Academic literature on the topic 'Deafness, Noise induced – Namibia'

Introduction: Noise is a health risk that cannot be avoided in production process. Noise has the potential to cause hearing loss for workers. The bad news, noise damage due to noise is permanent. Audiometric screening at shipyard company employees found 81.2% experienced Sensory-Neural Hearing Loss. 61.5% of employees experience deafness in both ears. The research objective was to find the cause of deafness at shipyard company. Methods: A Quantitative research with cross sectional approach in 64 subjects who worked in the ship repair production unit. The sample is chosen with a simple random technique according to inclusion and exclusion criteria. Assessment was carried out using questionnaires, measurement, and direct observations. Result: The bad habit of wearing ear protectors on employees as a cause of deafness (p<.001, Coef .517**). Sound level measurement shows the activity of chipping, welding, cutting and outfitting with noise intensity more than the recommended threshold (85 dBA for 8 hour per day). Noisy sources were found such as blowers, compressors, grinders, cutting mach ines, ringlet machines, hammer blows on plates and generators. Conclusion: Hearing loss in shipyard company employees is a work-related disease caused by the poor culture of wearing ear protectors. The habits does not wear earplug/earmuff tools because its not comfortable in the ear when the appliance is used, the tools too small so its easily lost, forgetten to carry, and tool are not available.

Introduction: Noise is a health risk that cannot be avoided in production process. Noise has the potential to cause hearing loss for workers. The bad news, noise damage due to noise is permanent. Audiometric screening at shipyard company employees found 81.2% experienced Sensory-Neural Hearing Loss. 61.5% of employees experience deafness in both ears. The research objective was to find the cause of deafness at shipyard company. Methods: A Quantitative research with cross sectional approach in 64 subjects who worked in the ship repair production unit. The sample is chosen with a simple random technique according to inclusion and exclusion criteria. Assessment was carried out using questionnaires, measurement, and direct observations. Result: The bad habit of wearing ear protectors on employees as a cause of deafness (p<.001, Coef .517**). Sound level measurement shows the activity of chipping, welding, cutting and outfitting with noise intensity more than the recommended threshold (85 dBA for 8 hour per day). Noisy sources were found such as blowers, compressors, grinders, cutting mach ines, ringlet machines, hammer blows on plates and generators. Conclusion: Hearing loss in shipyard company employees is a work-related disease caused by the poor culture of wearing ear protectors. The habits does not wear earplug/earmuff tools because its not comfortable in the ear when the appliance is used, the tools too small so its easily lost, forgetten to carry, and tool are not available.

