Newborn hearing screening in a developing country: results of a pilot study in Abidjan, Côte d'ivoire

The Otoacoustic Emissions in the Universal Neonatal Hearing Screening: A Scoping Review Update on the African Data (2004 to 2024)

Background: The reported data on African universal neonatal hearing screening (UNHS) practices tend to be quite scarce, despite the developments in hearing screening the last two decades. The objective of this systematic review was (a) to identify the most recent (in a 20-year span) literature information about NHS/UNHS programs in Africa and (b) to provide data on the procedures used to assess the population, the intervention policies, and on the estimated prevalence of congenital hearing loss with an emphasis on bilateral hearing loss cases. Methods: Queries were conducted via the PubMed, Scopus, and Google Scholar databases for the time window of 2004-2024. The mesh terms used were "OAE", "universal neonatal hearing screening", "congenital hearing loss", "well babies", and "Africa". Only research articles and review papers were considered as good candidates. The standard English language filter was not used, to identify information from non-English-speaking scientific communities and groups. Results: Data from 15 papers were considered, reflecting the neonatal hearing practices of nine African states. No country-wide NHS programs were reported. The various screening realities are implemented within big urban centers, leaving the residents of rural areas unassisted. For the latter, proposals based on tele-medicine protocols have been suggested. The data on HL prevalence are also incomplete, but the available data refer to rates from 3 to 360 subjects per 1000. These data cannot be taken at face value but within the small sample size context in which they were acquired. Regarding the causes of HL, very few data have been reported; consanguinity is the most attributed factor, at least in the Sub-Saharan African states. For the majority of the programs, no data were reported on hearing loss prevalence/incidence or on any strategies to restore hearing. Conclusions: The information on the African neonatal hearing screening are quite scarce, and it is an urgent need to convince audiologists from the African localized programs to publish their hearing screening data.

Early Hearing Detection and Intervention programmes for neonates, infants and children in non-Asian low-income and middle-income countries: a systematic review

INTRODUCTION

Early Hearing Detection and Intervention (EHDI) programmes were established to reduce the impact of hearing loss on children. High-income countries (HICs) have resources and knowledge to execute these programmes. However, financial and other resource constraints limit the availability of these programmes to low-income and middle-income countries (LMICs). Yet, LMICs have explored strategies to implement EHDI programmes in their context; the outcomes are still largely unknown.The aim of this study is to identify the various models of the EHDI program implemented in non-Asian LMICs.

AIM

METHOD: Studies published between 2010 and 2023 reporting EHDI programmes in non-Asian LMICs for children were considered. The primary databases searched were PubMed, Scopus, Web of Science, EBSCOHost, EBSCO-CINAHL and ProQuest dissertations. The search results are summarised using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses chart. Quality appraisal and risk-of-bias assessment were assessed. Using the retrieved data, a narrative synthesis of the identified methods and forest plots for the prevalence estimate was created.

RESULTS

Fifty-six studies from 16 LMICs were included. They were grouped into 29 hearing screening programmes for neonates and infants and 26 programmes for older children. Predominantly hospital-based screening was employed for neonates and infants and school-based screening for older children. Two-stage otoacoustic emissions screening was employed for neonates and infants, while single-stage pure tone audiometry with otoscopy screening was used for older children. Predominantly, audiologists performed screening and diagnostics for neonates/infants while community health workers performed screening for the older children. Screening aspects were reported predominantly and not diagnostic evaluation/intervention outcomes. Overall, the economics of EHDI was reported only anecdotally in a few studies.

CONCLUSION

The screening strategies were not uniform among non-Asian LMICs. The protocols used were similar to HICs, yet few developed protocols adapting the Joint Committee of Infant Hearing. However, long-term outcomes such as rate of identification, suitable intervention and their outcomes are not known. EHDI programmes with successful outcomes of early intervention must be studied and reported with economic evaluations.

First report of an Ivorian family with nonsyndromic hearing loss caused by GJB2 compound heterozygous variants

The primary etiology of congenital hearing loss is attributed to genetic factors, with GJB2 identified as a pivotal gene across diverse ethnic groups. Additionally, nonsyndromic hearing loss is predominantly inherited in an autosomal recessive manner. We used Sanger sequencing to analyze GJB2 in 17 deaf children from 13 unrelated Ivory Coast families. One family had two children born with severe congenital deafness and exhibited pathogenic compound heterozygous variants. These variants included a nonsense substitution (c.132G > A or p.Trp44Ter) and a newly discovered duplication of 7 base pairs (c.205_211dupTTCCCCA or p.Ser72ProfsTer32). Segregation testing confirmed these variants, marking the first identification of GJB2 in an Ivorian family with congenital hearing loss.

