Universal Neonatal Hearing Screening (UNHS) programs have already been implemented in some parts of the world – notably, in the United States and Poland – while pilot programs are running in other countries all around the world, including the United Kingdom, Canada, Cyprus, Australia, Brazil, Austria, Italy, to name but a few.
An invisible handicap
It has long been recognized that hearing loss present at birth typically goes undetected until delays in language development eventually lead to the clinical investigation of a child's ability to hear.
In the past, it was common for the average age of identification to be 2-3 years, with milder losses frequently not being recognized until the child reaches school age. And since language acquisition actually begins at birth and progresses rapidly during the first three years of life, undetected hearing impairments in infants can negatively impact speech and language acquisition, academic achievement, and social and emotional development.
Ongoing research (and notably a study by Christine Yoshinaga-Itano, Ph.D.,) has clearly demonstrated that, if detected early, the negative impacts of hearing impairment can be diminished and even eliminated through early intervention.
Slow progress
Since the 1950s, expert groups in the United States and Europe have emphasized the need to detect hearing loss early, but little progress was made until the late 1980s when otoacoustic emissions (OAE) technology appeared (technology which permits non-invasive, objective hearing screening). Likewise, in 1989, U.S. Surgeon General C. Everett Koop declared that, by the year 2000, all infants with significant hearing loss would be identified before 12 months of age.
By the 1990s, federal initiatives in the U.S., combined with improved technology and concerted action from hospitals and state agencies, led to dramatic advances in procedures for early identification. By 1993, about 20 hospitals in the U.S. and around the world were operating UNHS programs.
Gathering momentum
Based on evidence that screening was effective, practical, and cost efficient, the U.S. National Institutes of Health (NIH) recommended in March, 1993, that all newborns should be screened for hearing impairment prior to hospital discharge. This led to UNHS programs being started up in state after state across the whole of the U.S.
The Marion Downs National Center at The University of Colorado was founded by a federal grant for the coordination of statewide systems for screening, diagnosis, and intervention for newborns and infants with hearing loss. From 1996 to 2000, the center coordinated the implementation of universal newborn hearing screening programs in 17 states under a grant from the U.S. Public Health Service.
And at a pioneering meeting in 1998, the European Consensus Development Conference on Newborn Hearing Screening (NHS) was held in Milan, Italy, at the initiative of Dr. Ferdinando Grandori. With enthusiastic participation from all over the world, the conference was devoted to showing the practical feasibility of UNHS. The conference has since been held every two years.
Early Hearing Detection and Intervention (EHDI)
Through the 1990s, the focus had been on UNHS – how could such a program be established? At what cost? Who would do the actual screening, and with what equipment? How could all the data be managed, and what constituted acceptable results? By the end of the decade, these questions had been answered, and numerous programs were in place, with varying degrees of success.
The focus then switched from hearing screening to what to do with those infants identified in such programs – after all, it was obvious that identifying hearing impairment in a baby and then not doing anything about it was an unnecessary cause of anxiety and trauma to parents.
Today, there is a broad consensus that infants referred from UNHS programs should receive a follow-up diagnostic audiologic evaluation before 3 months of age. This evaluation serves to verify the existence of a hearing impairment, and when present, the aetiology and severity. Intervention can be carried out by fitting one or more hearing aids, with the option of cochlear implantation further down the road.