Coronavirus Briefing: Omicron, a guide

https://www.nytimes.com/2021/12/17/us/coronavirus-briefing-what-happened-today-omicron-a-guide.html

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Unvaccinated students exposed to Covid-19 can stay in school under a new testing protocol, the C.D.C. said.

In a trial, Pfizer’s low-dose shot did not provoke an adequate immune response in 2- to 5-year-olds.

Early data suggests that South Africa’s Covid hospitalizations are lower in the Omicron wave, but there are caveats.

Get the latest updates here, as well as maps and a vaccine tracker.

There’s still a lot we don’t know about Omicron, but this is abundantly clear: It’s highly contagious and it spreads quickly.

After erupting in countries including South Africa, Britain and Denmark, the U.S. may be next. A lab at the University of Washington reported that the share of viral samples that seem to contain Omicron’s telltale pattern of mutations had jumped to 20 percent from 3 percent in a matter of days.

The variant has been detected in 39 states, with reports of big spikes in New York and other cities. (It’s worth noting that while Omicron is spreading rapidly, the Delta variant is still widespread, too.)

Early evidence suggests that the Omicron variant can evade some amount of immunity, from both vaccination and previous infection. That, coupled with its breakneck speed, means that infections in vaccinated people will most likely become increasingly common in the coming weeks. The holidays may supercharge this trend.

So how should you approach life in the age of Omicron? While the guidance will certainly change as we learn more, here’s an initial guide to navigating the next phase of the pandemic.

What do we know for sure?

The basics haven’t changed. Even in this murky in-between moment where there’s a lot of unknowns about Omicron, the old rules to lower your risk still apply: Reduce your contact with other people, especially in crowded indoor settings; wear a mask, and upgrade it; use home tests before gathering; and get vaccinated, with a booster if possible.

What has changed is that Omicron is better at sidestepping some of the protection that vaccines give us, said my colleague Tara Parker-Pope, the founding editor of Well. Early evidence from South Africa has raised hopes that Omicron may be milder than Delta, but it’s still far too early to make broad conclusions. “Omicron is going to be disruptive for at least the next month or two, but we’re not experiencing a repeat of 2020,” Tara said.

“When we’re in a surge like this, I think we need to think about priorities a little more,” she added. “Maybe I’m going to skip the movie and dining at a restaurant, so it’s safer to spend time with friends on the weekend or visit my parents.”

What if I’m vaccinated?

While Omicron seems able to thwart some amount of immunity, boosters seem to do a good job of preventing infection. Even if you get sick with a breakthrough infection, scientists believe the vaccines still provide solid protection against severe illness and death.

That said, everyone should assume they are less protected now than they were before Thanksgiving.

Ed Yong at The Atlantic put it this way: “As a crude shorthand, assume that Omicron negates one previous immunizing event — either an infection or a vaccine dose. Someone who considered themselves fully vaccinated in September would be just partially vaccinated now (and the official definition may change imminently). But someone who’s been boosted has the same ballpark level of protection against Omicron infection as a vaccinated-but-unboosted person did against Delta.”

(Yong recently canceled his birthday party and explained the risk analysis behind his decision.)

Should I change my plans for holiday gatherings?

There isn’t a simple answer to this question, Tara said: “That said, I can still give you one simple tip that can help you figure it out: Plan your event around the most vulnerable person in the room.”

Think about the things you would need to do to protect an older grandparent, for example, and that will give you an idea of whether the event should go forward with extra precautions, be scaled back or canceled.

You can lower your risk by asking that everyone get a booster, if eligible, and take a rapid test a few hours before the event. Focus on ventilation, and ask everyone to scale back their social activities before the event.

“If you’re celebrating Christmas Eve, get tested on Wednesday and then take a home rapid test on Christmas Eve, right before the party. One doctor I know takes his rapid test in the driveway before he enters his parents house,” Tara said. “I think family gatherings, especially now as we head into our third year of pandemic life, are really important. If everyone is willing to do what’s needed to protect the most vulnerable, you can lower risk and gather more safely.”

What if I feel sick?

Get tested. It’s the only way you’re going to know if what you’re feeling is a cold or Covid. It’s also important to know so that you can inform other people whom you might have exposed, should you test positive.

Now more than ever, it’s a good idea to keep a few rapid tests at home so you can test yourself. If you do test positive with an antigen test, it’s a good idea to follow up with a more sensitive PCR test, my colleague Carl Zimmer said. Try not to expose others: Use a drive-through testing site or walk to a mobile outdoor testing site. If neither of these are options, call your doctor’s office and ask them for guidance.

I tested positive. Now what?

The guidance is the same for Omicron as it is for other variants. If you’re vaccinated, the C.D.C. says you should isolate for 10 days and rest. If you live with other people, you should stay in a specific “sick room” or area, and use a separate bathroom, if available. Wear a mask and don’t share dishes.

The 10-day isolation period begins the first full day after your symptoms develop. If you test positive, but don’t have symptoms, the 10-day clock starts the day after you test positive. If you develop symptoms later, reset the clock. At any point if you have an emergency warning sign, like breathing trouble, go to the hospital.

I’m traveling for the holidays. What if I test positive away from home?

The responsible thing to do is to isolate for 10 days, but whether you’ll be forced to do so depends on where you’re traveling.

In the U.S., it’s mostly up to the individual to decide how to proceed. States, airlines, airports or most other forms of transportation do not require a negative coronavirus test from domestic travelers, with a few exceptions. Dr. Emily Volk, the president of the College of American Pathologists, says isolating after a positive test is “the morally and ethically correct thing to do.”

If you test positive while traveling internationally, the rules will depend on where you are. Some places won’t let you board a plane, while other places might require you to stay in a government hospital for more than 10 days. If you’re traveling abroad, here’s some advice: Learn the local rules and pack as if you’re going to get stuck.

France plans to tighten restrictions on the unvaccinated.

Britain recorded more than 93,000 daily infections, a new high.

For the staff at one inundated Michigan hospital, “you come back to work and you ask who died.”

Boeing joined other federal contractors in dropping its vaccine mandate.

An Italian province has relied on pure air and herbal remedies. But nature isn’t protecting it from the coronavirus.

Three Iranians tried to sue the country’s supreme leader over Covid but were jailed before they could file the complaint.

The N.F.L. rescheduled three games amid an outbreak of “a new, highly transmissible form of the virus.”

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