Preventive malaria treatment for contacts of patients with Ebola virus disease in the context of the west Africa 2014-15 Ebola virus disease response: an economic analysis.

Background: After the detection of an Ebola virus disease outbreak in west Africa in 2014, one of the elements of the response was to contact trace and isolate patients in specialised Ebola treatment units (ETUs) at onset of fever. We aimed to assess the economic feasibility of administering preventive malaria treatment to all contacts of patients with Ebola virus disease, to prevent the onset of febrile malaria and subsequent admission to ETUs.

Methods: We used a decision tree model to analyse the costs of preventive malaria treatment (artemisinin-based combination treatment [ACT]) for all contacts of patients with Ebola virus disease (in terms of administration and averted ETU-stay costs) and benefits (in terms of averted ETU admissions) in west Africa, from a health-care provider perspective. The period of analyses was 1 year, which is roughly similar to the duration of the 2014-15 west Africa Ebola outbreak response. We calculated the intervention's cost per ETU admission averted (average cost-effectiveness ratio) by season (wet and dry), country (Liberia, Sierra Leone, and Guinea), and age of contact (<5 years, 5-14 years, and ≥15 years). We did sensitivity analyses to assess how results varied with malaria parasite prevalence (in children aged 2-10 years), daily cost of ETU stay (for Liberian malaria incidence levels), and compliance and effectiveness of preventive malaria treatment.

Findings: Administration of ACTs to contacts of patients with Ebola virus disease was cost saving for contacts of all ages in Liberia, Sierra Leone, and Guinea, in both seasons, from a health-care provider perspective. In the wet season, preventive malaria treatment was estimated to reduce the probability of a contact being admitted to an ETU by a maximum of 36% (in Guinea, for contacts aged <5 years), and a minimum of 10% (in Guinea and Sierra Leone, for those aged ≥15 years). Assuming 85% compliance and taking into account the African population pyramid, the intervention is expected to be cost saving in contacts of all age groups in areas with malaria parasite prevalence in children aged 2-10 years as low as 10%. In Liberia during the wet season, malaria preventive treatment was cost saving even when average daily bed-stay costs were as low as US$5 for children younger than 5 years, $9 for those aged 5-14 years, and $22 for those aged 15 years or older.

Interpretation: Administration of preventive malaria treatment to contacts of patients with Ebola virus disease should be considered by public health officials when addressing Ebola virus disease outbreaks in countries and seasons where malaria reaches high levels of transmission.

Funding: Centers for Disease Control and Prevention.