Using disinfectants could cause bacteria to become resistant to antibiotics as well as the disinfectant itself, according to research published in the January issue of Microbiology. The findings could have important implications for how the spread of infection is managed in hospital settings.
Researchers from the National University of Ireland in Galway found that by adding increasing amounts of disinfectant to laboratory cultures of Pseudomonas aeruginosa, the bacteria could adapt to survive not only the disinfectant but also ciprofloxacin - a commonly-prescribed antibiotic - even without being exposed to it. The researchers showed that the bacteria had adapted to more efficiently pump out antimicrobial agents (disinfectant and antibiotic) from the bacterial cell. The adapted bacteria also had a mutation in their DNA that allowed them to resist ciprofloxacin-type antibiotics specifically.
P. aeruginosa is an opportunistic bacterium that can cause a wide range of infections in people with weak immune systems and those with diseases such as cystic fibrosis (CF) and diabetes. P. aeruginosa is an important cause of hospital-acquired infections. Disinfectants are used to kill bacteria on surfaces to prevent their spread. If the bacteria manage to survive and go on to infect patients, antibiotics are used to treat them. Bacteria that can resist both these control points may be a serious threat to hospital patients.