Another variant of COVID-19 has been detected in samples from residents of Chittenden and Franklin counties, the Vermont Department of Health announced Thursday.

The B.1.429 strain from California is one of the “variants of concern” scientists have identified in locations around the world.

This particular variant is the second known to have found its way to the Green Mountain State. The United Kingdom mutation, also known as B.1.1.7, was first detected in a sample from a Chittenden County resident on March 8. Traces of the UK variant were found in Burlington wastewater samples back in February.

The variants of concern also include mutations first identified in Brazil, South Africa and New York. The mutations are more contagious and in some cases more deadly.

Ninety-eight samples taken from people who had already tested positive for COVID-19 were sent for testing to the Massachusetts Public Health Laboratory, Molecular Diagnostics and Virology program. Of that number, three were found to be the B.1.429 strain and eight were the B.1.1.7 variant.

Virus mutations are common, and the health department has anticipated the arrival of variants since January, advising that Vermonters should assume that the mutated versions of the coronavirus were already in circulation.

While Vermont has avoided the high hospitalization and mortality rates experienced in other states, case rates continue to be significantly higher than a year ago.

Dr. Mark Levine, the state’s health commissioner, said in a statement that the variants “can move more easily from person to person.”

“This is setting us up for a race of sorts between the presence of strains of a highly contagious virus, our rapidly progressing vaccination program, and the need for each of us to continue to focus on prevention and getting tested,” he said.

Levine urged Vermonters to “double down on efforts to prevent spreading the virus.”

Levine also urged individuals with symptoms to stay at home, skip events and avoid the workplace.

“Testing as early as possible is important for your health and the people around you,” he said. “Remember that symptoms can sometimes be mild, such as a headache, cough, fatigue or a runny nose. So, if you have even just one of these symptoms, it’s best to get tested, and to avoid going to work, school or other places until you receive a negative result.”