TY - JOUR
T1 - Specific and nonspecific responses to Plasmodium falciparum blood-stage parasites and observations on the gametocytemia in schoolchildren living in a malaria-endemic area of Mozambique
AU - Hogh, B
AU - Thompson, R
AU - Hetzel, C
AU - Fleck, S L
AU - Kruse, N A
AU - Jones, I
AU - Dgedge, M
AU - Barreto, J
AU - Sinden, R E
PY - 1995/1
Y1 - 1995/1
N2 - We have observed specific and nonspecific reactivities to the asexual states and gametocytes of Plasmodium falciparum and examined the effect of chloroquine and Fansidar (pyrimethamine/sulfadoxine) on the dynamics of gametocytemia. Schoolchildren peripheral blood films positive for P. falciparum gametocytes were identified in a malaria-endemic area of Mozambique. The children were randomly allocated into two groups to receive chloroquine or pyrimethamine/sulfadoxine, and were followed for 28 days after treatment. In patients harboring drug-sensitive parasites, asexual parasitemias were cleared by day 4, but gametocytes persisted for an additional 17 days. The prevalence of the asexual parasites was 67.6% in the chloroquine-treated group at day 0 and 61.1% at day 28, whereas in the pyrimethamine/sulfadoxine treated group, the initial parasite prevalence of 70.7% was reduced to 2.4% at day 28, suggesting a high prevalence of chloroquine-resistant parasites. On day 0, gametocyte prevalence was 59.5% in the chloroquine-treated group and in 68.3% in the pyrimethamine/sulfadoxine-treated group; these values were reduced to 5.6% and 2.4%, respectively, at day 28. Our results suggest strongly that there is no induction of gametocytogenesis by either course of chemotherapy.
AB - We have observed specific and nonspecific reactivities to the asexual states and gametocytes of Plasmodium falciparum and examined the effect of chloroquine and Fansidar (pyrimethamine/sulfadoxine) on the dynamics of gametocytemia. Schoolchildren peripheral blood films positive for P. falciparum gametocytes were identified in a malaria-endemic area of Mozambique. The children were randomly allocated into two groups to receive chloroquine or pyrimethamine/sulfadoxine, and were followed for 28 days after treatment. In patients harboring drug-sensitive parasites, asexual parasitemias were cleared by day 4, but gametocytes persisted for an additional 17 days. The prevalence of the asexual parasites was 67.6% in the chloroquine-treated group at day 0 and 61.1% at day 28, whereas in the pyrimethamine/sulfadoxine treated group, the initial parasite prevalence of 70.7% was reduced to 2.4% at day 28, suggesting a high prevalence of chloroquine-resistant parasites. On day 0, gametocyte prevalence was 59.5% in the chloroquine-treated group and in 68.3% in the pyrimethamine/sulfadoxine-treated group; these values were reduced to 5.6% and 2.4%, respectively, at day 28. Our results suggest strongly that there is no induction of gametocytogenesis by either course of chemotherapy.
KW - Adolescent
KW - Animals
KW - Antibodies, Protozoan/blood
KW - Antigens, Protozoan/immunology
KW - Antimalarials/pharmacology
KW - Blotting, Western
KW - C-Reactive Protein/analysis
KW - Child
KW - Chloroquine/pharmacology
KW - Computer Simulation
KW - Drug Combinations
KW - Drug Resistance
KW - Enzyme-Linked Immunosorbent Assay
KW - Fluorescent Antibody Technique
KW - Haptoglobins/analysis
KW - Humans
KW - Luminescent Measurements
KW - Malaria, Falciparum/drug therapy
KW - Models, Biological
KW - Mozambique/epidemiology
KW - Parasitemia/drug therapy
KW - Plasmodium falciparum/drug effects
KW - Prevalence
KW - Pyrimethamine/pharmacology
KW - Recombinant Proteins/immunology
KW - Sulfadoxine/pharmacology
M3 - Journal article
C2 - 7856825
SN - 0002-9637
VL - 52
SP - 50
EP - 59
JO - Journal. National Malaria Society
JF - Journal. National Malaria Society
IS - 1
ER -
