Cost-effectiveness analysis of use of RDT, microscopy and clinical examination/history in the diagnosis and treatment of malaria, Implications for ACT treatment Policy in Nigeria

Presenter: Benjamin Uzochukwu, University of Nigeria

Abstract

Background

Malaria remains a major cause of morbidity and mortality in Nigeria. The diagnosis and treatment is often based on the clinical presentation of malaria symptoms and microscopy examination of blood films. Treatment based on clinical diagnosis (presumptive treatment) has been found to be unreliable. On the other hand, microscopic diagnosis of malaria is time-consuming and labour-intensive and there is lack of trained microscopists and reliable equipment in Nigeria especially in rural areas. Various rapid diagnostic tests (RDTs) have improved malaria diagnosis in the field. Despite this improvement the cost effectiveness of use of this new diagnostic option in malaria endemic communities in Nigeria remains uncertain.

Objectives.

To generate new policy and relevant knowledge about the relative cost-effectiveness of RDTs when compared to usual methods for diagnosing malaria (presumptive treatment and microscopy in South-east Nigeria.

Methods

A total of 638 patients with fever (presumptive malaria) attending primary health centers in Enugu east Local government area southeast Nigeria were recruited for examination with RDT and microscopy and questionnaire survey. Decision tree model and probabilistic sensitivity analysis was applied to these patients. Costs and effects encompassed those for both patients positive on RDT and who received artemisinin-based combination therapy (ACT) and febrile patients negative on RDT who received an antibiotic treatment. Cost-effectiveness estimates were done using TreeAge programme. Interventions were defined as cost-effective if they were less costly and more effective or had an incremental cost per disability-adjusted life year averted of less than US$ 150. Data were drawn from published and unpublished sources, supplemented with expert opinion.

Results

Out of 638 patients recruited, 275 (43.1%) had microscopic examination (gold standard) of blood smear positive for malaria parasites, 238 (37.3%) were positive for RDT, 224 (35.1%) were positive for both microscopy and RDT, 13 (2.04%) were positive for RDT but negative for microscopy, 49 (7.7%) were positive for microscopy but negative for RDT and 352 (55.2%) were negative for both microscopy and RDT.

The cost-effectiveness analysis at 43.1% malaria prevalence level showed an incremental cost effectiveness ratio (ICER) of 221 per deaths averted between RDT and presumptive treatment while microscopy is dominated at that level. The text report at this prevalence level showed a lesser cost of RDT (337466) compared to presumptive treatment (365426) and microscopy (394246) with effectiveness values of 99862, 99735 and 99851 for RDT, presumptive treatment and microscopy respectively. Cost-effectiveness is also affected by malaria prevalence level, ACT adherence level, cost of ACT, proportion of Non Malaria Febrile Illness (NMFI) cases that were bacterial and microscopy and RDT sensitivity.

Conclusions

At the prevalence level of 43.1% RDT will be a preferred strategy for diagnosis of malaria in Nigeria. But there is the need to ensure that patients adhere to the treatment procedures. It is also necessary to improve on health budget and expenditure that aim at further reducing the cost and non-accessibility of RDT at all levels of healthcare in Nigeria.