ABSTRACT Hearing loss is among the leading causes of disability worldwide, with the highest burden in resource limited settings (RLS). Children are disproportionately affected, given the detriment to a child’s neurocognitive and social development, yet the impacts can be mitigated if detected and treated early. Nearly 60% of hearing loss in children is due to preventable factors, and identification is the first step in addressing hearing loss. High income countries have implemented universal newborn hearing screening (UNHS) programs with a goal of diagnosing hearing loss and starting early intervention in the first few months of life. Few comparable programs exist in low and middle income countries, given such barriers as limited access to trained personnel and high cost of hearing screening equipment. We propose to optimize a low-cost smartphone otoacoustic emissions (OAE) device for hearing screening and study the implementation in an RLS. The smartphone OAE is comparable to conventional hearing screening equipment in US trials and now must be evaluated where it can have the greatest impact. The aims of the R21 are to optimize the OAE device in various clinical settings and patient ages in Kenya. We will evaluate potential impact of noisy clinical environments, assess consistency of screening, and compare usability in frontline and lay health facility workers, with a deliverable of a low-cost, user-friendly OAE that is a feasible tool in a low- resource clinical setting. Work will begin to integrate hearing screening results from the smartphone OAE directly with electronic medical records systems in Kenya. The R33 will further establish implementation outcomes and validity of the smartphone OAE device in a UNHS program, and will provide an in-depth evaluation of the implementation strategy and task-shifting in the Kenyan context. In parallel, the R33 will deploy the smartphone OAE in a longitudinal study of suspected (HIV exposure) and known (otitis media with effusion) risk factors for hearing loss. The longitudinal study will leverage an additional innovative lay-person friendly smartphone tool that can be used to monitor for middle ear fluid, an important companion for hearing screening in children that typically relies on expensive, skill intensive equipment. The research team includes medical providers, public health researchers, computer scientists and the Technical Working Group for Ear and Hearing Care in Kenya’s Ministry of Health, a collaboration that will support program sustainability when the project is complete. The project establishes a foundation for smartphone OAE in UNHS programs, high-risk infant surveillance, ototoxicity monitoring, and future research to understand and improve ear and hearing care in RLS. The outcomes of this work align with the goals of the WHO World Report on Hearing, which strives for all people, including those with hearing loss, to have access to high-quality services without experiencing financial hardship by 2030.

NARRATIVE Hearing loss in infants is a “developmental emergency”, and early hearing detection, intervention, and hearing loss prevention are central to national strategies for ear and hearing care. Building on collaborations with the Technical Working Group for Ear and Hearing Care in Kenya’s Ministry of Health, we will optimize and test implementation outcomes for smartphone-based universal hearing screening for newborns and infants. Among infants with HIV exposure, a population of interest for hearing surveillance, we will deploy serial hearing screening coupled with simple smartphone-based detection of middle ear fluid and determine rates of otitis media with effusion, a modifiable risk factor for early hearing loss.