Abstract:
Introduction: Hearing loss is one among the major abnormalities present at birth. If
undetected will impair speech, language and cognitive development. The critical period
for language and speech development is generally regarded as the first three years of
life. Children who are identified with hearing at early stage of life and receive early and
appropriate interventions have significantly higher developmental functions than those
with late identification and intervention.
Objective: The study aimed at determining the prevalence of hearing loss among
neonates born in Zanzibar, which is part of United Republic of Tanzania.
Study design: Hospital-based, prospective cross sectional study
Method: This was prospective cross sectional study and conducted in three hospitals
and one health Centre where neonatal hearing screening was done in Zanzibar. All
babies born from May to October 2016 and whose parents/caretakers consented,
enrolled in the study. Data collected using a three staged protocol neonatal hearing
screening with OAE and AABR, and other information was collected clinically using
specialized forms and check list. A total of 600 neonates were recruited in this study and
the data analyzed using the SPSS program.
Results: This study included 600 neonates. Among these, 323 (53.8%) were females and 277
(46.2%) were males. Neonates who underwent 1st OAE, 36.2% failed the test and went
for second test. For those who underwent 2nd OAE, 13.8% failed the test and went for
AABR. 41.4% of those who went for AABR failed and went for Diagnostic ABR and
among these only 3 (25%) failed. Three neonates were diagnosed with hearing loss and
they were all males, with bilateral SNHL, making a prevalence of 0.5%. Among those
with hearing loss 33.3% had severe SNHL and 66.7% profound SNHL. The most
frequent risk factor was ototoxic medication use (11.8%) followed by low apgar score
(11%) and family history of childhood hearing loss (7%) and hyperbilirubinemia (2.5%).
Hyperbilirubinemia was the only risk factor significantly associated with hearing loss
(p=0.001)
Conclusion: The prevalence of hearing loss in neonates was 0.5%, more common in males, bilateral,
sensorineural type and associated with risk factors.
