Deafness, which is currently framed under the broader term “Deaf and Hard of Hearing” (DHoH) – covers hearing loss that ranges from mild, moderate, severe, and profound – is a relatively common condition and found in all regions and countries, irrespective of gender, social or economic status of individuals. Its typology and etiology are varied.
Maintaining global statistical data on the rates of deafness and hearing impairment global wide is a difficult but necessary task, as this condition is estimated to be the third leading cause of disability by 2050. Information is dispersed and sometimes difficult to access, even in the European country’s frame. The reality of the numbers does not always correspond to the real dimension of the phenomenon of deafness and HoH, as can be seen in the report of the European Federation of Hard of Hearing People [i] (EFHOH, 2015), which that year published statistics on the prevalence of deafness and hearing impairment in Europe, with no known references in countries like Italy and Greece. For many countries, data on the prevalence of hearing loss are not yet available, and the factors associated with hearing loss have not been examined in a detailed manner. This holds true for Russia and Eastern Europe, with an estimated number of 8.7 million Deaf and “Hard of Hearing”, being Russia the country with the highest rate of deafness in the world (Bikbov et al, 2019) [ii].
The importance of demonstrating the increasing numbers of deafness in childhood and adolescence is crucial in the development of awareness strategies and preventive care, due to the strong relationship with the exposure of children and young people to noise levels that are harmful to hearing health. In European countries with approximately 9% of the population, ahead of deafness/hearing impairment prevalence rates are the United Kingdom, Sweden, and the Netherlands. However, the reality of the European population is constantly changing, and we already have a perspective from newcomers from non-Western countries, which impacts the statistics of some European countries, mainly the countries that host displaced deaf people. In Sweden and the Netherlands, there are more and more hearing-impaired and deaf refugee and migrant children as well as their parents, who come from non-Western countries (EFHOH, Kentalis congress Teaching Deaf Learners, 2019) [iii]. The countries with the most developed responses in terms of deaf education tend to receive more displaced deaf people, due to the preparation of education systems and the vocation of professionals and social and health support structures.
When we speak at a global level, we move to a rate close to 20% of the global population, that is, there are currently more than 1.5 billion DHoH people, 430 million of them have disabling hearing loss, with a compromise of what are their rights to schooling, communication, socialization, access to information and well-being. It is expected by the World Health Organization (WHO) that by 2050, there could be over 2.5 billion people with disabling hearing loss and at least 700 million will require hearing rehabilitation (WHO,2022), which in 2050 corresponds to 1 person in each 4 – one of the 3 main causes of disability, especially in older populations [iv]. In Russia, it is primarily or secondarily associated with older age, depression, male gender, cardiovascular disease, and alcohol consumption (Bikbov et al, 2019).
In the paper Global and regional hearing impairment prevalence: an analysis of 42 studies in 29 countries [v], hearing impairment prevalence is positively related in low and middle low-income regions, sub-Saharan Africa, and in South and Southeast Asia (Stevens at al, 2011). In these regions, there are higher rates in both DHoH adults and children. According to Freeland & Mohammed (2010), the conclusions of a study carried out in Tanzania[vi], severe hearing impairment among children and adults in developing countries may have been caused by higher rates of pre-and post-natal childhood infections such as rubella, measles, and meningitis and from the use of ototoxic drugs.
These data corroborate the information available from the World Health Organization about the causes of deafness in different age groups: in the prenatal period, they are related to hereditary and non-hereditary genetic factors and infections in the intrauterine period and in the perinatal period. The etiology of deafness is related to birth asphyxia, low birth weight, neonatal hyperbilirubinemia (or jaundice in newborns), and other comorbidities. Already in childhood and adolescence, factors include ear infections such as recurrent or chronic otitis, meningitis, or other infections. Throughout life, hearing loss develops due to nutritional deficiencies, exposure to excessively noisy environments, auditory trauma, and sequelae by viral action [vii].
In developing countries, children with hearing loss and deafness often do not receive schooling. Adults with hearing loss also have a much higher unemployment rate. Among those who are employed, a higher percentage of people with hearing loss are in the lower grades of employment compared with the general workforce (WHO). In addition to these limitations, low- and middle-low-income countries also bear a disproportionate burden from deafness and hearing loss, in the case of providing assistive technology to DHoH individuals. WHO estimates that global hearing aid production covers just 3% of the need in these countries.
Very high prevalence of child and adult hearing impairment is found in low-income regions [viii], especially in sub-Saharan Africa and in South and Southeast Asia in comparison to other regions. Stevens (2011) found results consistent with deafness rates in India, Indonesia, Madagascar, Myanmar, Nepal, Sri Lanka, and Vietnam but also confirmed that countries like Nigeria have outliers, higher than the official figures state.
