The effects of malaria chemoprophylaxis given by traditional birth attendants on the course and outcome of pregnancy. Malaria chemosuppression in pregnancy. I. The effect of chemosuppressive drugs on maternal parasitaemia. Randomised placebo-controlled trial of iron supplementation and malaria chemoprophylaxis for prevention of severe anaemia and malaria in Tanzanian infants. Comparison of intermittent preventive treatment with chemoprophylaxis for the prevention of malaria during pregnancy in Mali. Assessment of the effect of the oral iron chelator deferiprone on asymptomatic Plasmodium falciparum parasitemia in humans. Malaria chemoprophylaxis, infection of the placenta and birth weight in Gambian primigravidae. Iron chelation as a chemotherapeutic strategy for falciparum malaria. The effect of oral iron therapy during treatment for Plasmodium falciparum malaria with sulphadoxine-pyrimethamine on Malawian children under 5 years of age. Tolerability of malaria chemoprophylaxis in non-immune travellers to sub-Saharan Africa: multicentre, randomised, double blind, four arm study.
A trial of malaria chemoprophylaxis given by traditional birth attendants was undertaken in a rural area of The Gambia where access to antenatal clinics is difficult. Women received one or more doses of Maloprim or placebo from a traditional birth attendant during 1049 of 1208 pregnancies (87%) recorded in 16 villages over a 3-year period. Primigravidae who received Maloprim had a lower parasite rate and a significantly higher mean packed cell volume than primigravidae who received placebo, and their babies were significantly heavier (6% low birth weight vs 22%). In multigravidae chemoprophylaxis reduced malaria parasitaemia but it had no beneficial effect on haemoglobin level and much less effect on birth weight than was observed in primigravidae. However, the mean birth weight of babies born to grandemultigravidae who received chemoprophylaxis was significantly higher than that of babies born to grandemultigravidae who did not. A randomized prophylactic drug trial was conducted in a malaria holoendemic area, in the Muheza District of Tanzania. Of 327 pregnant women, 124 received proguanil (PROG), 113 chloroquine (CQ), 90 the proguanil and chloroquine combination (CQ+PROG). Prophylaxis was supervised. Chemosuppressive efficacy was measured through the incidence of malaria breakthrough parasitaemias and clinical episodes. Groups were comparable by age, parity, residential area, and enrollment gestational age. Compliance and drug bio-availability was good. The median breakthrough time of the first parasitaemia episode for primigravidae (PG) and multigravidae (MG) was significantly shorter for the CQ group (PG = 56, MG = 78 days) than in the PROG (PG = 97, MG = 112 days) and the CQ+PROG (PG = 138, MG = 140 days) groups. 56% of the CQ group experienced 2 or more clinical episodes compared to 19% (PROG) and 10% (CQ+PROG). PROG and CQ+PROG did not differ significantly. Parasite densities and in vitro tests suggested that CQ selected for more and highly resistant strain(s). Proguanil is suitable for prophylaxis. However, proguanil resistance should be monitored as well as controlled drug distribution and usage. Malaria control strategies other than chemoprophylaxis should be investigated. Malaria and anaemia, especially that due to iron deficiency, are two leading causes of morbidity worldwide. Little is known about the relative contribution of Plasmodium falciparum infection and iron deficiency to the aetiology of anaemia in malaria-endemic areas. We undertook a randomised comparison of different strategies for control of anaemia and malaria in infants, including an assessment of the effect of iron supplementation on malaria susceptibility.
                832 infants born at one hospital in a malaria-hyperendemic area of Tanzania between January and October, 1995, were randomly assigned to group DI, receiving daily oral iron (2 mg/kg daily) plus weekly Deltaprim (3.125 mg pyrimethamine plus 25 mg dapsone); group IP, receiving iron plus weekly placebo; group DP, receiving daily placebo plus weekly Deltaprim; or group PP. supplementation was given from 8 to 24 weeks of age, and the weekly chemoprophylaxis from 8 to 48 weeks. The frequency of severe anaemia (packed-cell volume < 25%) and malaria episodes was assessed through a combination of passive case detection and cross-sectional surveys.
                The groups that received iron supplementation had a lower frequency of severe anaemia than those that did not receive iron (0.62 vs 0.87 cases per person-year; protective efficacy 28.8% [95% CI 6.3-45.8). Iron supplementation had no effect on the frequency of malaria (0.87 vs 1.00 cases per person-year; protective efficacy 12.8% [-12.8 to 32.5]). The groups that received malaria prophylaxis had lower frequencies of both severe anaemia (0.45 vs 1.04 episodes per person-year; protective efficacy 57.3% [43.0-67.9]) and malaria (0.53 vs 1.34 episodes per person-year; protective efficacy 60.5% [48.2-69.9]) than the groups that did not receive prophylaxis. After the end of the intervention period, children who had received malaria chemoprophylaxis had higher rates of severe anaemia and malaria than non-chemoprophylaxis groups (relative risks 2.2 [1.3-3.7] and 1.8 [1.3-2.6]).
