President Donald Trump’s Health Secretary, Robert F. Kennedy Jr., also described political violence as “wrong” and said his job is to protect employees.

On Sunday, CNN reported that the CDC held a video conference with approximately 800 staff members to discuss the traumatic event and allow them to ask questions. Staff said they felt like "sitting ducks" as bullets whizzed just over their cubicle walls and they dove for the floor.

CDC staffers are voicing frustration over RFK Jr.’s past vaccine comments, following Friday’s shooting at the agency’s headquarters in Atlanta that left one officer dead.

The US Department of Health and Human Services (HHS) plans to cancel $500m (£376m) in funding for mRNA vaccines being developed to counter viruses that cause diseases such as the flu and Covid-19.

Adams, who served as surgeon general during the first Trump administration, said Kennedy's assertions about the efficacy of mRNA vaccines are "simply not true."