However, although hearing loss is preventable throughout the life course, through effective public health interventions for example, in children, almost half of hearing loss is due to causes that can be prevented through measures such as immunization, improved maternal and neonatal care [ix] and early medical treatment of otitis (World report on hearing: executive summary), other situations (approximately the other half of the cases) belong to a different phenomenon from the environmental impact mentioned before: this is the case of congenital deafness. One of the significative causes is related to consanguineous marriage, i.e. descendants of marriage that takes place between close relatives, such as uncles and nephews or between cousins. This marriage, also called “intermarriage” occurs, in this case, within a specific social or cultural group, as required by custom or law (endogamy) or marriage between people belonging to the same small group, especially if they are close blood relatives.
More specific cases such as hereditary congenital deafness due to genetic causes were studied in the medical field by Sheffield and Smith (2019) in The Epidemiology of Deafness, and from an anthropological perspective, such as that studied by Kusters, in the reality of the deaf community in Ghana (2019) [x], West Africa, and Mumbai (2017) [xi] (formerly Bombay), India’s largest city on the country’s west coast. Hereditary deafness is a phenomenon that occurs in some countries and crosses generations due to the presence of consanguinity in marriage: “A relatively high number of deaf people were born there due to the circulation of a recessive gene for deafness through intermarriage” (Kusters, 2019).
This phenomenon is also very present in Egypt, particularly in the northern region. Experts say nearly 5 million of Egypt’s 100 million residents are deaf, due in part to frequent intermarriage of close relatives. The Egyptian Deaf population often struggles with education opportunities, health services, and medical treatment and comes to Cairo from poor and rural areas.
In Abdel-Hamid work: Prevalence and patterns in hearing impairment in Egypt, a national household survey (2007)[xii], it is shown that the prevalence of hearing loss in Egypt (16.02%) is higher than in many other countries, both developed countries such as the United States (9.6%) [10] and developing countries such as Indonesia (4.6%) and Sri Lanka (8.8%). The rate is also higher than that of Oman (5.53%) and Saudi Arabia (13%), which as Arab countries have ethnic, cultural, and traditional similarities to Egypt. Although there is no uniformity in the data collected by Governatore, that is, there are significant statistical differences between the selected regions of Egypt:
The highest rate of hearing loss was found in Marsa Matrouh (25.68%) followed by Alexandria (20.13%) and the lowest in North Sinai (13.51%). These regions belong to the north of Egypt and concentrate the highest rate of cases of childhood deafness.
Previous Egyptian studies have pointed to hereditary and infection as the main etiologies of deafness and hearing loss. It is reported that in the Western literature about 24%–39% of the causes of hearing loss are due to genetic factors. In the work of Snoeckx et al (2005), Mutation Analysis of the GJB2 (Connexin 26) Gene in Egypt [xiii], the authors affirm that the «c.35delG gene mutation» is the most common pathogenic mutation in this population but deafness in Egypt is genetically very heterogenous and that there are large differences between populations. Consanguineous marriages are common in Egypt, most families show a recessive inheritance pattern. In forty-four participant families in the genetic study, the parents were first cousins while in 10 families the parents were second cousins.
However, in the aforementioned survey by Abdel-Hamid et al. (2007) the inflammatory and infectious causes of the middle ear were the most mentioned by the respondents, especially in childhood deafness ´The commonest sequel of acute otitis media is otitis media with effusion with conductive hearing loss’. The authors of this survey argue that whatever the etiology of deafness, all cases can be the focus of preventive action or therapeutic follow-up. The problem often lies in the lack of effective early diagnosis, medical intervention, medication, and the possibility of rehabilitation or cochlear implant surgery.
In many cases, it is a matter of insufficient investment by States in maternal and child health programs, namely in Egypt, considered a “low and low-middle-income” country. An important element that considers Egypt a developing country, despite its increased rates of modernization and industrialization, is the inequality between inhabitants. Wealth, Health, Education and Quality of life in Egypt are not shared equally among the population, especially in comparison with other nations. “Despite all the positives about Egypt’s economic performance, many of the characteristics of a developing country—from pollution and traffic injuries to illiteracy and poverty—are sadly visible across the country. These problems don’t automatically disappear with economic growth, and they take more to solve than just government, or even private, spending”. [xiv]
The health of the ‘ear’ should become a priority in Egypt, with measures led by the Ministry of Health, particularly in public policies on Child Health, Family Planning and in the field of Education, with an emphasis on rural areas, where families are less educated. Deafness is one of the factors with the greatest impact on the school and work absenteeism and, consequently, on limiting participation in communities and psychosocial development. Added to this reality is the need to provide an effective educational response in the field of Deaf Education, supported by up-to-date theoretical references, training of professionals and adequate structures. WHO states that the number of people living with unaddressed hearing loss and ear diseases is unacceptable and estimates that unaddressed hearing loss poses an annual global cost of US$980 billion. This includes health sector costs (excluding the cost of hearing devices), costs of educational support, loss of productivity, and societal costs. 57% of these costs are attributed to low- and middle-low-income countries.
