Prevalence and associated risk factors of respiratory diseases among residents of Tsumeb locality of Namibia.

Abstract

Respiratory infections represent a major global health problem, and occurrences of respiratory diseases have been increasing in Southern Africa countries including Namibia due to anthropogenic activities. This study was conducted in Tsumeb, a municipal township located in the Northern part of Namibia. It aimed at determining the prevalence of respiratory ailments among the residents, identify risk factors associated with the prevalence and recommend appropriate measures to prevent exposure of residents to identified risk factors. A combination of experimental and descriptive cross-sectional quantitative approach was adopted in the data collection process. Interviewer-administered questionnaires were presented to respondents for the purpose of data collection on exposure, prevalence and health impacts of respirable dusts on their health. Analysis of heavy metals in collected respirable dust from twelve (12) households was also carried out. Heavy metals were extracted from the dust samples using mineral acid digestion protocol. Qualitative and quantitative analysis of the metals was done by use of the Inductively-Coupled Plasma Optical Emission Spectroscopy (ICP-OES). From the results obtained, 66% of respondents indicated that the roads that passes by their houses were tarred, 91% reside in single storey dwellings while 78% indicated that the windows of their houses were not protected from the passage of respirable dusts. The 65% of responders confirmed that they noticed changes in the quality of air. About 25.5% of respondents affirmed that reduced air quality may affect their health and possibly lead to other respiratory ailments such as difficulty in breathing, nasal congestion and running nose. Severe coughing was reported to be experienced by 79.5% of respondents. From the heavy metal analyses, metallic values in the analysed respirable dust samples ranged from 72 – 713.4, 0 – 18.0,1.66 – 15.8,14.15– 2338.3,68.9– 1616.6 and 6.86– 897.9 mg/kg for Mn, Cd, Ni, Cu, Zn and Pb respectively. Zinc (Zn) recorded the highest metallic value while Ni recorded the lowest value. Most of the analysed heavy metals were above the acceptable limit with the exception of Ni. Identification of respiratory risk factors is important for the prevention of exposure and development of health problems. Research findings have clearly showed that residents are exposed to respiratory disease risk factors such as poor air quality, air-borne respirable dust that are laden with toxic heavy metals and residual cigarette smoke. Regular monitoring of air quality in the locality, prevention of the release of heavy metals as a result of anthropogenic activities and sensitization of residents of the need to install appropriate air net on windows and doors of their residences in order to prevent the passage of respirable dust are recommended.