Response of children with Plasmodium falciparum to chloroquine and development of a national malaria treatment policy in Zaire.

In vivo sensitivity of Plasmodium falciparum to chloroquine was evaluated in 4 of 9 regions of Zaire in 1985 to develop a national strategy for treatment of malaria. Children less than 5 years of age were treated with either a single dose of chloroquine base, 10 mg/kg, or a dose of 25 mg/kg given over 3 d. A modified 7-day World Health Organization in vivo test was used with follow-up 2, 3 and 7 d after the start of treatment. 339 children were studied. In Bwamanda 92% of children were aparasitaemic 7 days after chloroquine, 10 mg/kg, but in Kinshasa only 44% were free of parasites after 25 mg/kg chloroquine. The mean drop in parasite density among those who did not clear parasites by day 7 was greater than 98% of the initial value. Although the parasite density decreased markedly, the failure of most subjects to become aparasitaemic indicated a marked decrease in parasite sensitivity since 1983. Only one child of 51 who were initially febrile remained febrile, although 14 (28%) of these had resistant parasites. The decrease in parasitaemia and temperature, even among children with resistant strains, led the Ministry of Health to recommend 25 mg/kg chloroquine as first line treatment for fever/malaria in their national malaria control plan. The plan includes drug sensitivity surveillance and a referral system for patients who do not respond to chloroquine treatment.

Antimalarial activity of 20 crude extracts from nine African medicinal plants used in Kinshasa, Congo.

Twenty extracts including ten EtOH and ten CH2Cl2 from different parts of nine African medicinal plants used in Congolese traditional medicine for the treatment of malaria, were submitted to a pharmacological test in order to evaluate their effect on P. falciparum growth in vitro. Of these plant species, 14 (70%) extracts including EtOH and CH2Cl2 from Cassia occidentalis leaves, Cryptolepis sanguinolenta root bark, Euphorbia hirta whole plant, Garcinia kola stem bark and seeds, Morinda lucida leaves and Phyllanthus niruri whole plant produced more than 60% inhibition of the parasite growth in vitro at a test concentration of 6 microg/ml. Extracts from E. hirta, C. sanguinolenta and M. morindoides showed a significant chemosuppression of parasitaemia in mice infected with P. berghei berghei at orally given doses of 100-400 mg/kg per day.

[Malaria and pregnancy. Epidemiological situation in Kinshasa (Zaïre)]. / Paludisme et grossesse. Situation épidémiologique à Kinshasa (Zaïre).

By regular blood smears to 730 women (430 pregnant women and 250 non pregnant) authors state precisely epidemiologic situation of malaria to women at Kinshasa. The prevalence of malaria of pregnant women is 22 per cent against 6.1 per cent for non pregnant adult women. Malarial infestation in gravido-puerperal period is : mother : 23.7 per cent ; umbilical cord : 3.1 per cent ; newborn : 5.4 per cent ; placenta : 10.1 per cent. Plasmodium falciparum is the principal agent of malaria at Kinshasa. Neither age, nor parity constitute risk factors of malaria. Many cases of malaria without fever exist at Kinshasa. Newborn with malaria and from pregnancies with infected placentas present at the birth a small weight. Placentas of pregnancies with malaria and infected have invariably the same weight.

[Chemoresistance of Plasmodium falciparum in Kinshasha. In vivo tests and chloroquine absorption]. / Chimio-résistance de Plasmodium falciparum a Kinshasa. Tests in vivo et absorption de chloroquine.

With the test in vivo and the bleeding dosage of chloroquine, authors report the rate of resistance of chloroquine to Plasmodium falciparum. 2.3% of Plasmodium falciparum in Kinshasa are resistant to chloroquine.

In-vivo antimalarial activity of Cassia occidentalis, Morinda morindoides and Phyllanthus niruri.

The ethanolic, dichloromethane and lyophilized aqueous extracts of Cassia occidentalis root bark, Morinda morindoides leaves and whole plants of Phyllanthus niruri were evaluated for their antimalarial actvity in vivo, in 4-day, suppressive assays against Plasmodium berghei ANKA in mice. No toxic effect or mortality was observed in mice treated, orally, with any of the extracts as a single dose, of 500 mg/kg body weight, or as the same dose given twice weekly for 4 weeks (to give a total dose of 4 g/kg). No significant lesions were observed, by eye or during histopathological examinations, in the hearts, lungs, spleens, kidneys, livers, large intestines or brains of any mouse. At doses of 200 mg/kg, all the ethanolic and dichloromethane extracts produced significant chemosuppressions of parasitaemia (of > 60% for C. occidentalis root bark and Ph. niruri whole plant, and of 30% for M. morindoides leaves) when administered orally. The most active ethanolic extract, that of Ph. niruri, reduced parasitaemia by 73%. The dichloromethane extracts of M. morindoides and Ph. niruri produced similar reductions (74% and 72% chemosuppression, respectively), whereas that of C. occidentalis was slightly less active (60% chemosuppression). Each lyophilized aqueous extract was less active than the corresponding ethanolic extract.