U.S. workers treated for anthrax exposure

Some workers at the Centers for Disease Control and Prevention may have been accidentally exposed to dangerous anthrax bacteria earlier this month, the U.S. agency said Thursday.

CDC officials say the risk of infection seems very low, but that about 75 staff members were being monitored or given antibiotics as a precaution.

“Based on the investigation to date, 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,” a statement from the agency says.

A safety problem at some of its labs in Atlanta was discovered last Friday, and some of the anthrax may have become airborne in two labs the previous week, the statement says.

The safety lapse occurred when a high-level biosecurity lab was preparing anthrax samples for use at lower-security labs that were researching new ways to detect the germs in environmental samples.

The higher-security lab used a procedure that did not completely inactivate the bacteria.

Workers in three labs who later came into contact with these potentially infectious samples were not wearing adequate protective gear because they believed the samples had been inactivated. Procedures in two of the labs may have aerosolized anthrax spores.

Live bacteria were discovered last Friday on materials gathered for disposal.

Anthrax is a deadly infection caused by the spore-forming bacillus anthracis, more often found in cows and sheep than humans.

The bacteria can infect the lungs or digestive tract, though most infections start when the bacterial spore penetrates the skin. It isn’t contagious.

People exposed to it are typically treated with antibiotics.