While investigating the anthrax missteps, the CDC learned of another glaring mistake involving a different set of scientists who had cross-contaminated a benign strain of bird flu with a deadly ...

The CDC is strengthening lab-safety rules following 3 scares in 3 months. ... One incident in 2006 occurred at the same lab where the recent problem with anthrax samples occurred.

Even with antibiotic treatment, anthrax has a fatality rate of 28% to 45%, depending on the type of exposure, according to information on the CDC's website.

The CDC is still investigating the exposure and has decontaminated lab and hallway areas that were exposed, according to a statement. Anthrax spores can be breathed in or ingested through ...