Thesis (MAud)--Stellenbosch University, 2015.
ENGLISH ABSTRACT: In developing countries, like Namibia, there is limited data pertaining to the number of individuals with hearing loss and its associated factors. This study aimed to determine the prevalence of potential hearing loss in Namibian Class A mines and to describe the extrinsic and intrinsic factors associated with hearing loss. A cross-sectional design was utilised and data were collected from 132 respondents (mining employees) from five different Class A mines throughout the country. A questionnaire and a retrospective review of respondents’ medical records were utilised to determine the risk factors. The most recent audiogram found in the respondents’ records was used to determine the presence of potential hearing loss. Three definitions of potential hearing loss were used in this study and included all major frequency hearing loss (AFHL), high frequency hearing loss (HFHL) and low frequency hearing loss (LFHL). Potential hearing loss was identified when the pure tone average (PTA) of 0.5, 1, 2, & 4kHz, 0.5, 1 & 2kHz and 4 & 8kHz respectively was greater than 25dBHL in either one or both ears. Chi-square measurements or, where necessary, Fisher’s exact tests, as well as Odds Ratios were used for the analysis of data. In general a significance level of 5% was applied for all analyses. Results indicated the prevalence of potential hearing loss in Namibian mining employees to be 27% and that both extrinsic and intrinsic factors were associated with hearing loss. The extrinsic factors significantly associated with potential hearing loss were both occupational and medical. The occupational factors found to be significant were the number of years employed in whole life >10 years (p=0.012; OR=3.1, 95% CI=1.3-7.9), the number of years employed in current job > 10 years (p=0.01; OR=3.9, 95% CI1.7-8.8) and the non-availability of formal training in prevention of hearing loss (p=0.022; OR=0.3, 95% CI (0.1-0.9). Diabetes was the sole significant extrinsic medical factor (p=0.035, OR=5, 95% CI 1.1-22.1). The only intrinsic factor which was found to be significantly associated with hearing loss was Age, specifically being older than 40 years (p=0.002; OR=3.5, 95% CI 1.6-7.8) and 50 years (p=0.001, OR=5.5, 95% CI1.9-15.8). A multiple logistic regression model of all significant factors found that only no formal training of prevention of hearing loss was found to be significant in the presence of all other factors (p=0.036, OR=0.036, 95% 0.1-0.92). Findings from this study suggest that multiple factors may be associated with potential hearing loss and not just the exposure to hazardous occupational conditions. Recommendations for future research and clinical practice should, therefore, include thorough investigations into the aetiology of hearing loss. As this study focused on Class A mines, it is recommended that future research be conducted in other mines that are not categorised as Class A mines. Keywords: prevalence, extrinsic factors, intrinsic factors, extrinsic occupational factors, extrinsic social factors, extrinsic medical factors, potential hearing loss, mining industry, Class A mine, Namibia.
AFRIKAANSE OPSOMMING: In ontwikkelende lande, soos Namibië, is daar beperkte data met betrekking tot die aantal individue met gehoorverlies en sy verwante faktore. Hierdie studie het gepoog om die voorkoms van gehoorverlies in Namibiese Klas A myne te bepaal en die ekstrinsieke en intrinsieke faktore wat verband hou met potensiale gehoorverlies te beskryf. 'n Deursnee-ontwerp is gebruik en data is ingesamel uit 132 respondente (mynbou werknemers), uit vyf verskillende Klas A myne regdeur die land. 'n Vraelys en 'n retrospektiewe oorsig van die respondente se mediese rekords is gebruik om die risiko faktore te bepaal. Die mees onlangse oudiogram wat in die respondente se rekords gevind is, is gebruik om die teenwoordigheid van potensiale gehoorverlies te bepaal. Drie definisies van potensiale gehoorverlies is gebruik in hierdie studie, ingesluit al die groot frekwensie gehoorverliese (AFHL), hoë frekwensie gehoorverlies (HFHL) en 'n lae frekwensie gehoorverlies (LFHL). ‘n Gehoorverlies was teenwoordig wanneer die suiwer toon gemiddelde (PTA van 0.5 , 1 , 2, & 4kHz , 0.5, 1 & 2kHz en 4 & 8kHz onderskeidelik , groter was as 25dBHL in een of albei ore. Chi -square metings of, waar nodig, Fisher se presiese toetse, asook kans verhoudings is gebruik vir die ontleding van data. In die algemeen is 'n beduidendeidsvlak van 5% gebruik en toegepas vir al die ontledings. Resultate het aangedui die voorkoms van gehoorverlies in Namibiese mynbouwerknemers tot 27 % was en dat beide ekstrinsieke en intrinsieke faktore ‘n verband toon met potensiaal gehoorverlies. Die ekstrinsieke faktore wat ‘n beduidende verband getoon het met gehoorverlies was albei beroeps- en mediese faktore. Die beroepsfaktore wat betekenisvol was, was die aantal jare diens in hele lewe > 10 jaar ( p = 0,012 ; OR = 3.1 , 95 % CI = 1.3-7.9) , die aantal jare in huidige pos> 10 jaar diens (p = 0,01 ; OF = 3.9 , 95 % CI1.7-8.8 ) en die onbeskikbaarheid van formele opleiding in die voorkoming van potensiaal gehoorverlies (p = 0,022 ; OF = 0,3 , 95 % CI ( 0,1-0,9 ). Diabetes was die enigste beduidende ekstrinsieke mediese faktor (p = 0,035 , OR = 5 , 95 % CI 1,1-22,1 ). Die enigste intrinsieke faktor watbeduidend was en verband hou met gehoorverlies was ouderdom, spesifiek om ouer as 40 jaar ( p = 0,002 ; OF = 3.5 , 95 % CI 1,6-7,8 ) en 50 jaar ( p = 0.001 , OR = 5.5 , 95 % CI1.9-15.8 ) te wees. 'n Veelvuldige regressie model van alle beduidende faktore het bevind dat slegs geen formele opleiding in die voorkoming van gerhoor verlies beduidende was in die teenwoordigheid van al die ander faktore ( p = 0,036 , OR = 0,036 , 95 % 0,1-0,92 ) . Bevindinge van hierdie studie dui daarop dat verskeie faktore geassosieer kan word met gehoorverlies en nie net die blootstelling aan gevaarlike beroepstoestande nie. Aanbevelings vir toekomstige navorsing en kliniese praktyk moet dus 'n grondige ondersoek na die etiologie van gehoorverlies uitvoer. Aangesien hierdie studie gefokus het op die Klas A- myne , word dit aanbeveel dat toekomstige navorsing gedoen word in ander myne wat nie gekategoriseer is as Klas A myne nie. Sleutelwoorde: Voorkoms, ekstrinsieke faktore, instrinsieke faktore, ekstrinsieke beroepsfaktore, ekstrinsieke sosiale faktore, ekstrinsieke mediese faktore, potensiale gehoorverlies, Klas A myn, Namibië.

