Lifestyle Health Healthy People with Booster Shots Not Likely to Get Severe Infections from Omicron, Data Show While healthy, boosted individuals appeared less likely to contract severe cases of COVID-19 with the omicron variant, older people or those with underlying conditions may still be at risk By Greta Bjornson Greta Bjornson Twitter Digital News Writer, PEOPLE People Editorial Guidelines Published on December 28, 2021 12:57 PM Share Tweet Pin Email Photo: Getty Images Healthy individuals who have received a booster shot are less likely to suffer severe infection from the omicron coronavirus variant, new studies suggest. Medical experts told The Washington Post that research has shown omicron infections have "less severe effects than the delta variant." Omicron, which was first discovered in the U.S. earlier this month, is much more contagious than previous variants, but appears to have lower rates of hospitalization. James Musser, chair of pathology and genomic medicine at the Houston Methodist hospital system, told the Post that around 15 percent of "symptomatic individuals" have been hospitalized for COVID-19 in the hospital system, marking a 70 percent drop in hospitalizations compared to those infected with delta. Dr. Fauci Recommends Vaccine Mandate for Domestic Flights, But Says It's Not Expected to Happen "What is absolutely clear is there is lower rate of hospitalization with our omicron patients in our hospital system," Musser told the Post. "That does not necessarily mean that this variant is quote-unquote 'less virulent.' The jury's still out on that. What we know now is that … if you are immunized and, more importantly, if you are boosted, you're going to stay out of substantial trouble." Patients infected with omicron have seen decreased rates of hospitalization abroad, as well. Data from England studied by Imperial College London scientists showed that patients infected with omicron are 15 to 20 percent less likely to land in the emergency room than those with delta, per the Post. The CDC has also stated that "early data" suggests "Omicron infection might be less severe than infection with prior variants," but the agency cautioned, "reliable data on clinical severity remain limited." While boosted individuals appear less likely to contract serious infections from the omicron variant, medical experts still cautioned to the Post that those who remain unvaccinated are at risk of severe illness. COVID-19 testing. Getty COVID-19 Hospitalizations Among Children Surge in New York Older populations and those with underlying conditions could be at higher risk for severe illness, Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota, told the Post. "Have you previously had infection? Were you vaccinated? How many doses of vaccine, and was it more than six months ago?" Osterholm said. "So in some ways this is almost like a calculus problem. It's got a lot of moving parts to it and we're trying to figure it out." The latest data comes as omicron is surging in the U.S. During a Sunday appearance on ABC News' This Week, leading infectious disease expert Dr. Anthony Fauci described the variant as "extraordinarily contagious," adding, "It's just outstripped even the most contagious of the previous ones, including delta. There's no argument on anybody's part about that." Although the variant appears to pose less of a threat to healthy, boosted individuals, Fauci told the Post that Americans should try to remain cautious to avoid overwhelming the health care system. "We're going to have a real challenge to the health-care delivery system — namely the number of beds, the number of ICU beds and even the number of health care providers," he said. "Even vaccinated people are getting breakthrough infections. So if you get enough nurses and doctors infected, they are going to temporarily be out of action. And if you get enough of them out of action, you could have a double stress on the health care system." Breakthrough cases — COVID-19 infections that occur in people who have been fully vaccinated against the virus — are possible and expected, as the vaccines are not 100% effective in preventing infections. Still, vaccinated people who test positive will likely be asymptomatic or experience a far milder illness than if they were not vaccinated. The majority of deaths from COVID-19 — around 98 to 99% — are in unvaccinated people.