Predictors of treatment failure rates in refugee populations with malaria
DOI:
https://doi.org/10.5281/zenodo.22811763Keywords:
malaria, treatment failure, refugees, artemisinin resistance, displaced populationsAbstract
Background: Malaria treatment failure in refugee and displaced populations is often attributed to drug resistance, but resistance is only one of several predictors that plausibly operate at once in humanitarian settings.
Objective: This review synthesizes the genetic, diagnostic, drug-quality, and access-related evidence bearing on treatment failure in refugee populations with malaria.
Methods: We synthesized clinical efficacy, molecular surveillance, and humanitarian health literature, prioritizing PCR-corrected studies in refugee, border, or conflict-affected populations, using mobile-population cohorts as the closest proxy where camp data were unavailable.
Findings: Parasite resistance, principally kelch13 and partner-drug markers, sets a geography-dependent ceiling on failure, highest along the Thai-Myanmar and Thai-Cambodian borders and only recently emerging in East and Central Africa [7,10]. pfhrp2/pfhrp3 deletion inflates apparent failure independent of resistance in overlapping regions [17]. Drug quality, malnutrition, incomplete adherence, and access interruptions each raise failure independent of genotype [19,20,21].
Conclusions: Treatment failure reflects the simultaneous operation of resistance, diagnostic reliability, drug quality, host status, and access; distinguishing among them before assuming resistance should guide whether a programme changes regimen, audits supply, strengthens diagnostics, or invests in adherence support.
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