KANSAS CITY – A recent study claims to confirm animal-to-human transfer of methicillin-resistant Staphylococcus aureus (MRSA).

Researchers used whole-genome sequencing to determine if drug-resistant bacteria are transmitted from animals to humans in two disease outbreaks that occurred on different farms in Denmark. Drug resistant bacterial infections are a serious public health issue that can have fatal consequences. MRSA can lead to debilitating skin and soft tissue infections, bacteremia, pneumonia and endocarditis.

The authors claim their findings show the MRSA strains studied were capable of animal-to-human transmission, which shows compelling evidence of livestock as a potential reservoir of antibiotic-resistant bacteria.

"We used whole genome sequencing to see if we could determine if the two disease outbreaks were caused by the same bacterium and to investigate if the pathogens were transmitted from animal to humans or the other way around," Mark Holmes, from the Univ. of Cambridge and the senior author on the paper, said in a statement. "At first glance, it seems reasonable to expect the same pathogen to be the source of the two outbreaks at the two geographically close locations. By looking at the single differences in nucleotides or SNPs in the DNA sequences of each isolate, it became obvious that two different strains of bacteria were responsible for the two disease outbreaks. In one case, the results also clearly showed that the most likely direction of transmission was from animal to human."

The findings were published in the March issue of EMBO Molecular Medicine.