Cost-effectiveness of screening for developmental dysplasia of the hip in Karachi, Pakistan using a universally applicable cost-effectiveness model

Introduction

Developmental dysplasia of the hip (DDH) is a congenital anomaly of the hip socket that can lead to lifelong disability and pain when left untreated. DDH is a good candidate for screening because of its high frequency in population, availability of treatment and the possibility of secondary prevention. Pakistan currently does not have any systematic or universal neonatal screening programme for DDH.

Methods

The cost-effectiveness model in this study uses one decision tree for each screening scenario: (1) the status quo, (2) universal screening by clinical examination, (3) universal screening by clinical examination with targeted ultrasound (US) screening, (4) and universal screening by US. Loss of disability-adjusted life-years (DALYs) is used as outcome variable.

Results

When left untreated DDH creates a loss of 3.4 DALYs per person. Clinical examination and targeted US averts most DALYs per dollar spent. Generalised US averts more DALYs overall but requires a greater financial investment per DALY averted.

Conclusions

Universal US screening reaches more children and can be considered the more equitable approach but requires 10 times the financial investment clinical examination and targeted US requires. The decision which option is most appropriate for Karachi, Pakistan depends on resource availability, geography, infrastructure, treatment capacity, health system values and societal factors in Pakistan.

Barriers to access to ear and hearing care services in low- and middle- income countries: A scoping review

People living in low- and middle- income countries (LMICs) meet significant challenges in accessing ear and hearing care (EHC) services. We conducted a scoping review to identify and summarise such barriers, to recognise gaps in the literature, and to identify potential solutions. Reviewers independently screened titles, abstracts and full-text articles and charted data. We undertook thematic analysis of supply and demand side dimensions of access, and summarised findings mapped against the Levesque framework. Of 3048 articles screened, 62 met inclusion criteria for review. Across the five access dimensions, supply-side constraints were more frequently described, the most common being a shortage of EHC workforce or appropriate facilities, despite high demand. We identified a thin geographical spread of literature on barriers to accessing EHC services in LMICs, reflecting low availability of such services. LMICs face a diverse range of demand and supply side challenges including workforce, equipment and resource shortages, and challenges for the majority of the population to pay for such services. There is a need for many LMICs to develop health policy and programmes in EHC, including integration into primary care, scaling up the EHC workforce through increased training and education, and improving EHC literacy through public health measures.

Protocol and programme factors associated with referral and loss to follow-up from newborn hearing screening: a systematic review

BACKGROUND

An effective newborn hearing screening programme has low referral rate and low loss to follow-up (LTFU) rate after referral from initial screening. This systematic review identified studies evaluating the effect of protocol and programme factors on these two outcomes, including the screening method used and the infant group.

METHODS

Five databases were searched (latest: April 2021). Included studies reported original data from newborn hearing screening and described the target outcomes against a protocol or programme level factor. Studies were excluded if results were only available for one risk condition, for each ear, or for < 100 infants, or if methodological bias was observed. Included studies were evaluated for quality across three domains: sample, screening and outcome, using modified criteria from the Ottawa-Newcastle and QUADAS-2 scales. Findings from the included studies were synthesised in tables, figures and text.

RESULTS

Fifty-eight studies reported on referral rate, 8 on LTFU rate, and 35 on both. Only 15 studies defined LTFU. Substantial diversity in referral and LTFU rate was observed across studies. Twelve of fourteen studies that evaluated screening method showed lower referral rates with aABR compared to TEOAE for well babies (WB). Rescreening before hospital discharge and screening after 3 days of age reduced referral rates. Studies investigating LTFU reported lower rates for programmes that had audiologist involvement, did not require fees for step 2, were embedded in a larger regional or national programme, and scheduled follow-up in a location accessible to the families. In programmes with low overall LTFU, higher LTFU was observed for infants from the NICU compared to WB.

CONCLUSION

Although poor reporting and exclusion of non-English articles may limit the generalisability from this review, key influential factors for referral and LTFU rates were identified. Including aABR in WB screening can effectively reduce referral rates, but it is not the only solution. The reported referral and LTFU rates vary largely across studies, implying the contribution of several parameters identified in this review and the context in which the programme is performed. Extra attention should be paid to infants with higher risk for hearing impairment to ensure their return to follow-up.

