Shortly after the problems became apparent in early February, the Food and Drug Administration sent Timothy Stenzel, chief of in vitro diagnostics and radiological health, to the CDC to investigate what was going wrong. According to the Times, he found a lack of coordination and inexperience in commercial manufacturing.

Problems that led to the contamination included researchers coming and going from labs working on the test kits without changing their coats and researchers sharing lab space to both assemble test components and handle samples containing the coronavirus.

The CDC said in a statement Saturday to the Times that the agency “did not manufacture its test consistent with its own protocol.” Though the CDC appeared reluctant to admit contamination was at the root of the problem, the Times noted that in a separate statement the CDC seemed to acknowledge such problems, saying the agency has since “implemented enhanced quality control to address the issue and will be assessing the issue moving forward.”