How Clean Are Ball Pits Used for Pediatric Physical Therapy?

Ball pits are something that can be associated with a mix of joy and disgust. Typically, you can find ball pits in commercial family restaurants, children’s museums, or play parks, and although they can be a place of childhood fun and entertainment, it has been well-established that these can also be reservoirs for feces, vomit, and a plethora of germs.

Sure, it’s debatable about just what kind of microbial burden exists in ball pits and how dangerous they might be for those playing in them, but I think we can all safely say that there is a certain amount of gut-wrenching (pun intended) “ick” that comes with seeing them as adults.

These havens for childhood fun are also used for pediatric physical therapy and have a surprisingly effective role in both inpatient and outpatient efforts, as they provide stimulation to aid in therapy for children with sensory and/or motor impairments. Despite this, a new study has raised questions about their role in the spread of pathogenic microorganisms.

Beyond the obvious potential for ball pits to be contaminated, here’s the reason why this study is so important: There is very elusive and murky federal guidance on the cleaning of the ball pits. As the investigators of a study published in the American Journal of Infection Control note, clinics that utilize these ball pits have reported going days or weeks between cleanings. Larger times between cleaning, combined with the presence of patients with skin lesions or abrasions, creates a perfect environment for microbial transmission.

In an effort to assess the true microbial burden of these therapeutic pits the investigators sampled 6 ball pits in inpatient and outpatient physical therapy clinics in the state of Georgia. Nine to 15 balls were collected from various depths of each pit. Samples were collected and swabbed, inoculated via soy agar plates, and grown for 24 hours.

After reviewing the colony-forming units (CFUs), the study team found some pretty interesting microbial growths between the various clinics and ball pits. Of the 6 clinics, some had larger quantities of balls in their pits. In Clinic B, 93% of the balls had >3.0x10⁴CFUs, while Clinic A had the least (36% of the balls had <3.0x10¹CFUs). This sort of variation is likely due to differences in cleaning protocols, both in terms of EPA-registered disinfectants and the frequency of cleaning.

The investigators did find bacterial colonization as high as thousands of cells per ball, which would suggest a high risk of transmission. Thirty-one bacterial species were identified in the sample cultures, as well as 1 yeast. Of these samples, there was quite a variable of microbial growth, including organisms like Streptococcus oralis and Enterococcus faeclis, and gram-negative bacteria like Pseudomonase fragi and Acinetobacter lwoffii.

These are just a few of the organisms the investigators found when sampling the ball pits of the 6 pediatric physical therapy clinics. Although it’s not surprising to find microbial growth on such high-touch surfaces, especially in a pediatric physical therapy environment, this study calls into question the concerning lack of clear guidance on cleaning protocols for ball pits used in clinical settings.

Consider a daycare setting where a ball pit might exist and a disease that tends to spread easily, like hand, foot, and mouth disease. In these situations, disinfecting everything is critical, and should involve a bleach-water mixture. Unfortunately, there are few guidelines and protocols for both clinical and commercial settings to ensure disinfection or cleaning of equipment like ball pits.

From the infection control standpoint, a mixture of patient hand hygiene and several iterations of disinfecting with Clorox bleach each week would be preferable. It is unlikely that staff would be able to clean the ball pit and each ball daily, but with hand hygiene and disinfection of the entire equipment 2-3 times a week, the odds of transmission are significantly reduced.

This study emphasizes the need to address the role of such physical therapy equipment in microbial contamination and burden, but also how we address cleaning of such equipment. It behooves us to establish more stringent guidelines in both clinical and commercial settings.