Feasibility of establishing an infant hearing screening program and measuring hearing loss among infants at a regional referral hospital in south western Uganda

Introduction

Despite the high burden of hearing loss (HL) globaly, most countries in resource limited settings lack infant hearing screening programs(IHS) for early HL detection. We examined the feasibility of establishing an IHS program in this setting, and in this pilot program measured the prevalence of infant hearing loss (IHL) and described the characteristics of the infants with HL.

Methods

We assessed feasibility of establishing an IHS program at a regional referral hospital in south-western Uganda. We recruited infants aged 1 day to 3 months and performed a three-staged screening. At stage 1, we used Transient Evoked Oto-acoustic Emissions (TEOAEs), at stage 2 we repeated TEOAEs for infants who failed TEOAEs at stage 1 and at stage 3, we conducted Automated brainstem responses(ABRs) for those who failed stage 2. IHL was present if they failed an ABR at 35dBHL.

Results

We screened 401 infants, mean age was 7.2 days (SD = 7.1). 74.6% (299 of 401) passed stage 1, the rest (25.4% or 102 of 401) were referred for stage 2. Of those referred (n = 102), only 34.3% (35 of 102) returned for stage 2 screening. About 14.3% (5/35) failed the repeat TEOAEs in at least one ear. At stage 3, 80% (4 of 5) failed the ABR screening in at least one ear, while 25% (n = 1) failed the test bilaterally. Among the 334 infants that completed the staged screening, the prevalence of IHL was 4/334 or 12 per 1000. Risk factors to IHL were Newborn Special Care Unit (NSCU) admission, gentamycin or oxygen therapy and prematurity.

Conclusions

IHS program establishment in a resource limited setting is feasible. Preliminary data indicate a high prevalence of IHL. Targeted screening of infants at high risk may be a more realistic and sustainable initial step towards establishing IHS program s in a developing country like Uganda.

Neonatal hearing screening, with otoacoustic emission, among normal babies in a northeastern Nigerian hospital

Background:

Hearing is necessary for speech and language development, children with bilateral hearing loss often have impaired speech and language abilities thus limiting educational attainment. Early detection and intervention will help minimize such effects. Therefore, neonatal hearing screening program has been advocated in developing countries.

Objective:

TThe objective of this study is to determine the prevalence of hearing loss and risk factors among full-term inborn neonates delivered in a University Teaching Hospital with transient evoked otoacoustic emission (TEOAE).

Materials and Methods:

All full-term neonates delivered in a University Teaching Hospital were included in this prospective cross-sectional study. The hospital’s ethical committee gave approval. The researcher obtained informed consent from the parents and administered a questionnaire for demographic, prenatal, and postnatal data. A comprehensive head and neck examination preceded the preliminary otoscopy. With the help of a hand-held otodynamic otoport, Neonatal Hearing Screening Program otoacoustic emission (OAE), each ear’s hearing was assessed. Statistical Product and Service Solutions (SPSS) version 22.0 was used to analyse the data.

Results:

150 full-term neonates were screened, of which 72 (48%) were males and 78 (52%) were females. Neonates that failed the TEOAE in both ears were 12 (8%). 18 (12%) neonates had a refer in right ear only, while 24 (16%) had a refer in the left ear only. The only significant risk factor with a referral outcome of TEOAE was family history of childhood hearing loss (23.1%).

Conclusion:

This study found a high prevalence (8%) of failed TEOAE of full-term neonates delivered in our hospital with a significant risk factor of family history of childhood hearing loss.

Evaluation of transient-evoked otoacoustic emissions in a healthy 1 to 10 year pediatric cohort in Sub-Saharan Africa

OBJECTIVE

Transient-evoked otoacoustic emissions (TEOAEs) monitor cochlear function. High pass rates have been reported for industrialized countries. Pass rates in low and middle income countries such as Sub-Saharan Africa are rare, essentially lower and available for children up to 4 years of age and frequently based on hospital recruitments. This study aims at providing additional TEOAE pass rates of a healthy Sub-Saharan cohort aged 1-10 years with data from Gabon, Ghana and Kenya. Potentially confounding factors (recruitment site, age) are taken into consideration.

