Chicago's first case of the Omicron variant was detected Tuesday in a resident who was both vaccinated and boosted.

Why it matters: The new variant could boost already surging cases in Chicago.

Threat level: The city is taking several precautionary measures, health commissioner Allison Arwady said Tuesday at her weekly press conference, including:

• Contacting all U.S. citizens arriving at O'Hare from eight restricted countries.
• Testing known contacts of individuals infected with Omicron.
• Doubling the number of COVID samples sequenced at public labs.
• Requiring all international travelers to get COVID tests within a day of their trip.

The latest: Thanksgiving guests with the the sniffles drove the post-holiday Delta surge.

• "We found people went to Thanksgiving even though they had some symptoms they thought were a cold ... and some cases of folks who had gone to get tested and hadn't yet gotten the [positive] results back," the health commissioner said.
• "Stay home if you feel sick."

What's next: Arwady answered questions on the need for:

• Omicron boosters: "We might. We'll know in another two weeks or so once all the data has been collected."
• Continued indoor masking: "Yes, especially as cases are on the increase. We will be doing messaging on [best] types of masks soon."
• Proof of vaccination at more public places: "Yes, I think we might. I'm more interested in that than major shutdowns."

Despite two decades of tightened carry-on rules, airline passengers at O'Hare continue to try to bring prohibited stuff on planes. Especially weapons.

Why it matters: First, it's kind of scary. But second, these weapons can get passengers in trouble and hold up already long holiday travel lines.

Zooming in: We asked the Transportation Security Administration (TSA) for a list of the most commonly stopped items at O'Hare (outside of oversized liquids) in 2020.

• Most common: "Firearms, stun guns/cattle prods/shocking devices, switchblade-type knives, double-edged type knives and fireworks."
• Found less often, but still prohibited: "Ammunition, BB guns/pellet guns, axes/hatchets, firearm replicas/toy guns, throwing stars, brass knuckles and bows/arrows."

Party trick: At your next gathering (or virtual cocktail hour), use the TSA's approved items list for a game called, "Can you bring this on a plane?" Real items on the list:

🥃 Alcohol over 140 proof? NO

🦴 Artificial skeleton bones? YES

🐻 Something called bear bangers? NO

🍼 Breast milk? YES

Day four in our series of local gift ideas is aimed at the bookworms on your list. You can't go wrong with a batch of fine books recently released by Chicago journalists:

• As the Wicked Watch by Tamron Hall with T. Shawn Taylor.
• Three Girls from Bronzeville by Dawn Turner.
• Christmas with Elvis by Robert K. Elder.
• Chicago Exposed: Defining Moments from the Chicago Sun-Times Photo Archive, edited by Richard Cahan and Michael Williams.
• The Ultimate Chicago Pizza Guide by Steve Dolinsky.

Local love: You can get all these books from local independent bookstores, many of which can ship the books if needed.

• Some are hosting upcoming signings for Christmas with Elvis in Forest Park or the Ultimate Chicago Pizza Guide in Crestwood.

With so many high profile carjackings this year, it may be hard to believe Chicago's per capita car thefts last year were lower than in many other big U.S. cities.

Why it matters: Like a lot of Chicagoans, we're alarmed by local crime statistics but think it's important to highlight where we are doing better comparatively.

By the numbers: Chicago ranked fifth best out of 18 cities in a study of 2020 data by insurance site Compare.com

• We had 362 incidents per 100,000 residents compared to 5,139 in list-leading Denver.
• Researchers defined "incidents" as auto theft and burglary as well as attempted auto theft and burglary.

Car theft timing: Monday and Friday are the riskiest days for car thefts and break-ins, according to the report.

• Most vehicle incidents happened from 5 to 10pm.

The rest of the list: New York City, Boston, Dallas and San Diego showed lower car thefts per capita than Chicago.

🚙 Chicago drivers spent 104 hours in traffic in 2020, more than any other U.S. city — despite downtown trips dropping by 21%. (Axios)

🎓 WBEZ's Sarah Karp talks to City Cast about CPS' stressful high school application process that wraps up next week. Monica is still traumatized from the process. (CityCast)

🥣 Curious City answers why so many Chicago restaurants serve split pea soup on Wednesday. Go get some today. (WBEZ Curious City)

The Chicago Teachers Union is asking CPS for more vaccination locations after the death of an elementary school aid. (BlockClubChicago)

Hint: This is the roof of a city structure built in 2012 where you can find slips and usually feel safe.

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