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Omicron variant: Emory experts discuss latest news
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Gana Ahn

Dr. Carlos del Rio of Emory University advises what type of mask to use. Is N95 the way to go? Or is cloth OK?

Amid massive spikes of COVID-19 infections caused by the Omicron variant, public health agencies around the world are revising their guidance for preventing transmission. In the U.S., health officials have amended recommendations for quarantine, isolation and booster shots in response to the surge.

Jodie Guest, PhD, professor and vice chair of the department of epidemiology at Emory’s Rollins School of Public Health, and Carlos del Rio, MD, distinguished professor of medicine, epidemiology and global health and executive associate dean of Emory University School of Medicine at Grady Health System, teamed up to discuss the recent changes and the latest news related to the Omicron variant.

Their conversation is part of an online video series hosted by Guest, who also leads the Emory COVID-19 Outbreak Response Team, answering questions related to the COVID-19 pandemic. Watch the full conversation between Guest and del Rio here.

Q: What is the current state of the pandemic in the U.S.?

A: During a two-week period encompassing the Christmas and New Year’s holidays, cases of COVID-19 increased by more than 254%. The Centers for Disease Control and Prevention (CDC) estimates that Omicron accounts for approximately 95% of those cases. According to Guest, 97% of U.S. counties are now considered areas of high community transmission.

“On Jan. 4, more than 880,000 people tested positive for COVID-19 in the United States, with a seven-day average of over 550,000 new cases a day,” says Guest. “To put this in perspective, this is two times our peak last January, and three times our peak from the Delta surge this past fall.” 

By Jan. 11, the number of people hospitalized with COVID-19 reached a record high of more than 145,000, and deaths related to COVID-19 averaged around 1,600 per day.

Q: What symptoms are associated with the Omicron variant?

A: “This strain appears to cause a very different syndrome,” del Rio says. “There’s some laboratory data to suggest [Omicron] is probably not as good as previous strains at infecting the lower respiratory tract, so you get less pneumonia, less severe lower respiratory disease. But it’s very good at infecting the upper respiratory tract, so you get more of a bronchitis, a laryngitis, or an upper respiratory illness very much like a head cold.”

“You also get a lot of people complaining about tingling in the throat as part of their symptoms,” he adds. “Interestingly, I’ve yet to see somebody with Omicron present with loss of sense of taste or smell, which was so characteristic in the past.”

While infections of the throat and upper respiratory tract may cause milder disease in adults, they tend to cause more severe illness in kids. “Children are not very good at handling upper respiratory infections. Therefore, hospitalizations in children are actually higher than they’ve been, because children are coming in with what we call ‘croup,’ which is this inability to breathe well,” del Rio says.

Q: How is the surge of Omicron infections affecting hospitals?

A: “We have more patients than we’ve ever had before at my hospital, Grady Hospital,” del Rio says. “But when I look at the patients, about 20 to 30% are people who are coming in with other diseases, or in which COVID has exacerbated the other disease.”

The hospital tests all patients upon arrival, del Rio explains, so some patients who are not sick because of COVID-19 may still be identified as positive cases. “They have another disease, and COVID happens to be an associated condition,” he says. While these patients may not require intensive care related to COVID-19, they strain hospitals’ capacity to isolate contagious individuals.

del Rio says the remaining patients he sees hospitalized with COVID-19 are primarily unvaccinated individuals. “Some of them are actually ending up in the ICU. There are not many ending up in the ICU, but clearly all of them are those individuals who are unvaccinated, or who are not boosted and have an underlying condition.”

Staffing shortages are also stretching hospitals to their limits. Many health care workers have acquired COVID-19 in their communities and are unable to report to work.

“So, part of the problem in ICUs is not necessarily lack of capacity, but actually lack of staff to be able to take care of the patients appropriately,” del Rio emphasizes. “It’s a very complicated situation.”

Q: How soon do symptoms appear after exposure to Omicron?

A: “It’s very clear that the time between exposure and disease is much shorter,” del Rio says. With previous strains, the onset of symptoms could occur anywhere between two to 14 days. With the Omicron strain, “it’s probably one to three days, at most.”

“In some ways, this feels like some good epidemiology data if there is less potential for asymptomatic spread,” Guest says.

However, this truncated timeline complicates the efforts of contact tracers. “You cannot do contract tracing for this disease. It just doesn’t work, you can’t do it fast enough,” del Rio says. Therefore, testing regularly and at the first sign of symptoms remains critical.

Individuals who experience symptoms and who test positive should isolate as soon as possible. “Because Omicron is so incredibly transmissible, we’re seeing that if one person in a house gets it, everyone gets it — unless they are isolating really fast,” Guest says.

Q: What are the latest recommendations for quarantine after exposure to COVID-19?

A: On Dec. 27, 2021, the CDC updated its quarantine and isolation guidance.

“The quarantine guidance differentiates by vaccination status,” Guest says. Those who are unvaccinated or who are vaccinated but overdue for a booster should quarantine at home for five days following exposure to a person with COVID-19. They should wear a well-fitted mask when around others in the home.

On day five of quarantine, they should test for COVID-19. If positive, they should move to isolation. If negative, they may exit quarantine and adhere to strict mask wearing for another five days.

Individuals who are boosted do not need to quarantine at home if they are exposed to COVID-19, but they do need to adhere to ten days of strict mask wearing when around others. They should also test on day five and move to isolation if they test positive.

