Dataset Information

Plasmodium falciparum clearance rates in response to artesunate in Malian children with malaria: effect of acquired immunity.

ABSTRACT:

Background

Artemisinin resistance, a long parasite clearance half-life in response to artemisinin, has been described in patients with Plasmodium falciparum malaria in southeast Asia. Few baseline half-lives have been reported from Africa, where artemisinins were recently introduced.

Methods

We treated P. falciparum malaria in 215 Malian children aged 0.5-15 years with artesunate (0, 24, 48 hours) and amodiaquine (72, 96, 120 hours). We estimated half-life by measuring parasite density every 6 hours until undetectable and evaluated the effects of age, sex, ethnicity, and red blood cell (RBC) polymorphisms on half-life. We quantified the proportion of parasitized RBCs recognized by autologous immunoglobulin G (IgG).

Results

The geometric mean half-life was 1.9 hours (95% confidence interval, 1.8-2.0) and did not correlate with parasite ex vivo susceptibility to artemisinins. In a linear model accounting for host factors, half-life decreased by 4.1 minutes for every 1-year increase in age. The proportion of parasitized RBCs recognized by IgG correlated inversely with half-life (r = -0.475; P = .0006).

Conclusions

Parasite clearance in response to artesunate is faster in Mali than in southeast Asia. IgG responses to parasitized RBCs shorten half-life and may influence this parameter in areas where age is not an adequate surrogate of immunity and correlates of parasite-clearing immunity have not been identified.

Clinical trials registration

NCT00669084.

SUBMITTER: Lopera-Mesa TM

PROVIDER: S-EPMC3636783 | biostudies-literature | 2013 Jun

REPOSITORIES: biostudies-literature

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Publications

Plasmodium falciparum clearance rates in response to artesunate in Malian children with malaria: effect of acquired immunity.

Lopera-Mesa Tatiana M TM Doumbia Saibou S Chiang Serena S Zeituni Amir E AE Konate Drissa S DS Doumbouya Mory M Keita Abdoul S AS Stepniewska Kasia K Traore Karim K Diakite Seidina A S SA Ndiaye Daouda D Sa Juliana M JM Anderson Jennifer M JM Fay Michael P MP Long Carole A CA Diakite Mahamadou M Fairhurst Rick M RM

The Journal of infectious diseases 20130228 11

<h4>Background</h4>Artemisinin resistance, a long parasite clearance half-life in response to artemisinin, has been described in patients with Plasmodium falciparum malaria in southeast Asia. Few baseline half-lives have been reported from Africa, where artemisinins were recently introduced.<h4>Methods</h4>We treated P. falciparum malaria in 215 Malian children aged 0.5-15 years with artesunate (0, 24, 48 hours) and amodiaquine (72, 96, 120 hours). We estimated half-life by measuring parasite de ...[more]

PMID: 23448727

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Dataset Information

Plasmodium falciparum clearance rates in response to artesunate in Malian children with malaria: effect of acquired immunity.

Background

Methods

Results

Conclusions

Clinical trials registration

Publications

Plasmodium falciparum clearance rates in response to artesunate in Malian children with malaria: effect of acquired immunity.

Similar Datasets

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