The Centers for Disease Control and Prevention (CDC) conducted an internal investigation after an agency whistleblower claimed they were using the wrong Zika test, according to documents released Tuesday. The documents reveal that Robert Lanciotti, chief of the CDC lab responsible for developing tests to diagnose viral diseases, was demoted this May after raising concerns about the CDC’s recommendation to use a new test for diagnosing Zika. The centers used a test that was “substantially less effective than another established test, [Lanciotti] said, and misses nearly 40 percent of Zika infections,” according to The Washington Post. Lanciotti was reinstated to his lab position in July after filing a whistleblower retaliation claim, according to documents made public by the Office of Special Counsel on Tuesday. An internal investigation found that the CDC acted “reasonably” and that heeding conflicting test data from other state health labs could have created uncertainty during a public health crisis. Releasing the incongruous data would have created “considerable confusion during an ongoing emergency response,” CDC investigators stated.