The U.K. COVID-19 strain has officially arrived in Pennsylvania, but health officials say it has likely been here a while.

“We'll be watching that very, very closely,” said Dr. Rachel Levine, Pennsylvania Secretary of Health. “That is not unexpected, that we would see cases of the variant.”

The first confirmed case of the U.K. COVID-19 strain, also known as the B.117 variant, was announced Thursday. Around five other states have reported cases of the variant in their borders.

According to the Centers for Disease Control and Prevention, the U.K. variant was first detected in September 2020 in England.

“This variant seems to spread more easily and quickly than other variants,” said the CDC's website. “Currently, there is no evidence that it causes more severe illness or increased risk of death.”

In an interview with Bloomberg, Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said he would not be “surprised” if the U.K. strain has been in the U.S. since before its first case was detected.

“It's not proven, but I wouldn't be surprised,” he said.

Levine agreed with this sentiment in an unrelated news conference Thursday. She said the identification of the variant relies on sending a sample for genetic testing. She said COVID-19 tests will test positive for the U.K. strain, but tests currently do not indicate strain-type.

“We are sending samples in a regular basis from our lab in Exton (Chester County) as well as other labs in PA to the CDC for this genetic analysis,” Levine said. “We will be working on developing the protocols to actually do that genetic analysis right here in our lab in Exton.”

On Thursday, 63 county residents were confirmed to have COVID-19 and nine residents were reported dead due to the virus, according to an update by the Department of Health.

Since the beginning of the pandemic, 6,854 residents have tested positive for COVID-19 and 225 residents have died due to the virus.

Statewide, the department reported 9,698 new confirmed cases and 265 new deaths. The state also reported it has administered 157,229 vaccines as Phase 1A of its distribution plans continue.

Levine has remained optimistic about the speed of distribution, and she noted the efficiency of the vaccine even in dealing with the newly recorded U.K. variant.

“Vaccine experts believe there will be no difficulty with the vaccine producing an immune response that will be able to prevent this strain,” she said. “There's every reason to believe that the vaccine will prevent this strain.”