“It’s saying what we all want to hear, which is if you’re vaccinated and boosted, you’re more protected,” del Rio says of the guidance. “You don’t need to quarantine and you are much safer if you’re vaccinated and boosted than if you are not.”

Q: What are the latest recommendations for isolation after testing positive for COVID-19?

A: If a person has symptoms or tests positive for COVID-19, they should enter a period of isolation. These individuals should isolate for five days and wear a well-fitted mask when around others in the home.

The CDC states that asymptomatic individuals may end isolation a full five days after a positive test. Symptomatic individuals may end isolation after five days if they have been fever-free for 24 hours and their symptoms are improving. Individuals who have symptoms at day 5 should continue to isolate for 10 days. 

“It is only between the third and fourth day that you’re highly contagious,” del Rio says. “By day five or six, only about 20% or so of individuals are still contagious. A great majority are not.”

All individuals who have tested positive for COVID-19 should continue to wear a well-fitted mask when around others, avoid travel and avoid being around high-risk individuals for at least 10 days.

The CDC also states that those who have access to antigen tests may choose to test at home around day five of isolation. If positive, the individual should continue to isolate until day 10. If negative, the individual may end isolation and continue strict mask wearing at home and in public until day 10.

Both experts also like the isolation guidance issued by the United Kingdom. “The U.K. guidance cut the isolation from 10 to seven days and said to get a test at day six and get a test at day seven. And then if you’re negative in both, you can come out of isolation,” del Rio says.

Q: How should I test for COVID-19?

A: PCR tests, which consist of a nasal swab at a testing clinic, are very good at detecting particles of COVID-19. Because they are so sensitive, they are best suited for diagnosing new infections. 

PCR tests are not recommended for determining whether a person is still contagious after a period of isolation, because they may return a positive result for a long time after an individual is no longer infectious.

Rapid antigen tests, which may be self-administered at home, are less sensitive than PCR tests. “That’s the kind of test that we really want to use if you’re in isolation,” Guest says, because antigen tests can indicate whether a person is currently contagious.

Because antigen tests are less sensitive than PCR tests, it is important to use them in a sequential manner. For example, del Rio says that his family members tested twice before gathering for Christmas — once 24 hours prior the event, and once immediately before gathering. “If you do double testing,” he says, “the chances of somebody who’s going to be infected and not picked up by the test dramatically decreases.”

Q: What are the latest changes to recommendations for COVID-19 booster shots?

A: “On Jan. 3, the FDA expanded the emergency use authorization for Pfizer’s COVID-19 vaccine booster to children ages 12 to 15,” Guest says. Since then, the CDC has reviewed these data and supported this recommendation.

The FDA and CDC also support third doses of COVID-19 vaccines (which are different from boosters) for children ages 5 to 11 with certain immunologic conditions. Additionally, both agencies recommend that people who received a primary vaccination series of the Pfizer vaccine now receive an mRNA booster five months after that series, rather than the previously recommended six months.

Individuals who are vaccinated but not boosted and had COVID-19 should receive a COVID-19 booster shot once they have completed a period of isolation and are free of symptoms, Guest adds.

Q: Are fourth boosters on the horizon in the U.S.?

A: “I hope not,” del Rio says. “We have about 60 to 70 million Americans who are yet to be vaccinated. The booster I need is for those that haven’t been vaccinated to be vaccinated. We don’t end [the pandemic] by giving fourth and fifth and sixth boosters to people who have already been vaccinated.”

“What I would love to see is a company start working on is a broader vaccine, more of a pan-coronavirus vaccine,” he continues. “This is a global pandemic. We’ve got to get people vaccinated globally, and we cannot continue boosting this way, because this is going to really increase health inequities and that’s something we need to really keep our eye on.”

Q: When might Omicron infections peak in the U.S.?

A: “My prediction is that we’re probably going to peak somewhere between the third week of January and the first or second week of February, and then we’re going to start coming down from there,” del Rio says, noting that Christmas and New Year’s celebrations likely increased transmission of Omicron.

“My concern, though, is that we’re going to be having way over a million new infections per day over the next several weeks,” he continues. “At this rate we may actually really be able to reach herd immunity, because we’re going to get so many people in the population infected that at some point in time this may be sort of the beginning of the end of the pandemic, at least in this country. Because Omicron is really going to infect pretty much everybody who hasn’t been infected so far.”

“What I want to remind people is: this is not something you want to get,” del Rio stresses. COVID-19 infection can cause life-threatening and long-term illness. Mitigation measures remain important to protect ourselves and the most vulnerable members of our communities, such as immunocompromised individuals and children who are ineligible for vaccines.

“We want to slow down transmission, but we also want to slow down any new variants that are coming,” Guest adds. “And every single case of COVID-19, particularly among those who are unvaccinated, is a place where this virus can mutate further — and it would be great if Omicron was the last variant we were to see from this virus.”

Q: What kinds of masks are recommended to prevent the spread of Omicron?

A: “I am gravitating towards the mask that fits my face particularly well and one that is easy for me to teach in and speak in without disrupting the way I sound,” Guest says. Her preferred mask is a KF94.

del Rio recommends wearing a well-fitted and multi-layered mask, but he does not suggest the general public wear fitted N95 masks. “A fitted N95 is simply very hard to use,” he says. “But if your face fits well in a KN95, that’s a good mask. Just be sure that it’s a good mask, because if you bought them on the internet, there’s a lot of fake masks out there.”

“Wear a mask indoors when you’re in public,” Guest stresses. “There’s almost nowhere in the United States where that is not currently called for.”