Officials also said the metro resident is isolating at home and that contact tracing is underway to identify those who might have come in close contact with him or her and who may be at risk of infection.

On Friday, state health officials confirmed they were notified of a separate resident who had recently returned from South Africa and who was in Georgia for two days before traveling to New Jersey, where the Georgia woman tested positive. She is fully vaccinated and was isolating in New Jersey.

Named after the 15th letter of the Greek alphabet, omicron was first reported to the World Health Organization from South Africa on Nov. 24. Two days later, the WHO labeled omicron a “variant of concern,” saying it was coordinating with a large number of researchers around the world to better understand it. They are studying whether it is more transmissible and if it causes more severe symptoms. The WHO has warned that “preliminary evidence suggests an increased risk of reinfection with this variant” in those who have already had COVID-19.

In addition to Georgia and New Jersey, omicron has been detected in 15 other states, according to The New York Times: California, Colorado, Connecticut, Hawaii, Louisiana, Maryland, Massachusetts, Minnesota, Missouri, Nebraska, New York, Pennsylvania, Utah, Washington and Wisconsin. The variant has also been detected in Australia, Botswana, Britain, Canada, Denmark, Germany, India, Israel, Norway, Spain, South Africa, Zambia and Zimbabwe as well as in travelers in numerous other countries, the Times reported.

The spread of omicron has prompted the United States and other countries to temporarily bar foreign travelers from South Africa and seven other African nations.

More than 1.2 million COVID-19 cases have been confirmed in Georgia, about 89,000 hospitalizations have resulted from those infections and more than 25,700 people have died from the disease in the state, Public Health Department figures show. Worldwide, the disease has killed more than 5.2 million people, according to Johns Hopkins University’s Coronavirus Resource Center.

Dr. Carlos del Rio, who teaches medicine, global health and epidemiology at Emory University, underscored that the metro Atlanta resident with omicron has developed only mild symptoms.

“If you are vaccinated and boosted and omicron gets you infected, but all you do is develop mild symptoms, I will take it, right?” he said. “I think vaccines are not going to be perfect in preventing infection, especially with this strain. They are going to be good, but they are not going to be perfect. And people are going to get infected. But if you get infected and you don’t end up in the hospital and you only have mild symptoms, it is OK.”

Omicron, he said, appears to be “fairly contagious,” and people who have had COVID-19 are not protected against it.

“If you are vaccinated, get boosted. If you haven’t been vaccinated, get vaccinated,” del Rio said. He added that just like with the delta variant of COVID-19, “the people who are going to get sick and the people who are going to end up in the hospital, are going to be the unvaccinated.”

All Georgians over the age of 5 are now eligible to be vaccinated. Booster doses are recommended for people 18 and older who completed their first series of vaccine at least six months ago.

As of Saturday, 198.6 million people in the United States had been fully vaccinated, and 45.3 million had received a booster dose, according to the Centers for Disease Control and Prevention.

“Vaccination is key to preventing further transmission of COVID-19 and helps prevent new variants like omicron from emerging,” Dr. Kathleen Toomey, DPH’s commissioner, said in a statement Sunday.

“It also is important to remember that even as omicron is emerging, we are still in the midst of a pandemic currently being fueled by the delta variant.”

A spokeswoman for Gov. Brian Kemp said Sunday the governor’s office is closely coordinating with public health experts.

“Like the Georgia Department of Public Health, we continue to encourage Georgians to talk to a trusted medical provider about the benefits of getting vaccinated,” Kemp spokeswoman Katie Byrd said.

AJC staff writer Greg Bluestein contributed to this report.

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