Children suffering from noise-induced hearing loss could have disease burden such as communication difficulties, frustration, isolation as well as impaired self-cognition due to different degrees of hearing loss. Lack of hearing protection was the easiest way to tackle among the risk factors. Hence, the aim of this review is to review and synthesize existing evidence to show the effects of hearing conservation programs targeted on children and adolescents. Six studies included meeting strict requirements of inclusion and exclusion criteria. Significant improvements were shown in knowledge, attitude, intended behavior as well as hearing protective devices use regarding educational programs. However, limited effective consequence was shown in terms of audiometric threshold testing, thus, indicating limited effectiveness of educational programs in noise-induced hearing loss prevention. The results of hearing conservation programs were illustrated in details. And limitations as well as implications were discussed.
published_or_final_version
Medicine
Master
Master of Public Health

At-risk hearing conditions in various aerobic classes in different gymnasiums were identified and the hearing of aerobic class goers monitored to provide information for an improved understanding of noise-induced hearing loss. Hearing levels were monitored over time for four comparison groups, including regular attendees of aerobic classes with an average noise level above 85 dBA (“High-Risk” group), regular attendees of aerobic classes with an average noise level below 85 dBA (“Low-Risk” group), non-gym goers attending one “High-Risk” aerobic class with hearing protection (“Control with HP” group), and non-gym goers attending one “High-Risk” aerobic class without hearing protection (“Control without HP” group). Each comparison group consisted of three to five males and three to five females, aged between 18 to 50 years. Measurements of pure-tone audiometry (PTA) and distortion product otoacoustic emissions (DPOAEs) were obtained from before and immediately after participation in one class and 48 hours and 30 days after the initial test. Noise levels in many aerobic classes (77%) were found to be higher than 85 dBA and might have led to signs of hearing deterioration as shown mostly in the reduction of the activities of outer hair cells and sometimes in the shift of hearing threshold. The “High-Risk” group exhibited the largest reduction of DPOAEs amplitudes over time. The “Control without HP” group generally exhibited a larger degree of reduction in DPOAEs amplitudes immediately after exposure as compared with the “Control with HP” group. Measurement of DPOAEs levels appeared to be a more sensitive tool than PTA in detecting early signs of hearing deterioration related to noise exposure.

