The Minnesota Department of Health (MDH) worked with local, state and federal partners this week to investigate an abnormal test result from routine air monitoring conducted in the Twin Cities metropolitan area.

Bacillus anthracis bacteria Image/CDC
Bacillus anthracis bacteria

Testing at one location in suburban Ramsey County Wednesday yielded a result consistent with the bacteria that can cause anthrax infection (Bacillus anthracis). However, there are no reports of human or animal illness and extensive additional sampling has been negative.

“Based on what we know now, this does not appear to present a threat to public health,” Minnesota State Epidemiologist Dr. Ruth Lynfield said. “The information we’ve gathered is consistent with a naturally occurring, low-level detection.”

After receiving the initial laboratory result, MDH conducted follow-up testing at the location and other sites in the Minneapolis-St. Paul area. All of the additional tests were negative. Communication with healthcare providers, clinical laboratories and veterinary care providers found no evidence of anthrax infections in people or animals.

The Twin Cities is one of 30 U.S. metropolitan areas participating in a federal early warning system designed to quickly detect certain substances in the air. The BioWatch program focuses on substances that could be released intentionally to cause harm, though some – like Bacillus anthracis– can also be found naturally in the environment. When a substance is detected at a monitoring station, the next step is to evaluate whether it may be the result of a natural occurrence or an intentional act. Based on the information gathered to date, this case is consistent with a natural occurrence.

MDH will continue to work with public health, law enforcement, health care providers and others to closely monitor the situation and will alert the public of any developments that suggest a health risk.