Promising Solution for Pediatric Ear Infections and Related Antibiotic Resistance Developed by Cornell Researchers

Researchers at Cornell University have developed a breakthrough single-use nanoscale system that demonstrates promising results in reducing or eradicating Streptococcus pneumoniae, a bacteria responsible for acute ear infections. The innovative approach—inspired by the active ingredient in household bleach as well as a chemical process found in giant kelp—offers a possible future solution to the challenges in treating childhood ear infections without contributing to antibiotic resistance.

The researchers presented their findings at the American Chemical Society (ACS) Fall 2023 meeting and provided a summary via a press release in Eurekalert.

Childhood ear infections are a pervasive issue affecting over 95% of children in the United States and are the leading cause of pediatric doctor visits. While antibiotics have been the go-to solution, incomplete courses of antibiotics can lead to antibiotic resistance—a growing global health concern. Current treatment mandates a rigorous regimen of multidose antibiotics over 5–10 days, and systemic antibiotic exposure or premature termination of treatment to young patients is believed to worsen the incidence of antibiotic resistance.

To combat this problem, the Cornell University team turned to hypochloric acid, a component of bleach that bacteria have not yet developed significant resistance to.

“We initially conceived of this idea by looking at the household cleaner bleach. Even though it has been used since the 19th century, bacteria do not appear to have developed any widespread resistance to this cleaner,” said Rong Yang, PhD, the project’s principal investigator, in the press release.

Dr. Yang emphasizes that using bleach to treat infections is dangerous and ineffective due to its high concentration and caustic nature. However, when used in controlled low concentrations, the active ingredient in bleach can interact with living tissue without harm. This insight led the team to explore the possibility of using a bleach-related compound to target bacteria causing ear infections.

The researchers aimed to create an on-demand hypobromous acid (HOBr) production system within the middle ear where ear infections occur. Taking inspiration from an enzyme in giant kelp, which converts hydrogen peroxide (H²O²) to hypobromous acid (HOBr), the team designed vanadium pentoxide (V²O⁵) nanowires. These nanowires, resembling rods, release hypobromous acid in the presence of H²O²-producing bacteria while minimizing diffusion into body fluids.

Testing this approach on chinchillas, which experience similar ear infections to human children, the researchers successfully reduced Streptococcus pneumoniae bacteria, a common ear infection culprit. The chinchillas' inflamed eardrums returned to normal after treatment with the nanowires. Notably, the treatment did not impair the animals' hearing, suggesting its potential safety for human application.

Video from the American Chemical Society describing how Cornell researchers are treating earaches with nanoparticles that generate antiseptic on demand. Closed captions are available on this video. If you are using a mobile phone, please enable captions clicking on the gear icon.

Because these substances are reactive and break down quickly, Yang and her colleagues sought to generate one of them on an as-needed basis behind the eardrum in the middle ear, where ear infections occur. They developed a practical method to deliver the treatment topically as a gel into the ear canal. By incorporating peptides known for facilitating particle transport through the eardrum, the nanowires within the gel effectively passed through the intact tissue. This less invasive approach may open the door for a more convenient and user-friendly treatment option, and they are also exploring other approaches for passing the nanowires through the eardrum.

In addition to their success with Streptococcus pneumoniae, the researchers are also exploring the system's effectiveness against other bacteria that cause ear infections. While the duration of the nanowires' effectiveness remains to be studied, the researchers believe they might modify the nanowires’ properties to stay in place for extended periods, potentially preventing recurrent infections.

“If the bacteria return, the system could restart, so children wouldn't need antibiotics repeatedly and breed more resistance along the way,” Yang says.

Yang envisions a future where the nanoscale system could be reactivated if bacteria return, eliminating the need for repeated antibiotic use and reducing the risk of antibiotic resistance development. By harnessing the power of nanotechnology and innovative delivery methods, this groundbreaking research offers a promising solution to treating childhood ear infections without contributing to antibiotic resistance.

As the ACS Fall 2023 meeting showcases this research, it holds the potential to revolutionize the way we approach and treat common childhood infections, paving the way for a healthier and more antibiotic-resistant-free future.

The researchers acknowledge support and funding from the National Institute on Deafness and Other Communication Disorders (NIDCD).