As many as 86 Atlanta-based workers for the Centers for Disease Control and Prevention may have been unintentionally exposed to anthrax, the agency says. This includes people who have come forward since the announcement Thursday, saying they were in the area during the time of exposure.
The workers are being monitored or provided antibiotics.
"Based on most of the potential exposure scenarios, the risk of infection is very low," the agency said in a statement.
"CDC believes that other CDC staff, family members, and the general public are not at risk of exposure and do not need to take any protective action."
As of Thursday afternoon, the agency's Occupational Health Clinic had seen 54 employees identified to have been in the labs or hallways at the time of exposure, according to CDC spokesman Tom Skinner.