DES MOINES — Iowa health officials on Thursday confirmed the first case of the omicron coronavirus variant in the state.

The case involves an unvaccinated person under the age of 18 who lives in Black Hawk County in eastern Iowa. The individual has no symptoms but because of travel exposure the family sought testing based on public health guidance, health officials said.

Omicron has been identified in at least 19 states. Scientists are working to determine 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.

“There is emerging evidence that a booster dose of vaccine offers protection against omicron, which is great news,” said IDPH interim Director Kelly Garcia in a statement. “Vaccinated Iowans who have not yet received a booster should do so as soon as possible.”

More than a third of Iowans remain unvaccinated and the Centers for Disease Control and Prevention says 57.5 percent of the population is fully vaccinated, placing the state 24th in the nation.

Iowa is experiencing a high rate of spread of COVID-19 in all 99 counties.