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Purpose Cancer of the prostate (CaP) is the leading cancer among men in sub-Saharan Africa (SSA). A substantial proportion of these men with CaP are diagnosed at late (usually incurable) stages, yet little is known about the etiology of CaP in SSA. Methods We established the Men of African Descent and Carcinoma of the Prostate Network, which includes seven SSA centers partnering with five US centers to study the genetics and epidemiology of CaP in SSA. We developed common data elements and instruments, regulatory infrastructure, and biosample collection, processing, and shipping protocols. We tested this infrastructure by collecting epidemiologic, medical record, and genomic data from a total of 311 patients with CaP and 218 matched controls recruited at the seven SSA centers. We extracted genomic DNA from whole blood, buffy coat, or buccal swabs from 265 participants and shipped it to the Center for Inherited Disease Research (Baltimore, MD) and the Centre for Proteomics and Genomics Research (Cape Town, South Africa), where genotypes were generated using the UK Biobank Axiom Array. Results We used common instruments for data collection and entered data into the shared database. Double-entered data from pilot participants showed a 95% to 98% concordance rate, suggesting that data can be collected, entered, and stored with a high degree of accuracy. Genotypes were obtained from 95% of tested DNA samples (100% from blood-derived DNA samples) with high concordance across laboratories. Conclusion We provide approaches that can produce high-quality epidemiologic and genomic data in multicenter studies of cancer in SSA.

Summary The controlled induction of haemoxygenase-1 (HO-1), an enzyme that catabolizes haem, has been shown to reduce haem, preventing pathologies associated with haem toxicity. The hemoglobin genotype HbAS confers reduced susceptibility to severe complications of malaria by a mechanism that is not well understood. Using a longitudinal approach, we investigated the effect of baseline concentrations of HO-1 on the accumulation of haem during acute Plasmodium falciparum malaria in HbAS and HbAA genotypes. Plasma concentrations of haem, HO-1 and cytokines were quantified in venous blood obtained from children (9 months–5 years of age) during malaria infection, and at convalescence (baseline levels). Parasitaemia was determined during malaria infection. In patients with the HbAA genotype, there was a significant elevation in the plasma concentration of haem (P = 0.002), and a consequent increased induction of HO-1 (P

We conducted a genome-wide association study of host resistance to severePlasmodium falciparummalaria in over 17,000 individuals from 11 malaria-endemic countries, undertaking a wide ranging analysis which identifies five replicable associations with genome-wide levels of evidence. Our findings include a newly implicated variant on chromosome 6 associated with risk of cerebral malaria, and the discovery of an erythroid-specific transcription start site underlying the association inATP2B4. Previously reported HLA associations cannot be replicated in this dataset. We estimate substantial heritability of severe malaria (h2~ 23%), of which around 10% is explained by the currently identified associations. Our dataset will provide a major building block for future research on the genetic determinants of disease in these diverse human populations.

Many human genetic associations with resistance to malaria have been reported, but few have been reliably replicated. We collected data on 11,890 cases of severe malaria due to Plasmodium falciparum and 17,441 controls from 12 locations in Africa, Asia and Oceania. We tested 55 SNPs in 27 loci previously reported to associate with severe malaria. There was evidence of association at P < 1 × 10(-4) with the HBB, ABO, ATP2B4, G6PD and CD40LG loci, but previously reported associations at 22 other loci did not replicate in the multicenter analysis. The large sample size made it possible to identify authentic genetic effects that are heterogeneous across populations or phenotypes, with a striking example being the main African form of G6PD deficiency, which reduced the risk of cerebral malaria but increased the risk of severe malarial anemia. The finding that G6PD deficiency has opposing effects on different fatal complications of P. falciparum infection indicates that the evolutionary origins of this common human genetic disorder are more complex than previously supposed.

