Covid in DC: What to know about the risks of Omicron and BA.2

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The answer, like much else throughout the coronavirus pandemic, is complicated because it depends on individuals’ personal risk thresholds. And no public outing bears zero risk — especially a formal event like the Gridiron dinner, held inside a hotel basement — with variants as transmissible as Omicron and its sibling, BA.2, circulating widely.

“A tuxedo does not prevent infection,” said William Schaffner, medical director of the National Foundation for Infectious Diseases and professor at Vanderbilt University School of Medicine.

Here’s what you need to know about Covid-19 in the age of Omicron and relaxed public health mitigation strategies:

How serious is the new Covid variant?

Omicron BA.2 is the dominant variant of Covid-19 in the U.S and spreads through the air the same way other coronavirus variants have since late 2019, when the pandemic began, said Linsey Marr, an aerosol expert at Virginia Tech. It’s proven to be far more infectious than the original strain.

“It’s probably that there’s more of it being released into the air, or it takes exposure to less of it to get infected, or it evades the immune system better,” Marr said of BA.2.

While this strain is more transmissible than its predecessors, it’s associated with less severe disease and comes at a time when the country has plenty of vaccines, drugs and other therapeutics to combat it.

Vaccines are the gold-standard of protection but aren’t bulletproof.

Being fully vaccinated and up to date on booster shots remains the best way to protect yourself from a severe case of Covid. But with the amount of time that has passed since many people were originally immunized and then boosted, plus the evolution of the virus since its late 2019 debut, the vaccines aren’t preventing infection as well as they once did.

Still, the vaccines continue to perform well, preventing the worst outcomes — ending up in the hospital, on a ventilator and death — which many infectious disease experts say should be the goal of the U.S. vaccination effort.

“This Omicron and its son of Omicron, BA.2, are so highly contagious that they can still infect you despite the fact that you have been vaccinated and boosted,” Schaffner said. “For the average person, that means you will have few symptoms or perhaps no symptoms at all. You will not get seriously ill.”

Layers of protection help lower risk.

Gridiron dinner guests were required to show proof of vaccination to attend. But the accumulation of positive tests after the dinner — including Attorney General Merrick Garland, Commerce Secretary Gina Raimondo and Reps. Adam Schiff (D-Calif.) and Joaquin Castro (D-Texas) — highlight that vaccination is just one way to counter Covid’s risks.

Another approach to mitigating the risk of having your party turning into a superspreader event is to require rapid Covid testing on the day of the gathering, Schaffner said. Tests weren’t required to attend the Gridiron dinner.

While at-home tests are not as sensitive as polymerase chain reaction, or PCR, tests analyzed in a lab, they work well at detecting when someone has a high viral count, which could be when they’re most contagious.

“Obviously, this virus also attended the event and was spread, and consequently made several people sick,” Schaffner said.

Still, the lack of reports of serious illness among officials who have contracted Covid “means the vaccines are doing their job,” he said.

Indoor events with meals have posed infection risks throughout the pandemic.

Eating, talking loudly and even singing indoors have proven to greatly increase the risk of viral spread during the pandemic. At the Gridiron dinner, attendees sat together in close proximity for hours, eating, drinking, talking over each other — even joining hands at the end to sing “Auld Lang Syne.”

That scenario means infected individuals were “releasing lots of virus into the air,” said Marr. “And … given that we’ve seen a lot of cases out of here, it’s likely the ventilation was not sufficient.”

“It only takes one person” shedding a lot of virus to spread Covid, she said.

The particles people release into the air when they’re talking is similar to coughing, Marr added.

“Imagine all those people standing around coughing together in the room, and you can more easily imagine there could be lots of virus released into the air,” she said.

I was around an infected person for less than 15 minutes. Am I in the clear?

The 15-minute guideline CDC uses to define a “close contact” of a Covid patient — “someone who was less than 6 feet away from an infected person … for a cumulative total of 15 minutes or more over a 24-hour period” — is “somewhat arbitrary,” Marr said.

White House spokesperson Jen Psaki on Thursday said President Joe Biden’s interactions with Speaker Nancy Pelosi this week before the California Democrat announced her positive test fell under that threshold. However, Psaki said the White House goes “over and above” CDC protocols when it comes to who surrounds the president, ensuring anyone in close proximity to him is tested regularly.

Studies in restaurants and hospitals suggest that, “under the wrong circumstances,” transmission can happen within a few minutes, Marr said, situations that involve close talking or an infectious person releasing lots of virus into a poorly ventilated room.

“There is enormous variability in the amount of virus that people release into the air, so you could be standing next to someone for hours and not become infected, or it could happen in just minutes,” she said. “Another source of variability is the exposed person’s immune response.”

What if you’re not ‘average?’ Or what if you are but really don’t want to catch Covid?

Any person 65 and older — or of any age who is immunocompromised or has an underlying condition that puts them at risk of severe Covid — must “think carefully” about large indoor events, Schaffner said. Several high-profile government officials — from Biden to Pelosi to chief medical adviser Anthony Fauci — fall into that category.

The FDA and CDC recently authorized a second booster dose of the Pfizer or Moderna vaccine for Americans 50 and older, as well as most immunocompromised individuals. Biden received his second booster on March 30.

Another mitigation strategy is to wear a mask — particularly a high-quality one, like an N95 or KN95 — to such an event as an extra layer beyond vaccination to lower the chances of infection.

Increasing the ventilation or air filtration in an event space, whether by keeping doors and windows open or setting up portable air cleaners “can make a surprisingly large difference,” Marr said, especially if you don’t want to reduce the number of invitees or institute a mask requirement.

A combination of approaches — say, vaccination and testing requirements with masks optional, or mandatory masking and vaccination without the need to show proof of negative test — can be used to help lower, but not eliminate, risk, Schaffner said.

“People who are either in the government in Washington or who are elected representatives, so much of that activity has to do with interpersonal interactions,” Schaffner said. “And so I think people in those circumstances really have to think about it carefully, and I would certainly say, as a minimum, be fully vaccinated.”



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