Flies may spread poultry farm bacteria

Johns Hopkins University scientists in Baltimore say they have found evidence houseflies collected near poultry farms may spread drug-resistant bacteria.

The researchers from the university’s Bloomberg School of Public Health said their findings demonstrate another potential link between industrial food animal production and exposure to antibiotic resistant pathogens.

Flies are well-known vectors of disease and have been implicated in the spread of various viral and bacterial infections affecting humans, including enteric fever, cholera, salmonellosis, campylobacteriosis and shigellosis, said lead author Jay Graham, who conducted the study as a research fellow at the school’s Center for a Livable Future. Our study found similarities in the antibiotic-resistant bacteria in both the flies and poultry litter we sampled. The evidence is another example of the risks associated with the inadequate treatment of animal wastes.

Although the scientists did not directly quantify the contribution of flies to human exposure, the results suggest flies in intensive production areas could efficiently spread resistant organisms over large distances, said Professor Ellen Silbergeld, senior author of the research.

The study that included Lance Price, Sean Evans and Thaddeaus Graczyk appears in the journal Science of the Total Environment.