The Cost of Annual versus Biannual Community-Directed Treatment of Onchocerciasis with Ivermectin: Ghana as a Case Study

Background It has been proposed that switching from annual to biannual (twice yearly) mass community-directed treatment with ivermectin (CDTI) might improve the chances of onchocerciasis elimination in some African foci. However, historically, relatively few communities have received biannual treatments in Africa, and there are no cost data associated with increasing ivermectin treatment frequency at a large scale. Collecting cost data is essential for conducting economic evaluations of control programmes. Some countries, such as Ghana, have adopted a biannual treatment strategy in selected districts. We undertook a study to estimate the costs associated with annual and biannual CDTI in Ghana. Methodology The study was conducted in the Brong-Ahafo and Northern regions of Ghana. Data collection was organized at the national, regional, district, sub-district and community levels, and involved interviewing key personnel and scrutinizing national records. Data were collected in four districts; one in which treatment is delivered annually, two in which it is delivered biannually, and one where treatment takes place biannually in some communities and annually in others. Both financial and economic costs were collected from the health care provider's perspective. Principal Findings The estimated cost of treating annually was US Dollars (USD) 0.45 per person including the value of time donated by the community drug distributors (which was estimated at USD 0.05 per person per treatment round). The cost of CDTI was approximately 50–60% higher in those districts where treatment was biannual than in those where it was annual. Large-scale mass biannual treatment was reported as being well received and considered sustainable. Conclusions/Significance This study provides rigorous evidence of the different costs associated with annual and biannual CDTI in Ghana which can be used to inform an economic evaluation of the debate on the optimal treatment frequency required to control (or eliminate) onchocerciasis in Africa.
Author Summary The African Programme for Onchocerciasis Control (APOC) has recently been extended until 2025, with renewed commitment towards onchocerciasis elimination. This aim is aligned with the goals stated by the World Health Organization and the London Declaration on Neglected Tropical Diseases in January 2012. Switching from annual to biannual (twice yearly) ivermectin distribution might increase the feasibility of onchocerciasis elimination in some African foci. However, relatively few communities have received biannual treatments in Africa, and there are no cost data associated with increasing ivermectin treatment frequency at a large scale, essential pre-requisites to provide reliable information for evidence-based decision making regarding adoption of a biannual treatment strategy. Therefore, we undertook a study to estimate costs associated with biannual compared to annual ivermectin delivery in Ghana, which since 2009 has implemented a biannual treatment strategy in selected priority areas. Our results indicate that the cost of biannual ivermectin treatment per year is approximately 60% higher than the cost of annual treatment. This study provides tangible evidence of the different costs associated with annual and biannual ivermectin treatment, which can be used to inform economic evaluations and policy decisions regarding the optimal treatment frequency required to eliminate onchocerciasis in Africa.