Monthly antimalarial chemotherapy to children in a holoendemic area of Liberia

IgG against Plasmodium falciparum variant surface antigens and growth inhibitory antibodies in Mozambican children receiving intermittent preventive treatment with sulfadoxine-pyrimethamine

“…This has been the case for the use of extended chemoprophylaxis in various settings (Bjorkman et al 1986;Bradley-Moore et al 1985;Geerligs et al 2003;Greenwood et al 1995;Hogh et al 1994;Laing 1984;Menendez et al 1997;Pringle and Avery-Jones 1966), where a significant reduction of malaria antibody responses was observed after termination of prophylaxis. Neither anti-VSA nor growth-inhibitory antibodies were measured in such studies.…”

Haemoglobin and haematocrit: is the threefold conversion valid for assessing anaemia in malaria-endemic settings?

“…Bland & Altman [12] argue that two methods designed to measure the same thing will inevitably give a positive linear regression, and the most useful comparison is gained by plotting the difference between the measures against the mean of the two measures. This method was used to compare haemoglobin (g/dl) and haematocrit (%) divided by a factor of three [20] to be able to compare the measurements on approximately the same scale ("grams of haemoglobin per dl").…”

Unexpected selections of Plasmodium falciparum polymorphisms in previously treatment-naïve areas after monthly presumptive administration of three different anti-malarial drugs in Liberia 1976–78

“…The temperature is generally between 21 and 32 °C. Malaria was holoendemic when the clinical study was conducted [29, 30]. In 1976 (prior to deployment of monthly presumptive treatment) the overall parasite prevalence in the study area assessed by blood slide microscopy in 2–9 years old children was 82% for P. falciparum , 39% for Plasmodium malariae and 9% for Plasmodium ovale [32].…”

“…A large field study conducted between 1976 and 1978 in four villages in northern Liberia where virtually no anti-malarials had been previously used was therefore revisited [29]. Children aged 2–9 years received monthly administrations of CQ, PYR, CPGN or placebo depending upon which village they lived in.…”

“…One drug was consistently used in each village. During the study period P. falciparum developed in vivo resistance to PYR and partially reduced susceptibility to CPGN whilst CQ remained effective [29–31]. The in vivo drug susceptibilities were assessed as Day 7 clearance of parasitaemia by microscopy after single doses of 10 mg/kg CQ, 2 mg/kg PYR or 1.5 mg/kg CPGN respectively.…”