HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Watkins, W. M. Articles by Koech, D. K. Search for Related Content PubMed PubMed Citation Articles by Watkins, W. M. Articles by Koech, D. K. Pubmed/NCBI databases Compound via MeSH Substance via MeSH Hazardous Substances DB RIBOFLAVIN

In Vitro Susceptibility of Plasmodium falciparum Isolates from Jilore, Kenya, to Antimalarial Drugs

William M. Watkins^*,,,, Robert E. Howells, A. David Brandling-Bennett^*,, AND David K. Koech^*

^* Biomedical Sciences Research Centre, Kenya Medical Research Institute, Nairobi, Kenya
Wellcome Trust Research Laboratories, Nairobi, Kenya
Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, England
U.S. Department of Health and Human Services, Centers for Disease Control, Division of Parasitic Diseases, Atlanta, Georgia

Twenty-six Plasmodium falciparum isolates obtained during a prophylaxis study at Jilore primary school, Malindi, Kenya, were adapted to in vitro culture and their susceptibility to 13 antimalarial drugs was tested by a modified radioisotopic method. Pyrimethamine, chloroquine, amodiaquine, cycloguanil, chlorcycloguanil, quinine, quinidine and sulfadoxine, and the experimental compounds MB 35769, mefloquine, WR 184806, parvoquone, and menoctone were used. The isolates could be divided into two groups with significantly different susceptibility to pyrimethamine, shown by a 755-fold difference in the mean ID₅₀ values (2.77 ± 1.98 x 10^-10 mol/l and 2.09 ± 1.64 x 10^-7 mol/l). The mean susceptibility of the two groups differed 7.7-fold for chlorcycloguanil and 14.6-fold for cycloguanil, but were not significantly different for the other drugs. All isolates were more sensitive to amodiaquine than to chloroquine in vitro. The ratio of the geometric mean ID₅₀ values of chloroquine to amodiaquine was 3.13. The ratio for the chemically related compounds parvoquone to menoctone was 5.63, quinine to quinidine was 5.58, and mefloquine to WR 184806 was 12.16.

Accepted for publication May 1, 1987.