s Schools of Public Health and Medicine.

“It’s more likely that novel variants are going to rise, that have even more mutations, that make the virus more fit to spread,” Hamer told Nexstar. “Usually, it’s sort of the old strain that evolves, or evolves further, but It never really goes back to where it came from.”

While omicron is generally less deadly than delta or alpha, it’s certainly not harmless. More than 3,000 people were dying every day at the height of the omicron surge. Over the past month, the average daily death toll has been between 400 and 600.

Nexstar’s Michael Bartiromo contributed to this report.