Well here's a study that will have you reaching for the antibacterial wipes and possibly vowing never to visit a play centre again.
New research, published in the American Journal of Infection Control, found "considerable microbial colonisation" in ball pits in paediatric physical therapy clinics, which are similar to those found in play centres.
"Ball pits are often contaminated with visible dirt, vomit, feces, or urine providing an origin and permissive environmental factors for microbial contamination," the authors write in a highly comforting introduction to their paper.
To determine just how filthy they are, researchers from the US examined six ball pits located in inpatient physical therapy clinics around Georgia.They randomly selected nine to 15 balls from different depths of each ball pit, then swabbed and analysed them.
The researchers found eight bacteria and one yeast that could cause disease. Additionally, bacterial colonisation was found to be as high as thousands of cells per ball, "which clearly demonstrates an increased potential for transmission of these organisms to patients and the possibility of infection in these exposed individuals," the authors write.
Overall the team identified 31 bacterial species and one species of yeast. The human-associated bacteria found in the ball pits included:
- Enterococcus faecalis, which can cause endocarditis, septicemia, urinary tract infection, and meningitis;
- Staphylococcus hominis, a cause of bloodstream infections and reported as a cause of sepsis in a neonatal intensive care unit;
- Streptococcus oralis, known to cause endocarditis, adult respiratory distress syndrome, and streptococcal shock;
- Acinetobacter lwofii, which has been reported to cause septicemia, pneumonia, meningitis, and urinary tract and skin infections.
"Although it is normal to see human microbes wherever humans are present, further study of the amount of colonisation should be performed and, if warranted, standardised cleaning protocols developed to limit the presence of opportunistic pathogens in this environment," the authors write.
Karen Hoffmann, President of the Association for Professionals in Infection Control and Epidemiology (APIC) who was not involved in the study, adds, "This research shows that ball pits may pose an infection hazard. "Facilities should establish a program for regular cleaning to protect patients and healthcare workers from potential infection risks."
It's not the first time ball pits have been identified as a playground for pathogens. One previous US study found an increased level of normal flora, as well as non-human flora, within ball pits at fast food restaurants.
"Disinfection protocol and proper handwashing are the keys to making ball pit play areas safe for children," the authors wrote at the time.