The first case of the Omicron variant of COVID-19 was detected in Massachusetts on Saturday.

Fenway Park will become the second mass vaccination site in the state, joining Gillette Stadium in Foxborough, which first began offering shots mid-January. Vaccines will be distributed at Fenway Park from Feb. 1 until baseball season starts in early April.

Cases have increased dramatically since the summer, when Mass. was reporting fewer than 500 a day.