METHODS

Healthy children were recruited in hospitals, schools and kindergartens. Inclusion criteria were age 1-10 years and normal otoscopic findings. Exclusion criteria were any sickness or physical ailment potentially impairing the hearing capacity. Five measurements per ear were performed with Capella Cochlear Emission Analyzer (MADSEN, Germany). An overall wave reproducibility of above 60% served as pass-criterion. Pass rates were compared between recruitment sites and age groups (1-5 and 6-10 years).

RESULTS

Overall pass rate was 87.5% (n = 264; 231 passes vs. 33 fails). Of these 84.0% of hospital recruited children passed (n = 156; 131 passes vs. 25 fails), compared to 92.6% of community recruitments (n = 108; 100 passes vs. 8 fails), which was significantly different p = 0.039). If analyzed by age groups, this difference was only observed in children younger than 6 years (p = 0.007).

CONCLUSION

Hospitals as recruitment sites for healthy controls seem to affect TEOAE pass rates. We advise for a cautious approach when recruiting healthy TEOAE control collectives under the age of 6 in a hospital setting. In children older than 6 years conventional pure-tone audiometry remains the standard method for hearing screening.

Neonatal hearing screening in a rural/sub-urban community in Nigeria, sub-Saharan Africa-a preliminary report

INTRODUCTION

The implementation of Neonatal Hearing Screening (NHS) program is still at the preliminary stage particularly in developing countries despite the burden of permanent congenital and early-onset hearing impairment. There has been an earlier report of NHS in a city in Nigeria, however, this is a report of a preliminary NHS carried in a rural/sub-urban area in Nigeria.

METHOD

This prospective study, which took place between October 2009 and April 2010, involved all newborns delivered at the University College Hospital, Ibadan and the Bilal Missionary Maternity, Agodi, Ibadan, a small maternity service located in Agodi community serving predominantly low socioeconomic class people. All the neonates delivered during the study period were included in the screening. The screening was performed within 72 h of delivery using automated auditory brainstem response (AABR) and repeated after 6 weeks among those with referral result. Subsequently the neonates were referred to diagnostic audiology.

RESULT

Among the 453 newborns (231 males and 222 female), AABR screening showed referral, in 43.7% of neonates. At first screening, 224 (49.4%) were referred while 229 (50.6%) passed, however, during the post-natal period 40/229 (17.5%) reported for second screening, out of these 26 showed pass to the screening. This gave a total pass of 255/453 (56.3%). The presence of maternal pre-ecclampsia (P = 0.05) was found to be a significant morbidity factor associated with referral in the screening, while parental socioepidemiological variables; and the neonates' birthweight, gestational age and APGAR score were not.

CONCLUSION

The proportion of referral on hearing screening encountered was far higher than previously reported, however, continuation of infant screening in future should be comprehensive with viral and genetic analysis in order to address the issue of aetiologic diagnosis; in addition, the implementation should factor the high drop out from the first stage screening in order to substantiate the findings in our region.

Newborn hearing screening and early diagnostic in the NICU

The aim was to describe the outcome of neonatal hearing screening (NHS) and audiological diagnosis in neonates in the NICU. The sample was divided into Group I: neonates who underwent NHS in one step and Group II: neonates who underwent a test and retest NHS. NHS procedure was automated auditory brainstem response. NHS was performed in 82.1% of surviving neonates. For GI, referral rate was 18.6% and false-positive was 62.2% (normal hearing in the diagnostic stage). In GII, with retest, referral rate dropped to 4.1% and false-positive to 12.5%. Sensorineural hearing loss was found in 13.2% of infants and conductive in 26.4% of cases. There was one case of auditory neuropathy spectrum (1.9%). Dropout rate in whole process was 21.7% for GI and 24.03% for GII. We concluded that it was not possible to perform universal NHS in the studied sample or, in many cases, to apply it within the first month of life. Retest reduced failure and false-positive rate and did not increase evasion, indicating that it is a recommendable step in NHS programs in the NICU. The incidence of hearing loss was 2.9%, considering sensorineural hearing loss (0.91%), conductive (1.83%) and auditory neuropathy spectrum (0.19%).

Gestational vitamin A deficiency: a novel cause of sensorineural hearing loss in the developing world?

