title: Assessing parasite clearance during uncomplicatedPlasmodium falciparuminfection treated with artesunate monotherapy in Suriname.
abstract: BACKGROUND
  Artemisinin resistance inPlasmodium falciparumis suspected when the day 3 parasitemia is >10% when treated with artemisinin-based combination therapy or if >10% of patients treated with artemisinin-based combination therapy or artesunate monotherapy harbored parasites with half-lives ≥5 hours. Hence, a single-arm prospective efficacy trial was conducted in Suriname for uncomplicatedP. falciparuminfection treated with artesunate-based monotherapy for 3 days assessing day 3 parasitemia, treatment outcome after 28 days, and parasite half-life.
  
  
  METHODS
  The study was conducted in Paramaribo, the capital of Suriname, from July 2013 until July 2014. Patients with uncomplicatedPlasmodium falciparuminfection were included and received artesunate mono-therapy for three days. Day 3 parasitaemia, treatment outcome after 28 days and parasite half-life were determined. The latter was assessed with the parasite clearance estimator from the WorldWide Antimalarial Resistance Network (WWARN).
  
  
  RESULTS
  Thirty-nine patients were included from July 2013 until July 2014. The day 3 parasitemia was 10%. Eight patients (20.5%) could be followed up until day 28 and showed adequate clinical and parasitological response. Parasite half-life could only be determined from ten data series (25.7%). The median parasite half-life was 5.16 hours, and seven of these data series had a half-life ≥5 hours, still comprising 17.9% of the total data series.
  
  
  CONCLUSIONS
  The low follow-up rate and the limited analyzable data series preclude clear conclusions about the efficacy of artesunate monotherapy in Suriname and the parasite half-life, respectively. The emergence of at least 17.9% of data series with a parasite half-life ≥5 hours supports the possible presence of artemisinin resistance.
authors.affiliation: Foundation for Scientific Research Suriname (SWOS).
authors.forename: Stephen Gs
authors.initials: SG
authors.lastname: Vreden
authors.affiliation: Department of Internal Medicine, Academic Hospital Paramaribo.
authors.forename: Rakesh D
authors.initials: RD
authors.lastname: Bansie
authors.affiliation: Department of Public Health, Ministry of Health.
authors.forename: Jeetendra K
authors.initials: JK
authors.lastname: Jitan
authors.affiliation: Department of Biochemistry, Anton de Kom University of Suriname, Paramaribo, Suriname.
authors.forename: Malti R
authors.initials: MR
authors.lastname: Adhin
keywords: falciparum; malaria; parasite half-life; resistance