Water taps in hospitals are full of bacteria, increasing the risk of infection in immunocompromised patients, according to a new study published in Infection Control and 
Hospital Epidemiology.
Researchers monitored bacterial growth in cold and hot water samples at two tertiary care hospitals over the course of a year, from faucets used for hand washing, surgical washing and cleaning of medical equipment. Study authors, led by Maria Luisa Cristinia, Ph.D., then compared the samples taken from faucets with aerators to those from deeper in the plumbing system.
The total microbial load of the water samples was as much as 10 times greater with aerators than after sterilization, with opportunist microorganisms like Legionella and Acinetobacter much more common at the faucet level than deeper in the system. The temperature of the hot water samples, researchers noted, were below the minimal temperature necessary to stem Legionella growth.
"Aerators are a reservoir for drug-resistant bacteria and a source of infection for patients at risk," said Cristina in a statement. "Safe water is vital to ensuring patient safety where waterborne infections increase morbidity, mortality, treatment costs, compensation claims and prolong hospital stays."
Solutions to the problem are elusive because routinely cleaning all aerators and drains thoroughly enough to remove all potential pathogens would be a "Sisyphean task with unclear payoffs," according to Tara Palmore, M.D., of the National Institutes of Health (NIH).
"Hospitals tend to have large, complex waterworks with low-flow areas that produce stagnation and biofilm formation; hot and cold water temperatures that are not well regulated may be ideal for bacterial growth," Palmore wrote in a commentary accompanying the study.
In the meantime, there may be alternative hand-hygiene strategies that make the faucets less of an issue. A study published in October found that cleaning hand sanitizer dispensers and giving workers personal bottles of sanitizer caused a marked decrease in bacterial infections, FierceHealthcare previously reported.
To learn more:
- read the study
- here's the announcement
- check out the commentary