As Dr. Mary Ishaq, who runs the Deaf Unit Cairo school refers, educational challenges have even further intensified during the COVID-19 pandemic and lockdown, which have exposed the fragility of the Egyptian deaf and their families [xv]. Also, new challenges challenged health systems and hopefully focused attention on the need to invest in health care as a means to safeguard the world’s DHoH populations in the future (World report on hearing, WHO, 2021).
[i] European Federation of Hard of Hearing People Report, available at https://efhoh.org/wp-content/uploads/2017/04/Hearing-Loss-Statistics-AGM-2015.pdf.
[ii] Bikbov, M. M., Fayzrakhmanov, R. R., Kazakbaeva, G. M., Zainullin, R. M., Salavatova, V. F., Gilmanshin, T. R., Arslangareeva, I. I., Nikitin, N. A., Panda-Jonas, S., Mukhamadieva, S. R., Yakupova, D. F., Khikmatullin, R. I., Aminev, S. K., Nuriev, I. F., Zaynetdinov, A. F., Uzianbaeva, Y. V., & Jonas, J. B. (2019). Self-reported hearing loss in Russians: the population-based Ural Eye and Medical Study. BMJ Open, 9(3). https://doi.org/10.1136/bmjopen-2018-024644.
[iii] Kentalis Congress Teaching Deaf Learners, available at https://www.efhoh.org/wp-content/uploads/2019/12/Newletter_no_1_2019_version_8.pdf.
[iv] European Federation of Hard of Hearing (EFHOH), available at https://www.efhoh.org/wp-content/uploads/2019/12/Newletter_no_1_2019_version_8.pdf.
[v] Stevens,G., Flaxman,S., Brunskill, E., Mascarenhas, M., Mathers, C., Finucane, M. on behalf of the Global Burden of Disease Hearing Loss Expert Group, Global and regional hearing impairment prevalence: an analysis of 42 studies in 29 countries, European Journal of Public Health, Volume 23, Issue 1, February 2013, Pages 146–152, available at https://doi.org/10.1093/eurpub/ckr176.
[vi] Freeland, A., Jones, J., Mohammed, N.K. Sensorineural deafness in Tanzanian children–is ototoxicity a significant cause? A pilot study, Int J Pediatr Otorhinolaryngol, 2010, vol. 74 (pg. 516-9).
[vii] https://academic.oup.com/eurpub/article/23/1/146/460112
[viii] Data from The World Bank: “For the current 2023 fiscal year, low-income economies are defined as those with a GNI per capita, calculated using the World Bank Atlas method, of $1,085 or less in 2021; lower middle-income economies are those with a GNI per capita between $1,086 and $4,255; upper middle-income economies are those with a GNI per capita between $4,256 and $13,205; high-income economies are those with a GNI per capita of $13,205 or more”.
[ix] World report on hearing, available at https://www.who.int/teams/noncommunicable-diseases/sensory-functions-disability-and-rehabilitation/highlighting-priorities-for-ear-and-hearing-care.
[x] One Village, Two Sign Languages: Qualia, Intergenerational Relationships and the Language Ideological Assemblage in Adamorobe, Ghana, Kusters, A., (2019). Journal of Linguistic Anthropology. Available at https://doi.org/10.1111/jola.12254
[xi] Ishaare: Gestures and Signs in Mumbai, Kusters, A., dir. 75 min. Indian Sign Language, Hindi, English, and Marathi with English subtitles. Mumbai, India: MPI MMG, (2015), available at https://anthrosource.onlinelibrary.wiley.com/doi/abs/10.1111/aman.12965
[xii] Prevalence and patterns in hearing impairment in Egipt, a national household survey (2007), available at https://applications.emro.who.int/emhj/1305/13_5_2007_1170_1180.pdf?ua=1
[xiii] Rikkert et al. (2005). Mutation Analysis of the GJB2 (Connexin 26) Gene in Egypt, available at https://onlinelibrary.wiley.com/doi/epdf/10.1002/humu.9350
[xiv] Why is Egypt a Developing Country? Available at https://www.cibeg.com/en/learning-center/economics-101/why-egypt-is-a-developing-country
[xv] VOA- Egypt School for the Deaf Works Against Odds to Educate Children, available at https://www.voanews.com/a/middle-east_egypt-school-deaf-works-against-odds-educate-children/6204112.html
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Filipa Machado Rodrigues (9 de Outubro de 2022). Low and middle-low-income world economies lead the deafness ranking. Desenvolvimento Humano Integral. Recuperado em 26 de Janeiro de 2025 de https://doi.org/10.58079/nkv9