Korean J Parasitol.  2015 Feb;53(1):35-41. 10.3347/kjp.2015.53.1.35.

Sensitivity of Plasmodium falciparum to Antimalarial Drugs in Hainan Island, China

• Wang SQ
• Wang GZ
• Li YC
• Meng F
• Lin SG
• Zhu ZH
• Sun DW
• He CH
• Hu XM
• Du JW

• KMID: 2381794
• DOI: http://doi.org/10.3347/kjp.2015.53.1.35

Abstract

Pyronaridine and artesunate have been shown to be effective in falciparum malaria treatment. However, pyronaridine is rarely used in Hainan Island clinically, and artesunate is not widely used as a therapeutic agent. Instead, conventional antimalarial drugs, chloroquine and piperaquine, are used, explaining the emergence of chloroquine-resistant Plasmodium falciparum. In this article, we investigated the sensitivity of P. falciparum to antimalarial drugs used in Hainan Island for rational drug therapy. We performed in vivo (28 days) and in vitro tests to determine the sensitivity of P. falciparum to antimalarial drugs. Total 46 patients with falciparum malaria were treated with dihydroartemisinin/piperaquine phosphate (DUO-COTECXIN) and followed up for 28 day. The cure rate was 97.8%. The mean fever clearance time (22.5+/-10.6 hr) and the mean parasite clearance time (27.3+/-12.2 hr) showed no statistical significance with different genders, ages, temperatures, or parasite density (P>0.05). The resistance rates of chloroquine, piperaquine, pyronarididine, and artesunate detected in vitro were 71.9%, 40.6%, 12.5%, and 0%, respectively (P<0.0001). The resistance intensities decreased as follows: chloroquine>piperaquine>pyronarididine>artesunate. The inhibitory dose 50 (IC50) was 3.77x10(-6) mol/L, 2.09x10(-6) mol/L, 0.09x10(-6) mol/L, and 0.05x10(-6) mol/L, and the mean concentrations for complete inhibition (CIMC) of schizont formation were 5.60x10(-6) mol/L, 9.26x10(-6) mol/L, 0.55x10(-6) mol/L, and 0.07x10(-6) mol/L, respectively. Dihydroartemisinin showed a strong therapeutic effect against falciparum malaria with a low toxicity.

Keyword

Plasmodium falciparum; antimalarial; sensitivity; in vivo and in vitro test

MeSH Terms

Adolescent
Adult
Aged
Antimalarials/*pharmacology/*therapeutic use
Child
Child, Preschool
China
Female
Humans
Inhibitory Concentration 50
Malaria, Falciparum/*drug therapy/parasitology
Male
Middle Aged
Parasitic Sensitivity Tests
Plasmodium falciparum/*drug effects
Treatment Outcome
Young Adult
Antimalarials