H Yang1, D Liu, K Huang, C Zhang, C Li. 1. Institute of Malaria Prevention and Treatment of Yunnan Province, Simao 665000.
Abstract
AIM: To understand the changes in the sensitivity of Plasmodium falciparum to pyronaridine in the south of Yunnan Province. METHODS: WHO standard in vivo and in vitro microtest was used. RESULTS: In 1984-1985 and 1995, 36 and 39 cases of acute falciparum malaria were observed, the average defervescence time being 32.7 +/- 16.0 h and 56.2 +/- 27.4 h, the mean asexual parasite clearance time, 64.2 +/- 22.9 h and 55.3 +/- 11.8 h, and the recrudescence rate of patients followed up for 28 days, 15.2%(5/33) and 37.5%(9/24), respectively. The resistance rates of resistant isolates by in vitro microtest were 0(0/24), 8.8%(3/34), 13.8%(4/29) and 36.4%(4/11) in 1988, 1990, 1992 and 1995, respectively, while the corresponding ID50 were 13.0, 20.0, 32.0 and 40.0 nmol/L, ID95 were 48.0, 136.0, 325.0 and 330.0 nmol/L, the mean concentrations for complete inhibition of schizont formation were 32.6, 99.5, 148.2 and 190.1 nmol/L, respectively. CONCLUSION: The sensitivity of Plasmodium falciparum to pyronaridine was found to have a tendency of continuous dropping in south Yunnan.
AIM: To understand the changes in the sensitivity of Plasmodium falciparum to pyronaridine in the south of Yunnan Province. METHODS: WHO standard in vivo and in vitro microtest was used. RESULTS: In 1984-1985 and 1995, 36 and 39 cases of acute falciparum malaria were observed, the average defervescence time being 32.7 +/- 16.0 h and 56.2 +/- 27.4 h, the mean asexual parasite clearance time, 64.2 +/- 22.9 h and 55.3 +/- 11.8 h, and the recrudescence rate of patients followed up for 28 days, 15.2%(5/33) and 37.5%(9/24), respectively. The resistance rates of resistant isolates by in vitro microtest were 0(0/24), 8.8%(3/34), 13.8%(4/29) and 36.4%(4/11) in 1988, 1990, 1992 and 1995, respectively, while the corresponding ID50 were 13.0, 20.0, 32.0 and 40.0 nmol/L, ID95 were 48.0, 136.0, 325.0 and 330.0 nmol/L, the mean concentrations for complete inhibition of schizont formation were 32.6, 99.5, 148.2 and 190.1 nmol/L, respectively. CONCLUSION: The sensitivity of Plasmodium falciparum to pyronaridine was found to have a tendency of continuous dropping in south Yunnan.
Authors: Simon L Croft; Stephan Duparc; Sarah J Arbe-Barnes; J Carl Craft; Chang-Sik Shin; Lawrence Fleckenstein; Isabelle Borghini-Fuhrer; Han-Jong Rim Journal: Malar J Date: 2012-08-09 Impact factor: 2.979