How The Johnson & Johnson News Will Affect The Vaccine Rollout In Mass.

Massachusetts health officials have temporarily put on hold the use of Johnson & Johnson's COVID-19 vaccine, creating uncertainty over how fast the state can vaccinate residents.

The Centers for Disease Control and Prevention and the Food and Drug Administration are looking into reports that six people developed rare blood clots days after receiving the vaccine.

About 10% of the roughly 1.8 million people fully vaccinated in the Bay State have received the J&J vaccine. Just Monday, Gov. Charlie Baker said the single-dose vaccine was a key to accelerating the pace of vaccinations in the state.

Senior State House reporter Steve Brown joined WBUR's All Things Considered host Lisa Mullins to discuss the latest developments.