Virus Outbreak J&J Vaccine

FILE - In this April 8, 2021 file photo, the Johnson & Johnson COVID-19 vaccine is seen at a pop up vaccination site in the Staten Island borough of New York. With a green light from federal health officials, several states resumed use of the one-shot Johnson & Johnson coronavirus vaccine on Saturday, April 24. Among the venues where it's being deployed is the Indianapolis Motor Speedway, where free vaccinations were available to anyone 18 or older.

Three reports of people sustaining blood clots after receiving the Johnson & Johnson vaccine have been made in Colorado, a state spokesperson said Thursday, representing a tiny fraction of the more than 139,000 doses that have been administered statewide.

Five total reports of "blood clotting events" were reported to the federal Vaccine Adverse Event Reporting System, said Brian Spencer, spokesman for the state Department of Public Health and Environment. Three of those were made after the patients received the Johnson & Johnson vaccine. Those three represent 0.002% of doses administered in Colorado.

It's unclear if the vaccine caused the clotting in those three patients. Spencer said the Centers for Disease Control and Prevention handled the investigations "and makes the determination of whether reported blood clotting events" are related to the vaccine. He said it was not likely all three will meet that definition.

The CDC did not return a previous request for comment about reports of clotting in Colorado. Centura said earlier this month one person who'd received the Johnson & Johnson dose had been hospitalized, but the hospital system has not released any more information. A Centura spokeswoman did not provide comment Wednesday.

Administration of the Johnson & Johnson vaccine was halted for two weeks beginning in mid-April after several cases of clots, representing a tiny slice of vaccine recipients, reported a unique form of blood clots. The pause ended late last week, after a federal review panel gave the dose the all clear. 

The state quickly followed federal regulators' approval and has begun administering Johnson & Johnson doses again.