Background: Noise is one of the most important forms of environmental pollution among developed and developing countries. A report from UK National Study of Hearing estimated that around 440 million people suffer from noise induced hearing loss in EU countries with 1–1.6 million disability-adjusted life year lost. In China, the Second China National Sample Survey on disability in 2007 revealed that about 27.8 million people suffered from hearing impairment, and 73.4% of which (about 20 million) were diagnosed with disability. The prevalence of hearing impairment was estimated to be 2.1% in the general population, and increased to 11.0% among those aged greater than 65 years. Objective: To find out the effect of earplug on noise induced hearing loss (NIHL), as well as understanding the source and exposure of noise in the industry, to estimate the prevalence of NIHL in factories with noise exposure, to analyze relationships between NIHL and age, sex, dose and duration of occupational noise exposure, type of work, use of hearing protection products, education level and other factors. Significant risk factors identified were used to provide evidence-based recommendations in prevention and control of NIHL. Study Design: Retrospective, cross-sectional study Method: A total of 1874 workers exposed to noise in a compressor factory in Guangzhou, China were included. Between September 2011 and January 2012, physical examination including a screening program of hearing loss, pure tone audiometry test were carried out among workers including information on age, sex, work types, noise exposure level, exposure time, as well as the questionnaire about earplug using status, status of using ear products report by company, smoking status, education level, discharge of ear, history of herpes zoster, history of using ototoxic drugs, history of ear surgery, family history of NIHL, systolic blood pressure, diastolic blood pressure. The outcome variable is the audiometric mean value which reflects hearing status of the subjects. Subgroup differences in mean value of audiometry were compared by independent sample t-test. Multiple linear regression and logistic regression models were used to evaluate associations between earplug use and NIHL, adjusted for other potential confounders. Factors associated with earplug use were also identified. Result: 1873 workers took part in the study (both physical examination and questionnaire) The prevalence of NIHL is 381 (20.3%) from study, and an average noise level of 83.5 dB was detected in the factory across different types of working place. The pure tone audiometric mean value (PTA) is 26.7 dB with a standard deviation of 4.8. The mean PTA value for those using earplug is 25.81 dB, which was significantly lower than those not using earplug with a mean PTA value of 1.54 dB (p < 0.001). A 0.962 mean difference is detected between noncontinuous earplug usage group and continuous usage group. Multiple linear regression model showed a dose response effect in use of earplug on NIHL, with an estimated mean PTA 1.49 dB (p-value <0.001) and 0.96 dB (p-value = 0.001) lower than those not using earplug at all. Hearing protective effect with part of dose response relationship is found in education level groups as well. Workers from technical school have a 5.974 dB lower of mean PTA, where the decrease is 3.909 dB in high school group, reference of primary level. Moreover, ever smokers show 1.557 dB higher on reference as nonsmoker. Other significant results can be found in family history of NIHL, ototoxic drug using, with statistical significant, respectively, with the direction of positive to NIHL, which shows harmful effect on workers’ hearing. Multivariable logistic regression model is used to find out factors associated with earplug usage. In the model, higher education level is found to be associated with higher earplug usage, especially among participants from technical schools, with an adjusted odds ratio (AOR) of 34.07, whereas those from high school group have an AOR of 12.35.(With Primary school group being the reference group.) Workers whose daily tasks involve phosphorus board, punching press, compressor are found to have a relatively low percentage on earplug usage compliance, with AOR of 0.55, 0.41, 0.23 respectively. (Those from machine shops are used as the reference group.) The result is in accordance with their positive correlation on NIHL. Conclusion: Use of earplug was found to be protective to NIHL. Factors such as education level, smoking status, discharge of ear, family history of NIHL and certain types of work were found to be associated with lower risk of NIHL. To protect hearing of the workers and reduce NIHL prevalence, provision of and education on hearing protection products and supervision of continuous use of earplug in noise exposed industry should be implemented. Occupational health monitoring to the enterprises should be enhanced by health sectors of Chinese government. Due to the limitation of retrospective design of this dissertation, further cohort studies are called for to provide stronger evidence of factors’ effect on NIHL.
published_or_final_version
Public Health
Master
Master of Public Health

Thesis (M. Sc.) -- University College London, 1998.
A project submitted (to the Institute of Laryngology and Otology) as a requirement for the degree of Master of Science in Audiological Medicine, University College London. Bibliography: leaves 83-101.

This chapter outlines ear, nose and throat diseases. It includes ENT examination, prevalence of ENT symptoms, the ear, audiology, painful ears, discharging ears, fluid in the middle ear, childhood deafness, cochlear implants, deafness in adults, tinnitus, acoustic neuroma, noise induced hearing loss, vertigo, rhinosinusitis and nasal polyps, the paranasal sinuses, nasal injury and foreign bodies, nosebleed (epistaxis), throat infections, stridor, acute airway obstruction, hoarseness, laryngeal nerve palsy, head and neck cancers, dysphagia, facial palsy, lumps in the neck, the salivary glands, dry mouth (xerostomia), and dentistry for doctors.

This chapter in the Oxford Handbook of Clinical Specialties explores the ear, nose, and throat (ENT) specialty. It outlines examination in the ENT in general and investigates each area in depth. The ear is explored including hearing tests, painful ears (otalgia), discharging ears, otitis media, and fluid in the middle ear. Deafness in childhood and adults is discussed, as well as tinnitus, acoustic neuroma, noise-induced hearing loss, and vertigo. The nose is explored, including the paranasal sinuses, nasal injury, foreign bodies, and nosebleed. The throat is investigated, including sore throat, stridor, hoarseness (dysphonia), dysphagia, cancer, palsy, neck lumps, and salivary glands. Dentistry for doctors is also explored.