Killer-cell immunoglobulin-like receptors (KIRs) are a group of natural killer cell receptors (NKRs) that regulate NK-cell-mediated production of interferon gamma (IFN-γ) in response to infection. These receptors have recently been suggested to influence the severity of clinical Plasmodium falciparum malaria infection. We examined the KIR locus in relation to malaria in children from southwest Nigeria. Sequence specific priming (SSP)-PCR was used to detect the KIR genes. The presence or absence of fifteen different KIR genes was determined in each individual and the proportions compared across 3 clinical groups; asymptomatic malaria, uncomplicated clinical malaria and severe clinical malaria. The genes KIR2DL5, KIR2DS3 and KIR2DS5 were present in a significantly higher proportion of individuals in the asymptomatic control group than in the malaria cases. Furthermore, KIR2DS3 and KIR2DS5 were present in a higher proportion of uncomplicated malaria cases than severe malaria cases. Carriage c-AB2 genotype (which comprises all centromeric KIR genes including KIR2DL5, KIR2DS3 and KIR2DS5) decreases with severity of the disease suggesting that the KIR AB profile might be associated with protection from severe malaria infection in this population in Nigeria.

This study was conducted to determine the malariometric indices of children in three different settings in Ibadan, Nigeria. Children were recruited from an urban slum (Oloomi) and a periurban (Sasa) and a rural community (Igbanda) in Ibadan. Children aged between 2 and 10 years were randomly selected from primary schools in the urban and periurban areas. In the rural community, children were recruited from the centre of the village. A total of 670 (55.0%) out of 1218 children recruited were positive for malaria parasitaemia. The urban population had the highest proportion of children with malaria parasitaemia. Splenomegaly was present in 31.5%, hepatomegaly in 41.5%, hepatosplenomegaly in 27.5%, and anaemia in 25.2% of the children. The parasite density was not significantly different among children in the three communities. Children in the rural community had the highest mean PCV of 34.2% and the lowest rates of splenomegaly (6.1%), hepatomegaly (7.6%), and hepatosplenomegaly (4.6%). The spleen rates, liver rates, and presence of hepatosplenomegaly and anaemia were similar in the urban and periurban communities. The malariometric indices among the asymptomatic carriers were high, especially in the urban slum. This stresses the need for intensified efforts at controlling the disease in the study area.

Background Malnutrition in infants during weaning has been attributed to inappropriate complementary feeding practices and it underlies more than one-third of child mortality in Nigeria. Thus, addressing the influence of complementary feeding practice on nutritional status may be an important approach to reducing the burden of child malnutrition. This cross-sectional study investigated the association between complementary feeding practices among mothers and nutritional status of their infants in Akpabuyo Local Government Area, Nigeria. The study enrolled 330 mother–child pairs from 10 randomly selected out of 32 Health Facilities in Akpabuyo. Socio-demographic information, child and maternal characteristics were obtained using an interviewer-administered questionnaire. Complementary feeding practices were assessed with World Health Organization infant and young child feeding indicators. Nutritional indicators wasting, underweight and stunting were determined. Results Prevalence of timely introduction of complementary feeding among infants aged 6–8 months was 85.4%, minimum dietary diversity rate was 31.5%, and minimum meal frequency 36.7%, the rate of minimum acceptable diet was 7.3%. One-third (33.3%) of the infants were underweight, 26.4%, wasted and 24.6%, stunted. Children who did not receive timely complementary foods had higher odds for wasting (OR 5.15; 95% CI 1.50–17.73). Children who did not receive the minimum dietary diversity had higher odds for underweight than children who received the minimum dietary diversity (OR 2.07; 95% CI 1.17–3.70). Children who did not receive the minimum feeding frequency were more likely to be stunted than their peers who received the minimum feeding frequency (OR 1.57; 95% CI 1.53–4.03). Conclusion Sub-optimal complementary feeding predisposed to infant’s malnutrition.