                Malaria chemoprophylaxis during the first year of life was effective in prevention of malaria and anaemia but apparently impaired the development of natural immunity. Iron supplementation was effective in preventing severe anaemia without increasing susceptibility to malaria. Our findings support iron supplementation of infants to prevent iron-deficiency anaemia, even in malaria-endemic areas. Malaria during pregnancy contributes to maternal anemia and low birth weight. In East Africa, several studies have demonstrated that intermittent preventive treatment (IPT) with sulfadoxine-pyrimethamine (SP) is more efficacious than weekly chloroquine (CQ) chemoprophylaxis in preventing these adverse consequences. To our knowledge, there are no published trials evaluating IPT in West Africa.
                We undertook a randomized controlled trial of weekly CQ chemoprophylaxis, 2-dose IPT with CQ, and 2-dose IPT with SP; 1163 women were enrolled.
                In multivariate analyses, when compared with weekly CQ, IPT/SP was associated with a reduction in third-trimester anemia (adjusted odds ratio [AOR], 0.49; P<.001), placental parasitemia (AOR, 0.69; P=.04), and low birth weight (<2500 g) (AOR, 0.69; P=.04). The prevalence of placental infection remained unexpectedly high, even in the IPT/SP group (24.5%), possibly because of the intensity of seasonal transmission. There were no significant differences in stillbirths, spontaneous abortions, or neonatal deaths among the 3 groups.
                In Mali, IPT with SP appears more efficacious than weekly chloroquine chemoprophylaxis in preventing malaria during pregnancy. These data support World Health Organization recommendations to administer at least 2 doses of IPT during pregnancy. In intensely seasonal transmission settings in Mali, >2 doses may be required to prevent placental reinfection prior to delivery. While the parenteral iron-chelating agent desferrioxamine B has anti-malarial activity in humans, the usefulness of an orally active chelator for this indication has not been investigated previously in vivo. We conducted a prospective, double-blind, placebo-controlled, cross-over trial of deferiprone (L1; CP20; 1,2-dimethyl-3-hydroxypyridin-4-one) in 25 adult Zambians with asymptomatic Plasmodium falciparum parasitemia. Deferiprone was administered daily for three or four days in divided doses of 75 or 100 mg/kg of body weight, dosages that are effective for treating iron overload. No reduction in asexual intra-erythrocytic parasites was observed during or after deferiprone treatment. The mean peak plasma concentration of deferiprone (108.9 +/- 24.9 micromol/L) achieved was within the range demonstrated to inhibit the growth of P. falciparum in vitro, but the systemic exposure as determined by the 24-hr plasma concentration-time curve would not be predicted inhibit growth in vivo. No evidence of deferiprone-associated hematological toxicity was noted in this short-term study of these subjects, all of whom had clinical evidence of normal body iron stores. Because of the risk of neutropenia and other adverse effects with higher doses or prolonged use of the chelator, additional trials of deferiprone as a sole anti-malarial agent would not seem to be justified. In contrast, further efforts are needed to develop other orally active iron-chelating agents specifically for their anti-malarial action. A randomized, double blind, placebo-controlled community based trial of Maloprim (pyrimethamine 12.5 mg+dapsone 100 mg) administered to primigravid pregnant women by Traditional Birth Attendants was carried out in a rural area of The Gambia, West Africa. Placental histology showed less malaria infection in women who received chemoprophylaxis than in those who received placebo. The birth weight of children born to women who received chemoprophylaxis was increased by an average of 153 g. Within the treatment groups, there were no significant differences in the birthweights of babies born to women who had histological evidence of malaria infection of the placenta compared to those who had no malaria infection. This study confirms the beneficial effect of malaria prophylaxis for primigravid pregnant women but questions the mechanism by which malaria affects foetal development. To examine the effect of iron chelation against human malaria, 37 Zambians with asymptomatic Plasmodium falciparum infections were randomly assigned to 72-hr infusions of desferrioxamine B or placebo. Mean concentrations of ring forms decreased significantly with desferrioxamine B (P < 0.001) but not with a placebo. Over seven days of observation, mean parasite concentrations remained at the initial levels in six individuals originally given placebo, but decreased promptly with administration of desferrioxamine B (P = 