In vivo parasitological measures of artemisinin susceptibility

Kasia Stepniewska, Elizabeth Ashley, Sue J Lee, Nicholas Anstey, Karen I Barnes, Tran Quang Binh, Umberto D'Alessandro, Nicholas Day, Peter De Vries, Grant Dorsey, Jean-Paul Guthmann, Mayfong Mayxay, Paul N Newton, Piero Olliaro, Lyda Osorio, Ric Price, Mark Rowland, Frank Smithuis, Walter R J Taylor, François NostenNicholas J White

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    Parasite clearance data from 18,699 patients with falciparum malaria treated with an artemisinin derivative in areas of low (n = 14,539), moderate (n = 2077), and high (n = 2083) levels of malaria transmission across the world were analyzed to determine the factors that affect clearance rates and identify a simple in vivo screening measure for artemisinin resistance. The main factor affecting parasite clearance time was parasite density on admission. Clearance rates were faster in high-transmission settings and with more effective partner drugs in artemisinin-based combination treatments (ACTs). The result of the malaria blood smear on day 3 (72 h) was a good predictor of subsequent treatment failure and provides a simple screening measure for artemisinin resistance. Artemisinin resistance is highly unlikely if the proportion of patients with parasite densities of <100,000 parasites//?L given the currently recommended 3-day ACT who have a positive smear result on day 3 is <3%; that is, for n patients the observed number with a positive smear result on day 3 does not exceed (n + 60)/24. � 2010 by the Infectious Diseases Society of America. All rights reserved.
    Original languageEnglish
    Pages (from-to)570-579
    Number of pages10
    JournalJournal of Infectious Diseases
    Publication statusPublished - 2010


    Cite this

    Stepniewska, K., Ashley, E., Lee, S. J., Anstey, N., Barnes, K. I., Binh, T. Q., ... White, N. J. (2010). In vivo parasitological measures of artemisinin susceptibility. Journal of Infectious Diseases, 201, 570-579.