The CDC is under fire for another potentially dangerous mistake that scientists kept secret.
An internal investigation revealed a government scientist working at the headquarters in Atlanta accidentally mixed a deadly strain of bird flu, and then sent it to other labs back in January.
The lab worker reportedly realized a mistake was made, but didn't say anything. Fortunately, no one was infected, but scientists unknowingly worked with the dangerous mix for months before it was discovered.
CDC officials are calling the incident the most worrisome in a series of lab safety problems at the agency.
The same facility had an anthrax exposure scare in June that put more than 80 employees at risk to exposure.
Anthrax enclosed tubes were sent to lower security labs, but workers didn't follow proper safety procedures. They managed to disrupt the samples and remove the lids.
The FBI became involved in the internal investigation while the organization reviewed safety procedures with its employees.
More to see:
USDA cracks down on imports from foreign puppy mills
Brittney Griner, Glory Johnson: first comes love, then comes legal battle
McDonald's confronts its junk food image
Haves, have-nots divided by apartment poor doors