(NEXSTAR) – There’s a lot we don’t yet know about the omicron variant of COVID-19, which is starting to spread around the world and has been detected multiple times here in the U.S. There are signs out of South Africa it may cause different symptoms – but it’s too early to draw broad conclusions. It’s also not yet clear if it’s better at evading vaccine protection than previous variants.

But there’s one thing we keep hearing from the scientists who’ve gotten a close look at the omicron version of the virus: It’s really mutated.

“This is probably the most mutated virus we’d ever seen,” Alex Sigal told CBS News. Sigal leads a team of researchers working to learn more about omicron.

Lawrence Young, a virologist at the University of Warwick, described omicron as “the most heavily mutated version of the virus we have seen,” including potentially worrying changes never before seen all in the same virus.

More mutations don’t necessarily make a virus more dangerous, either. “In principle, mutations can also work against each other,” Jesse Bloom, an evolutionary biologist in Seattle, told the New York Times.

But viruses, like other organisms, evolve over time to increase their chance of survival. A stronger virus, of course, is generally bad news for us people. That’s why scientists are initially concerned when they see a highly mutated virus.

Of omicron’s many mutations, about 30 of them are on a part of the virus called the spike protein. That concerns scientists because it could affect how transmissible the variant is.

Sharon Peacock, who has led genetic sequencing of COVID-19 in Britain at the University of Cambridge, said the data so far suggest the new variant has mutations “consistent with enhanced transmissibility,” but said that “the significance of many of the mutations is still not known.”

But scientists who’ve gotten a close look also note omicron lacks some of the mutations that delta has that make it highly contagious. There’s a chance the delta variant, the dominant strain in the U.S. right now, is still more transmissible than omicron, so omicron may never take off.

“That’s really the big question. You know, when it gets into a population that has Delta, is it going to out-compete or not out-compete?” Robert Garry, a virologist at Tulane University, told CNN.

In addition to mutations that make omicron more contagious, scientists are also looking at any mutations that might cause more severe disease or more easily evade the vaccines.

“There is currently no information to suggest that symptoms associated with omicron are different from those from other variants,” the World Health Organization said. It said there’s no evidence – yet – that COVID vaccines, tests and treatments are any less effective against omicron.

Some experts say that all of omicron’s mutations could mean that vaccine makers may have to adapt their products at some point. That also remains to be seen.

The Associated Press contributed to this report.