Diamond exploration, malaria and HIV in Angola

Introduction
Diamond exploration in Angola presents infectious disease challenges for both expatriate and local workers. Utilising the Occupational Health infrastructure, De Beers Exploration, in collaboration with a non-government organisation, CONSAUDE, conducted research and introduced measures to manage malaria and HIV, the main infectious challenges in the working population and surrounding community. Both diseases are included in the occupational health surveillance as occupational or chronic manageable diseases.

Methods
A burden of malaria study was conducted on all 176 employees; rapid malaria test results were compared with thick and thin smears examined at the National Institute of Communicable Diseases reference laboratory in South Africa. A vector study was carried out to determine the endemicity of malaria in the camp and adjacent village and the insecticides being used for residual spraying were were evaluated for efficacy. HIV awareness education, and voluntary counselling and testing were conducted for employees to assess the prevalence of HIV and need for treatment.

Results
The burden of malaria study indicated a 2.3% prevalence of asymptomatic P. falciparum. The vector study indicated the presence of A.gambiae and Culex mosquitoes both of which were sensitive to insecticides in use. The HIV prevalence rate was 2.56%

Discussion
Both the malaria prevention and HIV campaigns have been extended to the families of permanent staff in collaboration with CONSAUDE. A process of collaboration with the Angolan Department of Health has resulted in antiretroviral therapy being made available for the Angolan employees and families. Although current insecticides were effective, new products were identified for widespread indoor residual spraying. Managing and mitigating these risks are integral to the business model of De Beers Exploration. The research and interventions were tailored to suit the potentially transient nature of exploration so that sustainable solutions were found to risks such as malaria and HIV.