Host genetic factors that influence the outcome of Plasmodium falciparum malaria infection are not fully understood. These include alpha-thalassemia, sickle cell disease, glucose-6-phosphate dehydrogenase (G6PD) deficiency and cytochrome b5 reductase 3 (CYB5R3) T117S and ferroportin Q248H polymorphisms. G6PD, an X-linked gene, encodes the sole enzyme in red blood cells that produces NADPH for protection from reactive oxygen species. Hemi- or homozygosity for G6PD A+ (G6PD c. 376G) is an African specific polymorphism with reduced activity (PMID:26633385) but no apparent phenotype; hemi- or homozygosity for G6PD A- (G6PD c 202A/376G) is associated with both decreased activity and increased risk for oxidant-induced hemolysis (PMID:27040960). A Malaria Genomic Epidemiology Network (MalariaGEN) study with almost 30,000 participants reported that G6PD A- increases the risk for severe malarial anemia (PMID:25261933). CYB5R3 in red blood cells transfers electrons from NADH to cytochrome b5, which in turn converts methemoglobin to hemoglobin. The African-specific CYB5R3 T117S variant, is not associated with methemoglobinemia (PMID:9048929) but may afford some protection from malarial anemia in Zambian children. A prevalent African-specific Q248H mutation of the iron exporter, ferroportin, may protect from high malarial parasitemia (PMID: 29599243). We genotyped 212 Nigerian children (age 4 months - 16 years) for these genetic factors: 117 were asymptomatic children who were studied in the community and 95 were children who were studied at the time of admission to hospital with severe malaria (severe anemia and/or cerebral malaria). We isolated DNA from dried blood spots and crude DNA lysate was used for Taqman genotyping to screen for G6PD A+, G6PD A-, FPN Q248H, sickle cell disease and CYB5R3 T117S and multiplex PCR was used to identify the 3.7 kb and 4.2 kb α-globin gene deletions. The clinical characteristics of the two groups of children are shown in Table 1. Children with severe malaria were significantly younger than the children from the community. The gene frequency of CYB5R3 T117S was 0.303, of hemoglobin S was 0.094, and of FPN Q248H was 0.062. The prevalences of hemizygous and homozygous G6PD A+ and A- were 13.9% and 16.0%, respectively. In addition, the prevalences of single and double alpha globin gene deletions were 34.7 % and 11.7%, respectively. Table 2 compares the prevalence of these genotypes in asymptomatic children versus those admitted with severe malaria. Alpha-thalassemia tended to be more prevalent in the asymptomatic children while ferroportin Q248H and G6PD A- were more prevalent in the children with severe malaria. Some genes seemed to have heterogenous associations: sickle trait and homozygous CYB5R3 T117S tended to be more prevalent in the asymptomatic children while hemoglobin SS and heterozygous T117S tended to be more prevalent in the children with severe malaria. In a logistic regression model that adjusted for age, alpha thalassemia (odds ratio 0.6, P=0.038), hemoglobin S trait (odds ratio 0.5, P=0.203), and CYB5R3 T117S homozygous state (odds ratio 0.5, P=0.211) independently decreased the risk of severe malaria, while ferroportin Q248H (odds ratio 5.1, P=0.008) and G6PD deficiency (1.6, P=0.049) independently increased the risk of severe malaria. In conclusion, our results suggest that common genetic factors affect the risk of severe malaria in children. Research to illuminate the mechanisms of these effects may enhance our understanding of the pathogenesis of severe malaria and point to novel preventive and therapeutic measures. Disclosures Gordeuk: Global Blood Therapeutics: Consultancy, Honoraria, Research Funding; Emmaus: Consultancy, Honoraria; Novartis: Consultancy, Honoraria, Research Funding; Modus Therapeutics: Consultancy, Honoraria; Pfizer: Research Funding; Inctye: Research Funding; CSL Behring: Consultancy, Honoraria, Research Funding; Ironwood: Research Funding; Imara: Research Funding.

Comment inK13-Propeller Mutations and Malaria Resistance, http://www.nejm.org/doi/full/10.1056/NEJMe1604520; International audience; BACKGROUND:Recent gains in reducing the global burden of malaria are threatened by the emergence of Plasmodium falciparum resistance to artemisinins. The discovery that mutations in portions of a P. falciparum gene encoding kelch (K13)-propeller domains are the major determinant of resistance has provided opportunities for monitoring such resistance on a global scale.METHODS:We analyzed the K13-propeller sequence polymorphism in 14,037 samples collected in 59 countries in which malaria is endemic. Most of the samples (84.5%) were obtained from patients who were treated at sentinel sites used for nationwide surveillance of antimalarial resistance. We evaluated the emergence and dissemination of mutations by haplotyping neighboring loci.RESULTS:We identified 108 nonsynonymous K13 mutations, which showed marked geographic disparity in their frequency and distribution. In Asia, 36.5% of the K13 mutations were distributed within two areas--one in Cambodia, Vietnam, and Laos and the other in western Thailand, Myanmar, and China--with no overlap. In Africa, we observed a broad array of rare nonsynonymous mutations that were not associated with delayed parasite clearance. The gene-edited Dd2 transgenic line with the A578S mutation, which expresses the most frequently observed African allele, was found to be susceptible to artemisinin in vitro on a ring-stage survival assay.CONCLUSIONS:No evidence of artemisinin resistance was found outside Southeast Asia and China, where resistance-associated K13 mutations were confined. The common African A578S allele was not associated with clinical or in vitro resistance to artemisinin, and many African mutations appear to be neutral. (Funded by Institut Pasteur Paris and others.).

