HIV/AIDS and Malaria

AngloGold Ashanti is poised to implement a multi-million dollar malaria control campaign in Ghana, following initial valuable research to understand the nature of the disease in the region.

Says Dr Piet van Wyk, (AngloGold Health Service manager: Africa Region), "Malaria is the single most important disease to impact on AngloGold Ashanti's operations in East and West Africa. The burden of malaria is reflected in increased morbidity, mortality and absenteeism in the workforce, as well as in decreased productivity and morale. The effect of malaria on surrounding non-mine communities is profound, with children and pregnant women being most severely compromised by this life-threatening parasitic disease."

The situation at Obuasi in the Ashanti region of West Ghana is no different and at the time of the business combination with Ashanti in April 2004, upwards of 6,000 malaria cases per month were being reported by the mine medical service. At any one point in time, 20% of the workforce had malaria and the average time off work for this condition was between two and three days. If these trends are extrapolated to the broader Obuasi community of 150,000 people, the full impact of the epidemic in this region can be appreciated.

As a starting point, the group needed to establish a scientific foundation on which to approach the problem, so a baseline study was initiated to identify resident mosquito vector species and possible insecticide resistance patterns in these populations. Professor Richard Hunt of the National Institute of Communicable Diseases in South Africa, a world authority on insecticide resistance, was contracted to perform the study.

The outcome of the study is now informing the way in which the malaria control programme is being structured: two dominant Anopheles mosquito species were identified, namely funestus and gambiae. Both of these species are effective in transmitting malaria and subsequent laboratory investigations in Johannesburg confirmed significant infection in both vectors with the malaria parasite, Plasmodium falciparum.

The insecticide resistance patterns in both species proved to be complex with complete, or partial resistance to three of the standard insecticides endorsed by the World Health Organization (WHO) for use in malaria control. However, both mosquito vectors were found to be susceptible to the organophosphate class of insecticides. Based on this knowledge an integrated malaria control approach was required as none of the recognised malaria control measures used in isolation would be effective in the Obuasi setting.

Says Dr Van Wyk, "Prior to implementing the full control programme, a baseline community parasite prevalence study will be performed by the Noguchi Research Institute in Accra. The baseline parasite prevalence rate will be used in follow-up studies to assess the success of local control initiatives.

In conjunction with the prevalence study, a community knowledge, attitudes and practices survey will be conducted in Obuasi to inform a programme intended to disseminate information on malaria prevention and treatment as well as to market the the control programme. Periodic surveillance of mosquito species and insecticide resistance patterns will enable us to adapt our programmes in response to changes in any of the baseline parameters. A malaria laboratory will be established at Obuasi for this purpose in addition to maintaining captive mosquito colonies for use in quality assurance bioassays of insecticide efficacy.

We aim to reduce the number of malaria cases in the community by 50% one year after the implementation of residual house spraying, scheduled to start in September 2005. We also aim to reduce the number of working days lost due to malaria from the current 3,600 per month to less than 1,000 days per month among the 6,500 employees at Obuasi.

An effective malaria control programme at Obuasi will hold benefits not only for employees in Obuasi, but for society at large. It will have a positive impact on the health status, treatment costs, school attendance and productivity within the community."