A single lower dose of primaquine is as effective as the higher standard dose that is recommended for preventing transmission of the malarial parasite Plasmodium falciparum from humans to mosquitoes, report researchers from the London School of Hygiene and Tropical Medicine, in the United Kingdom (Eziefula AC et. Lancet Infect Dis. doi:10.1016/S1473-309970268-8 [published online November 12, 2013]).
Mature P falciparum gametocytes can persist in the bloodstream after artemisinin combination therapy (ACT). Because of this, primaquine, the only drug that can completely eradicate these gametocytes, has been recommended by the World Health Organization to be used in addition to ACT in many countries.
Friedrich MJ. Reduced Dose of Primaquine Effective in Blocking Malaria Transmission. JAMA. 2014;311(3):235. doi:10.1001/jama.2013.285742