DENVER (AP) — Colorado became the third U.S. state to detect a case of the omicron variant in a woman who had recently traveled to Africa, state health officials announced Thursday.
The Colorado case comes after two other confirmed omicron variant cases were found in California and Minnesota.
Officials in Colorado detected the new case in a woman who is a resident of Arapahoe County, an area just southeast of Denver. She recently traveled as a tourist to several countries in Africa, including South Africa, the state health department said in a statement.
The woman is fully vaccinated, but had not received her booster shot yet, they said.
She is experiencing mild symptoms, health officials said. The woman’s close contacts in Colorado have tested negative, they said.
The Colorado health department is working with the U.S. Centers for Disease Control and Prevention to investigate and coordinate contact tracing efforts domestically and internationally.
Given the realities of international travel, scientists said it was inevitable that the omicron variant would be discovered in the U.S., and they believe it may have been spreading in the country before it was detected.
Scientists monitor variants and the coronavirus’ evolution through genetic tests that are separate from the kinds of tests used to determine whether someone has COVID-19. This genetic sequencing allows scientists to monitor how the virus changes over time.
The coronavirus is continually evolving, but most mutations are inconsequential. At this point, scientists are trying to figure out whether omicron spreads more easily or causes more severe disease than the delta variant that now dominates in the U.S. They are also studying how well the current vaccines work against it.