In vitro sensitivity of southern African reference isolates of Plasmodium falciparum to chloroquine and pyrimethamine.

The in vitro sensitivity to chloroquine and pyrimethamine of 19 culture-adapted southern African reference isolates of Plasmodium falciparum was determined using a 48-hour assay. Four isolates collected in KwaZulu, Natal, were sensitive to chloroquine, and one of these was sensitive to the drug in vivo. Eight isolates from KwaZulu or Mozambique were resistant to chloroquine in vitro. Six of these isolates were chloroquine-resistant in varying degrees in vivo. Four of five isolates from north-eastern Transvaal and two clinically chloroquine-resistant Malawian isolates were resistant to chloroquine in vitro. A wide range of pyrimethamine susceptibilities was detected (0.01 mumol/l to greater than 3.0 mumol/l), although most isolates were inhibited at 0.1 mumol/l, indicating a low level of resistance. These results confirm the presence of both chloroquine and pyrimethamine resistance in the endemic areas of South Africa. This has serious implications for the prophylaxis and treatment of P. falciparum malaria in South Africa.

[1]  M. Markus,et al.  Enzyme typing of southern African isolates of Plasmodium falciparum by polyacrylamide gel electrophoresis. , 1990, Transactions of the Royal Society of Tropical Medicine and Hygiene.

[2]  J. Golenser,et al.  Typing of southern African isolates of Plasmodium falciparum using monoclonal antibodies. , 1990, The American journal of tropical medicine and hygiene.

[3]  B. Sharp,et al.  In vitro confirmation of chloroquine-resistant Plasmodium falciparum malaria in KwaZulu. , 1988, South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde.

[4]  B. Sharp,et al.  In vitro cultivation of southern African strains of Plasmodium falciparum and gametocytogenesis. , 1988, South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde.

[5]  M. Raviglione APPEARANCE OF CHLOROQUINE-RESISTANT FALCIPARUM MALARIA IN SWAZILAND , 1987, The Lancet.

[6]  P. Nguyen-Dinh,et al.  Evaluation of sporontocidal compounds using Plasmodium falciparum gametocytes produced in vitro. , 1985, The American journal of tropical medicine and hygiene.

[7]  C. Olweny,et al.  Chloroquine resistant Plasmodium falciparum malaria in Zimbabwe. , 1984, British medical journal.

[8]  F. H. Spracklen,et al.  Malaria 1984. Part II. Drug-resistant malaria. , 1984, South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde.

[9]  J. Jensen,et al.  Clinical drug-resistant falciparum malaria acquired from cultured parasites. , 1981, The American journal of tropical medicine and hygiene.

[10]  B. Kean Chloroquine-resistant falciparum malaria from Africa. , 1979, JAMA.

[11]  W. Trager,et al.  Plasmodium falciparum in culture: establishment of additional strains. , 1978, The American journal of tropical medicine and hygiene.

[12]  W. Trager,et al.  Chloroquine resistance produced in vitro in an African strain of human malaria. , 1978, Science.

[13]  W. Trager,et al.  Plasmodium falciparum in culture: use of outdated erthrocytes and description of the candle jar method. , 1977, The Journal of parasitology.

[14]  C. F. Hansford Chloroquine resistance in Plasmodium falciparum in KwaZulu, 1983-1988. , 1989, South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde.

[15]  G. Beale,et al.  Variability in drug susceptibility amongst clones and isolates of Plasmodium falciparum. , 1988, Transactions of the Royal Society of Tropical Medicine and Hygiene.

[16]  B. Sharp,et al.  An analysis of 10 years of retrospective malaria data from the Kwa Zulu areas of Natal , 1988 .

[17]  D. Koech,et al.  Response of Plasmodium falciparum to dihydrofolate reductase inhibitors in Malindi, Kenya. , 1986, Transactions of the Royal Society of Tropical Medicine and Hygiene.

[18]  J. Herbst,et al.  In vitro chloroquine-resistant Plasmodium falciparum malaria in the Natal/Kwazulu area. , 1985, South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde.

[19]  W. Watkins,et al.  In vitro response of Kenyan Plasmodium falciparum to chloroquine in different media. , 1985, Transactions of the Royal Society of Tropical Medicine and Hygiene.

[20]  D. Bac,et al.  In vivo and in vitro chloroquine-resistant falciparum malaria in Venda , 1985 .

[21]  A. Schapira Concomitant resistance to pyrimethamine and cycloguanil of chloroquine-resistant falciparum malaria from East Africa: an in vitro study of 12 isolates. , 1984, Transactions of the Royal Society of Tropical Medicine and Hygiene.

[22]  E. Onori The problem of Plasmodium falciparum drug resistance in Africa south of the Sahara. , 1984, Bulletin of the World Health Organization.

[23]  G. Beale,et al.  Susceptibility of Plasmodium falciparum to five drugs: an in vitro study of isolates mainly from Thailand. , 1983, Transactions of the Royal Society of Tropical Medicine and Hygiene.

[24]  M. Smalley,et al.  In vitro demonstration of pyrimethamine resistance of "wild" Plasmodium falciparum in The Gambia. , 1982, Transactions of the Royal Society of Tropical Medicine and Hygiene.

[25]  B. Darlow,et al.  Comparison of in vitro pyrimethamine assays and in vivo response to sulphadoxine-pyrimethamine in Plasmodium falciparum from Papua New Guinea. , 1982, Transactions of the Royal Society of Tropical Medicine and Hygiene.

[26]  P. Nguyen-Dinh,et al.  Pyrimethamine sensitivity in Plasmodium falciparum: determination in vitro by a modified 48-hour test. , 1980, Bulletin of the World Health Organization.

[27]  P. Effersøe,et al.  Chloroquine-resistant Plasmodium falciparum malaria in Kenya. , 1979, Transactions of the Royal Society of Tropical Medicine and Hygiene.