As the genetic diversity of Plasmodium falciparum infections in humans is implicated in the pathogenesis of malaria, the association between P. falciparum diversity at the merozoite surface protein-2 (msp2) locus and the severity of childhood malaria was investigated in Ibadan, in south-western Nigeria. The 400 children enrolled had acute uncomplicated malaria (144), cerebral malaria (64), severe malarial anaemia (67) or asymptomatic infections with P. falciparum (125). Nested PCR was used to investigate the msp2 genotype(s) of the parasites infecting each child. In terms of the complexity of infection and frequency of polyinfection, the children with asymptomatic infection were significantly different from those with uncomplicated malaria or severe malaria. The median number of FC27 alleles detected was higher in the asymptomatic children than in the symptomatic. After controlling for age and level of parasitaemia (with 'asymptomatic infection' as the reference category), a child in whom no FC27 alleles were detected was found to be at five-fold greater risk of uncomplicated malaria, and a child without polyinfection was found to have a three-fold increased risk of severe malarial anaemia and a six-fold increased risk of cerebral malaria. It therefore appears that msp2 genotypes are associated with asymptomatic carriage and that children with mono-infections are more likely to develop severe malaria than children with polyinfection.

Background Men of African descent have the highest incidence and mortality rates of prostate cancer (PrCa) worldwide. Notably, PrCa is increasing in Africa with Nigerian men being mostly affected. Thus, it is important to understand risk factors for PrCa in Nigeria and build capacity for cancer research. The goals of this study were to determine the feasibility of conducting an epidemiological study of PrCa and to obtain preliminary data on risk factors for PrCa in Nigeria. Methods A case–control study (50 cases/50 controls) was conducted at the University College Hospital (UCH) in Ibadan, Nigeria, between October 2011 and December 2012. Men aged 40 to 80 years were approached for the study and asked to provide informed consent and complete the research protocol. Logistic regression models were used to examine associations between demographic, social and lifestyle characteristics and risk of PrCa. Results The participation rate among cases and controls was 98% and 93%, respectively. All participants completed a questionnaire and 99% (50 cases/49 controls) provided blood samples. Cases had a median serum diagnostic PSA of 73 ng/ml, and 38% had a Gleason score 8–10 tumor. Family history of PrCa was associated with a 4.9-fold increased risk of PrCa (95% CI 1.0 - 24.8). There were statistically significant inverse associations between PrCa and height, weight and waist circumference, but there was no association with body mass index (kg/m2). There were no associations between other socio-demographic and lifestyle characteristics and PrCa risk. Conclusion This feasibility study demonstrated the ability to ascertain and recruit participants at UCH and collect epidemiological, clinical and biospecimen data. Our results highlighted the advanced clinical characteristics of PrCa in Nigerian men, and that family history of PrCa and some anthropometric factors were associated with PrCa risk in this population. However, larger studies are needed to better understand the epidemiological risk factors of PrCa in Nigeria.

Objective: Cyberharassment/cyberbullying is a global problem that has been inadequately investigated in developing countries. In this paper, we present findings on the prevalence and predictors of perpetration of cyberbullying among in-school adolescents in Oyo state, Nigeria. Methods: A total of 653 students were selected via multi-stage sampling. Information on history of perpetrating harassment via an electronic medium in the 3-month period preceding the survey was obtained. Results: Respondents’ mean age was 14.2±2.2 years and 51.3% were females. All respondents had personal mobile phones and about half had Internet access. About 40% accessed the Internet every day while about 48% accessed it at least once to several times a week and Conclusion: About a quarter of students were perpetrators of cyberbullying, and the correlates of perpetration were history of cyber victimization and daily Internet access. Intervention programs must be instituted for victims as well as frequent users of the Internet to curb the problem in the study area.

