Farmed fish are at increasing risk of disease due to global warming, a study has found for the first time.

Researchers discovered that as oceans and freshwater sources heat up, conditions become more favourable for bacteria, leading fish farmers to use increasing amounts of antimicrobial drugs to fight disease in their stock.

But large quantities of antimicrobial agents in fish farms has led to an increase in drug-resistant bacteria.

“Resistant bacteria in aquaculture can either spread or transmit their resistance genes to non-resistant bacteria that infect humans, thus causing diseases that are difficult to treat in both animals and humans,” Samira Sarter, a microbiologist who was part of the study, told Science Daily.