Hearing loss is a substantial public health problem with profound social and economic consequences in the developing world. The World Health Organization (WHO) estimates that there are 360 million people living with disabling hearing loss globally, and 80% of these individuals are from low- and middle-income countries. The epidemiology of hearing impairment remains poorly defined in most impoverished societies. Middle ear infections in childhood are a key determinant; however, congenital anomalies may also comprise an important etiology and may arise from gestational malnutrition. While evidence exists that preventable vitamin A deficiency exacerbates the severity of ear infections and, consequently, hearing loss, antenatal vitamin A deficiency during sensitive periods of fetal development may represent an etiologically distinct and virtually unexplored causal pathway. Evidence from multiple animal systems clearly shows that fetal inner ear development requires adequate vitamin A nutriture to proceed normally. Inner ear malformations occur in experimentally imposed maternal vitamin A deficiency in multiple species in a dose-response manner. These anomalies are likely due to the loss of retinoic acid-dependent regulation of both hindbrain development and otic morphogenic processes. Based on in vivo evidence in experimental animals, we hypothesize that preventable gestational vitamin A deficiency, especially during early stages of fetal development, may predispose offspring to inner ear malformations and sensorineural hearing loss. As vitamin A deficiency affects an estimated 20 million pregnant women globally, we hypothesize that, in undernourished settings, routine provision of supplemental vitamin A at the recommended allowance throughout pregnancy may promote normal inner ear development and reduce risk of an as yet unknown fraction of sensorineural hearing loss. If our hypothesis proves correct, gestational vitamin A deficiency would represent a potentially preventable etiology of sensorineural hearing loss of substantial public health significance.

A large-scale newborn hearing screening in rural areas in China

OBJECTIVES

Newborn hearing screening has been successfully implemented in cities of China, but not in rural areas. This study aimed to provide guidance on implementing hearing screening in the rural areas of China.

METHODS

Subjects were 11,568 babies who were born in 5 counties of Hubei Province of China. Hearing screening followed a two-stage strategy with transient evoked otoacoustic emissions (TEOAEs). Infants referred after the second-stage screening were tested by diagnostic auditory brainstem response (ABR).

RESULTS

The subjects screened included 10,665 (92.2%) normal newborns and 903 (7.8%) newborns with high-risk of hearing loss. While 8190 (70.8%) newborns passed the initial screening, 135 newborns failed in the re-screening, and 90 (66.7%) of these 135 newborns received diagnostic assessment. Finally, 58 infants were diagnosed as hearing loss, and the prevalence of congenital hearing loss among newborns in rural areas was 0.5% (58/11,568).

CONCLUSIONS

This large-scale newborn hearing screening in rural areas of Hubei Province of China demonstrated that the screening rate and referral rate for high-risk infants are low. Urgent measures should be taken by the government to promote newborn hearing screening in the rural areas.

Neonatal hearing screening and intervention in resource-limited settings: an overview

From a developmental perspective, optimal speech and language outcome is indisputably the primary motivation for neonatal hearing screening of infants with congenital or early-onset hearing loss (PCHL). This paper additionally outlines more broadly the potential value of early hearing detection and intervention in resource-poor countries against the backdrop of limitations of primary prevention of PCHL based on a review of literature from low-income and middle-income countries with per capita incomes of approximately US$6000 or less. It establishes the scientific and developmental foundation for priority consideration for neonatal hearing screening and intervention in any global initiatives for effective early childhood development programmes in resource-limited countries. It also highlights approaches to addressing the various challenges to implementing effective early hearing detection and intervention programmes, and concludes with a discussion on the pivotal role of paediatricians in facilitating timely referral for requisite tests and (re)habilitative services especially for infants with established risk factors.

Prevalence of auditory changes in newborns in a teaching hospital

Introduction: The precocious diagnosis and the intervention in the deafness are of basic importance in the infantile development. The loss auditory and more prevalent than other joined riots to the birth.

Objective: Esteem the prevalence of auditory alterations in just-born in a hospital school.

Method: Prospective transversal study that evaluated 226 just-been born, been born in a public hospital, between May of 2008 the May of 2009.

Results: Of the 226 screened, 46 (20.4%) had presented absence of emissions, having been directed for the second emission. Of the 26 (56.5%) children who had appeared in the retest, 8 (30.8%) had remained with absence and had been directed to the Otolaryngologist. Five (55.5%) had appeared and had been examined by the doctor. Of these, 3 (75.0%) had presented normal otoscopy, being directed for evaluation of the Evoked Potential Auditory of Brainstem (PEATE). Of the total of studied children, 198 (87.6%) had had presence of emissions in one of the tests and, 2 (0.9%) with deafness diagnosis.

Conclusion: The prevalence of auditory alterations in the studied population was of 0,9%. The study it offers given excellent epidemiologists and it presents the first report on the subject, supplying resulted preliminary future implantation and development of a program of neonatal auditory selection.