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Texas has identified its first case of the omicron COVID-19 variant, a strain flagged as potentially more infectious than any that has come before it, including the delta variant responsible for surges still happening across the country, state health officials said on Monday.

The variant was identified in Texas in a Harris County woman in her 40s, according to the Texas Department of State Health Services and county Judge Lina Hidalgo.

Many questions still surround omicron, even as it remains high on the radar of state and federal health officials.

While early indicators suggest the variant is very contagious, it’s still unknown whether it will infect people at a faster rate than the delta variant, which currently represents nearly all the active cases in Texas. Little is also known about the severity of disease the omicron variant causes.

It could also take another month, experts say, to figure out how effective vaccines or natural immunity will be against the omicron variant.

Other unknowns include how sick it will make those infected and whether it will be milder or more aggressive than the delta variant.

Hidalgo said the woman in whom the variant was detected has no recent history of travel.

As omicron has been circulating in other countries for several weeks, the confirmation of its arrival in Texas was no surprise to state health officials, who said it’s likely that the variant has been present in the state for longer than that.

The first case of the omicron variant in the U.S. was reported Wednesday in California. Since then, more cases have popped up in other states, including New York and Minnesota.

Texas health officials are already on the lookout for a potential holiday surge — whether it’s caused by delta, by omicron or any other variant — and pushing for more Texans to get their vaccines. About 55% of Texans have been fully vaccinated as of Dec. 1.

“Prevention is important, and vaccination remains our best prevention tool,” said Chris Van Deusen, spokesperson for the Texas Department of State Health Services.

Federal health officials are also urging eligible vaccinated adults to get their booster shots to increase their protection against COVID-19. Among fully vaccinated Texans, only 18.5% of them have gotten a booster shot, according to state health numbers.

Texas hospitals are still in the throes of a staffing shortage after two years of deadly surges and a summer wave of deaths and hospitalizations that saw record numbers of ICUs filled to capacity.

A wave of illness worse than delta would further strain those already stretched resources, hospital officials say — but if the surge is a milder form of illness, it may not have much effect on hospital capacity or the impact of the pandemic in Texas.

“Right now, at least for us, it has been 100% delta for weeks,” said Dr. Randall Olsen, medical director of the Molecular Diagnostics Laboratory at Houston Methodist Hospital, where nearly every positive COVID-19 sample is tested to identify variants. “Delta has outcompeted every other variant that we had prior to it. So [omicron] … will have to find a foothold, and if it’s going to be successful, it’s going to have to displace delta as the major cause [of new cases]. It’ll have to be a substantial pathogen to do that.”

Early signs on whether it is capable of that are mixed.

The variant has been identified in more than two dozen countries within the last month. But no deaths have been linked to omicron so far. A South African doctor who was instrumental in identifying early cases said the symptoms in omicron patients so far have been mild. And there are early indicators that the booster shot helps protect against omicron.

At the same time, hospitalizations have spiked in recent weeks in the South African province where omicron was first identified — and where the new strain has overtaken the delta variant in prevalence among new cases there. A South African infectious disease expert told Reuters on Tuesday that omicron is showing signs of being highly contagious.

And the structure of the omicron variant has an unusually high number of mutations, which caught the attention of the World Health Organization last week both because it’s unique and because that structure could give the virus more opportunities to spread.

Scientists still don’t know where the variant originated.

Omicron is one of five COVID-19 variants currently labeled by the WHO as variants “of concern,” meaning that their genetic makeup gives them the potential to create large surges or change the course of the pandemic for the worse.

The most powerful so far has been the highly contagious delta variant, which infected people at a faster rate than any other strain and kept other variants from spreading widely.

Still the most prevalent variant worldwide, delta raged through unvaccinated communities both in Texas and across the country over the summer, fueling a new rise in cases, hospitalizations and daily death counts that reached some of the highest levels of the pandemic.

The delta variant, discovered in India in late 2020 but first identified in the U.S. in March, is the variant responsible for the increasing numbers of cases and hospitalizations currently being seen in West Texas and states such as New Mexico and Colorado, experts say.

“I think it still remains to be seen if this [omicron] is going to overtake the delta variant, but there is some concern … that it’s possible that might happen,” said Dr. Jason Bowling, epidemiologist for University Health in San Antonio. “For a while it’s been all delta, delta, delta. …

“There might be a new kid on the block.”

Kailyn Rhone contributed to this story.