People failing to wash their hands after going to the toilet, rather than undercooked meat or other food, is behind the spread of antibiotic-resistant E. coli, according to new research.

Humans and animals carry E. coli bacteria in the gut. It is usually harmless, but some strains cause food poisoning, others cause urinary tract infections (UTIs), and the most dangerous lead to bloodstream infections.

E. coli has become more antibiotic resistant over the past 20 years.

Strains with Extended Spectrum Beta-Lactamases (ESBLs) enzymes destroy penicillin and another antibiotic called cephalosporin.

Scientists have now discovered that the likeliest route of transmission for ESBL-E. coli is directly from human to human, "with faecal particles from one person reaching the mouth of another."