Plasmodium Falciparum Artemisinin Resistance Vietnam

Inclusion Criteria: * Age: from 6 months of age; * Fever (body temperature above 37.5C) or history of fever in the previous 24 hours; * Mono-infection with P.falciparum with parasite density between 500-100,000/µl * Written informed consent to participate to the trial. For patients aged less than 18 years, an informed consent will be obtained from a parent or a guardian. Exclusion Criteria: * Mixed malaria infection; * Pregnancy or lactation (urine test for β human chorionic gonadotropin to be performed on any woman of child bearing age unless menstruating); * Concomitant acute illness necessitating specific treatment (antibiotics); * Underlying chronic severe illness (e.g. cardiac, renal, hepatic diseases, HIV/AIDS). * Severe malnutrition; * Danger signs: * not able to drink * incontrollable vomiting * recent history of convulsions (\>1 in 24 hours) * unconscious state; neurological impairment * unable to sit or stand * Signs of severe malaria: 1. Cerebral malaria (unrousable coma) 2. Severe anaemia (Htc\< 15%) 3. Renal failure (serum creatinine \> 3 mg/dL) 4. Pulmonary oedema; 5. Hypoglycemia (\<40mg/dL) 6. Shock (systolic BP \< 70 mmHg in adults, 50 in children) 7. Spontaneous bleeding 8. Repeat generalized convulsions 9. Macroscopic haemoglobinuria 10. Severe jaundice * Persons who have received quinine, artemisinin or artemisinin derivatives within the last 7 days, 4-aminoquinolines within the last 14 days, pyrimethamine and/or sulfonamides within the last 28 days, or mefloquine within the last 56 days should be excluded from the in vitro testing