In Washington and across the United States, all newborns have their hearing checked soon after birth. If a deficit is detected, a string of follow-up testing, treatments, and services is set in motion.
Not so in many other low- or middle-income countries around the world, where child hearing is tested too late, if at all.
A new device developed by a team of researchers at the University of Washington aims to change that. The open-source device uses a smartphone and low-cost earbuds to determine whether a baby has hearing loss.
Test results show it’s an accurate, affordable alternative to the expensive commercial testing systems used in most American hospitals. The new tool performed as well as the conventional device, correctly identifying all patients who had hearing loss. The results were published earlier this fall in the journal Nature Biomedical Engineering.
Making testing accessible
“There is a huge amount of health inequity in the world. I grew up in a country where there was no hearing screening available, in part because the screening device itself is expensive,” said Shyam Gollakota, a study author and UW computer and engineering professor. “The project here is to leverage the ubiquity of mobile devices people across the world already have — smartphones and $2 to $3 earbuds — to make newborn hearing screening something that’s accessible to all without sacrificing quality.”
The research team first tested the smartphone device on 114 patients – including 52 babies younger than 6 months — in three Puget Sound clinics. They also tested the device on pediatric patients with known hearing loss. A second study focused on 130 babies less than 6 months old. Seattle Children’s Dr. Emily Gallagher, a UW associate professor of pediatrics, said all these local families were key to the device’s development and testing process.
“We are so grateful — these families truly made a difference in this project,” Gallagher said. “They volunteered selflessly. We explained this screening test would not replace any evaluation their children may need in audiology, and it was heartwarming to see families happy to participate regardless. Without their help, it would be much more difficult to continue the research in other countries, where we expect the device to have the biggest impact.”
How it works
Earbuds for the screening are connected to a microphone in a probe that is placed in an infant’s ear to detect the mechanics within the ear. When an external sound is played, hair cells in the inner ear move and vibrate. The result is a very quiet sound. The microphone records such sounds if detected and sends them to a smartphone for processing. The inexpensive earbuds replace the expensive speaker used in commercial testing.
The project moves to Kenya
Researchers are now using their prototype device to screen newborn hearing in Kenya in collaboration with the University of Washington’s global health department, the University of Nairobi, and the Kenya Ministry of Health. The project there, ready to roll once funding is secured, will provide vital information on how to scale-up use of the new device, especially in countries where infant hearing screening is lowest.
“Most of Africa and much of South Asia does not screen infants and newborns for hearing,” said Gallagher. “The risk factors for hearing loss in these countries is much higher than in parts of the world where we screen most newborns, so the potential impact of this low-cost hearing screening device is enormous.”
Beta testing the device in Kenya was a logical choice, Gallagher said. UW researchers have an established collaborative relationship with Kenyans researching, among other things, the impacts of HIV exposure in utero on hearing and development in children. HIV-exposed infants and children have an increased risk of hearing loss, so partnering with those ongoing studies to try to improve testing options for patients made sense.
A World Hearing Day committment
At the same time, the country also has universal health care, and 75% of babies are born in hospitals. Researchers say that will make introducing the concept of universal screening to the country easier.
Most importantly, Gallagher said, Kenya has shown a commitment to building a system to support kids with hearing loss.
“If a country is going to screen infants for hearing, they must also have a plan for those who do not pass a screening test, understand cultural perspectives about hearing loss, and support community awareness and caregiver engagement,” said Gallagher. “Without these things in place, we would not recommend screening.”
On World Hearing Day this year, the Kenya health ministry signed a national strategy for ear and hearing care for Kenya. It includes support for hearing assessment tools, hearing aids, and educational support for Kenyans with hearing loss.
A model for countries around the globe
“Our work in Kenya will hopefully be a model for other countries interested in developing Ear and Hearing Care national programs,” she said. “Personally, I am dedicated to continuing this work to make sure all children, regardless of where they are born, have access to hearing screening and appropriate support when needed.”
To follow the project or donate to this ongoing research, go to the project website: TUNE: Toward Universal Newborn and Early Childhood Hearing Screening in Kenya
Sarah McQuate is a writer for UW News contributed to this article.