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,
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
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
Malaria programme at Obuasi
When fully implemented by 2005, the integrated malaria control programme will consist of the following activities:
Indoor residual house spraying with an organophosphate insecticide, in the first instance, will form the main thrust of the programme and to be effective, all of the estimated 40,000 houses in Obuasi need to be sprayed. This represents a major logistical challenge. In addition to house spraying, window and door screens need to be installed. The use of insecticide impregnated bednets (ITNs) will be promoted and subsidies to make bednets affordable to the community will be investigated. Environmental control efforts such as focused larvicidal spraying and engineering controls to ensure the reduction of open water bodies in the Obuasi district will augment the residual spraying campaign.
Effective treatment protocols, which comply with national guidelines, have been introduced at
AngloGold Ashanti's William Cade Hospital (the local hospital at Obuasi) as chloroquine is no longer an effective drug in the treatment of malaria due to the development of significant drug resistance by the Plasmodium parasite. In addition to ensuring acceptable cure rates for malaria, effective drug treatment will reduce the pool of infected individuals in the community thereby impacting on the transmission cycle of malaria. Stricter criteria for the clinical diagnosis of malaria have been introduced which
will improve the quality of case reporting and enable the health service to accurately track malaria incidence trends over time.
Surveillance and monitoring
A malaria information system will measure programme outcomes in the light of established standards and will consist of a database containing information on, for instance, insecticide resistance, larval surveys, bioassays, drug resistance, case detection, house spraying coverage, insecticide usage, bednet distribution and usage, breeding sites, disease outbreak foci, house screening and geographic information systems. The computerised system to be underpinned by field documentation will ensure that all the relevant data is captured at source.
Information, education and communication
Spray teams and medical staff have been trained to provide health information to the general population on aspects of malaria prevention, diagnosis and treatment.
This will be augmented by the provision of educational material such as pamphlets, posters and videos on malaria. Personal protective measures against malaria will also be promoted.