Gene discovered in Georgia water a possible global threat

A gene that causes bacteria to be resistant to one of the world's most important antibiotics, colistin, has been detected in sewer water in Georgia. The presence of the MCR-9 gene is a major concern for public health because it causes antimicrobial resistance.

Researchers from the University of Georgia's Center for Food Safety (CFS) collected sewage water from an urban setting in Georgia to test for the MCR gene in naturally present bacteria. Led by College of Agricultural and Environmental Sciences assistant professor Issmat Kassem, whose research focuses on MCR's presence around the world, the team was surprised at how quickly they detected MCR – they found evidence of the gene in the first sample they took.

Kassem said that demonstrates that the gene is becoming established in the U.S. The bacteria where the gene was found, Morganella morganii, added further concern for Kassem. This marked the first time that MCR was found in M. morganii, which is problematic because it is a bacteria not often tested by researchers. This means that the problem could be considerably more widespread than initially thought.

Colistin is banned in the U.S. for use in food animals and it was previously thought that this measure would help slow the spread of antimicrobial resistance to colistin in the country. However, MCR can be spread through global travel and the import of foods from other countries. Results of the CFS study prove that the U.S. is no less susceptible to the threat than other nations around the world.