The more highly transmissible COVID-19 variant first detected in the United Kingdom has infected three people in Alabama, state health officials said Wednesday.

The variant was found in two children and one adult, the state heath department said in a statement. Two cases are in Montgomery County and one is in Jefferson, the statement said.

The variant is thought to be more contagious, although health officials say it has not definitively been shown to be more virulent. It also has been detected in at least 24 other states, including Florida, Georgia, North Carolina and Tennessee. The variant was first detected in the U.K. late last year.

“Given that the U.K. variant has already been detected in most of the states that surround Alabama, it is not surprising that it has finally been detected here,” said State Health Officer Scott Harris.

“The U.K. variant is not known to further increase the risk of serious illness or death beyond our original strain, but it is easier to transmit, and so we are simply encouraging Alabamians to continue those practices that keep everyone safe, such as masking, social distancing and hygiene.”

Infectious disease experts and the Centers for Disease Control and Prevention have indicated that the current vaccine should be effective against the U.K. strain, but it is still being studied, state health officials said.