Abstract

A recent qualitative investigation in Eswatini (formerly Swaziland) examined the prevalence of occupational exposure to respirable crystalline silica among mineworkers and the associated incidence of silicosis. A systematic review and narrative synthesis were undertaken over three years drawing on 950 peer-reviewed sources and authoritative datasets. Multiple qualitative research methods were employed to interrogate the central hypothesis that no validated quantitative or qualitative evidence currently exists to reliably estimate the burden of silicosis or silica-related diseases in Eswatini.

The review identified substantial gaps in national data, rendering quantitative analysis unfeasible. In particular, the high burden of tuberculosis (TB) and frequent misdiagnosis of silicosis as TB significantly obscure disease detection and reporting. Findings further highlighted the complex interaction of co-infections and co-morbidities associated with Eswatini’s well-documented triple burden of disease: Human Immunodeficiency Virus (HIV), TB, and malaria. The country has the highest HIV prevalence globally at 24.8%, though prevalence among mineworkers was slightly lower at 20%.

Analysis of available evidence suggested the presence of a fourth critical disease pathway for oscillating migrant mineworkers, representing a potential quadruple high-risk burden. TB prevalence in this population was estimated at 5,000 per 100,000—substantially higher than the national prevalence of 733 per 100,000. While silicotuberculosis was identified as a probable consequence of prolonged silica exposure, current data were insufficient to establish its prevalence.

Overall, these findings are consistent with major reports produced by international bodies such as the World Health Organization (WHO) and the International Labour Organization (ILO). The study underscores the urgent need for robust, targeted quantitative research to address identified data deficiencies. Such work is underway and is expected to support improved surveillance, diagnosis, and policy development for silica-associated occupational diseases in Eswatini.