0.001). Mean parasitemia was significantly lower for up to four weeks in 16 subjects treated with desferrioxamine B when compared with the eight who had received placebo only (P = 0.027). We conclude that iron chelation has antiplasmodial activity and may offer a new therapeutic strategy for falciparum malaria. In sub-Saharan countries, although malaria and malaria-associated anaemia are major public health problems, the usefulness of supplementary iron treatment for children with malaria-associated anaemia is unknown. In a 6-week period during the 1995 rainy season, 222 Malawian children aged < 5 years, who sought treatment for malaria, had > or = 500 parasites/microliter blood and at least 5 g haemoglobin (HB)/dl blood and whose parents gave consent, were randomized into a prospective study comparing the efficacy of sulphadoxine- pyrimethamine only (SP), SP plus daily iron (SPD) and SP plus weekly iron (SPW) as treatment for malaria-associated anaemia. The patients had their HB concentrations measured on enrollment (day 0), just before antimalarial treatment, and on days 3, 7, 14, 21 and 28; 215 (96.8%) completed the 28-day study. Among the children with 5-8 g HB/dl on enrolment, HB gain by the end of the study was significantly greater than in the children with > 8 g HB/dl initially (4.1 v. 2.2 g/dl; P < 0.05), and those in the SPD group gained significantly more HB by days 21 and 28 (3.6 and 4.9 g/dl, respectively) than those in either the SPW (2.7 and 3.7 g/dl, respectively) or the S2 groups (2.6 and 3.5 g/dl, respectively); there was no difference in HB gain between the SP and SPW groups. Type of treatment had no apparent effect, at any time during the study, on HB gains in those patients who had > 8 g HB/dl on enrolment. Thus the children with 5-8 g HB/dl on enrolment benefited from daily iron therapy whereas those with > 8 g HB/dl derived no significant benefit; improvement in HB depended most on whether enrolment HB was < or = 8.0 g/dl. As treatment with an effective antimalarial drug resulted in HB gains, irrespective of treatment group or HB concentration at enrolment, the anaemia observed may be mostly related to malaria. However, as a larger proportion of the iron-treated patients failed to clear their parasitaemias than of those given SP alone, oral iron may inhibit SP action. It is therefore recommended that, for children with both malaria and malaria-associated anaemia, the malaria should first be cleared with an effective antimalarial drug, such as SP, before the anaemia, if it still persists, is treated with iron. To compare the tolerability of malaria chemoprophylaxis regimens in non-immune travellers.
                Randomised, double blind, study with placebo run-in phase.
                Travel clinics in Switzerland, Germany, and Israel.
                Proportion of participants in each treatment arm with subjectively moderate or severe adverse events.
                623 non-immune travellers to sub-Saharan Africa: 153 each received either doxycycline, mefloquine, or the fixed combination chloroquine and proguanil, and 164 received the fixed combination atovaquone and proguanil.
                A high proportion of patients reported adverse events, even in the initial placebo group. No events were serious. The chloroquine and proguanil arm had the highest proportion of mild to moderate adverse events (69/153; 45%, 95% confidence interval 37% to 53%), followed by mefloquine (64/153; 42%, 34% to 50%), doxycycline (51/153; 33%, 26% to 41%), and atovaquone and proguanil (53/164; 32%, 25% to 40%) (P = 0.048 for all). The mefloquine and combined chloroquine and proguanil arms had the highest proportion of more severe events (n = 19; 12%, 7% to 18% and n = 16; 11%, 6% to 15%, respectively), whereas the combined atovaquone and proguanil and doxycycline arms had the lowest (n = 11; 7%, 2% to 11% and n = 9; 6%, 2% to 10%, respectively: P = 0.137 for all). The mefloquine arm had the highest proportion of moderate to severe neuropsychological adverse events, particularly in women (n = 56; 37%, 29% to 44% versus chloroquine and proguanil, n = 46; 30%, 23% to 37%; doxycycline, n = 36; 24%, 17% to 30%; and atovaquone and proguanil, n = 32; 20%, 13% to 26%: P = 0.003 for all). The highest proportion of moderate or severe skin problems were reported in the chloroquine and proguanil arm (n = 12; 8%, 4% to 13% versus doxycycline, n = 5; 3%, 1% to 6%; atovaquone and proguanil, n = 4; 2%, 0% to 5%; mefloquine, n = 2; 1%, 0% to 3%: P = 0.013).
                Combined atovaquone and proguanil and doxycyline are well tolerated antimalarial drugs. Broader experience with both agents is needed to accumulate reports of rare adverse events.
It is beneficial to give routine malaria chemoprophylaxis in sickle cell disease in areas where malaria is endemic.