Plasmodium falciparum malaria remains a major public health hazard in sub-Saharan African children. While the factors that determine the variations in clinical outcome of a malaria have not been completely defined, both host and parasite factors, as well as the complex molecular interactions between them have been implicated. The cyto-adherent properties of the P. falciparum -infected red blood cells are considered as key properties in the pathogenesis of malaria and the polymorphisms of the host adhesion molecules could contribute to the severity of malaria. Clinical information and blood samples were collected from 223 children from Ibadan (south-west Nigeria), median age of 34.5 months, presenting with different clinical manifestations of malaria—clinically asymptomatic parasitism (ACP), acute uncomplicated malaria (UM) and severe malaria (SM)—as defined by WHO criteria. The polymorphisms of genes coding for four human adhesion molecules at six different loci (ICAM-1 exons 2, 4 and 6, E-selectin exon 2, CD36 exon 10, and PECAM exon 3) were studied. DNA samples were prepared for further genotyping of the six exons mentioned above by PCR-RFLPs using the appropriate restriction digests for each loci. The ICAM-1 exon 4 locus was monomorphic. All the other loci were at Hardy-Weinberg equilibrium (HWE).The E-selectin locus had very low heterozygosity (∼0.06) in contrast to the other loci under study (0.23–0.44). Once the data was further processed for covariates (age and parasite density) and taking as the reference category the ACP group, results show that in the presence of the G allele at the ICAM-1 exon 6 there is an increased risk (3.6 times) of severe malaria. As far as the T allele in the E-selectin exon is concerned, the number of sampled DNAs with the T allele within both the UM and SM categories is too low for drawing any relevant conclusion at this stage. In conclusion, these results suggest that genetic polymorphisms at host adhesion molecules loci are an important variable in the susceptibility to severe malaria. Further studies of host loci are needed to further delineate which polymorphisms are associated with severe malaria and increase our knowledge of the biology of host-parasite interactions.

Background Child car-passenger safety practices remain low in Nigeria. We present findings from the formative phase of a project to deliver an m-health intervention on child-passenger safety to mothers/caregivers attending selected child-immunisation clinics in Ibadan. The aims were to describe: current legal provisions and awareness of child-passenger safety measures, acceptability of a mobile-phone intervention to improve child-passenger safety and availability and costs of standard age-appropriate child seats. Methods Twenty-three key-informant interviews [with enforcement officers (4), doctors (3), teachers (3) and mothers of infants and school-age children (11)] and a market survey were conducted. Data were analysed with ATLAS.ti. Results Current laws do not directly address child safety although the Highway Code stipulates that child-passengers should be restrained in age-appropriate seats and those ≤12years should sit at the back. Most interviewees were aware of the need to use infant seats but not of the need for child-and booster seats. Some barriers to the use of child carseats were lack of knowledge of its importance and cost. Interviewees felt enactment and enforcement of laws and enlightenment were necessary for compliance. Acceptance of a mobile-phone intervention, (although not necessarily a mobile application), was very high. Participants stated that it was cost-effective and convenient. Interviewees suggested the use of calls, bulk SMS, twitter® and facebook®. Twelve retail stores selling items for children were visited. Most stores had about two to three seats each because of low demand. Barely-used and brand new age-appropriate seats were available although infant seats were mostly seen. Most seats had appropriate standard labels. One barely-used booster seat (cost:$30) was seen. Costs of infant seats ranged from $25 – $180 and toddler seats, $30 – $405. Conclusions Findings indicate that an m-health intervention is acceptable and would be timely in improving car-passenger safety practices among the study participants.

Background Dating Violence (DV) is a major public health problem among adolescents and Female Adolescents (FA) are particularly at risk of becoming victims. Current study described socio-demographic determinants of DV among female victims. This information would help in formation and evaluation of programs that would promote the health and right of FA. Methods This was cross-sectional in design, conducted in Ido Local Government Area, Oyo State, Nigeria. Using two-stage sampling technique, 595 females were recruited from senior classes in private and government-owned secondary schools. Interviewer-administered questionnaire was used to obtain information on socio-demographic characteristics and history of experiencing DV in the three month period preceding the study. Three domains of DV (physical assault, sexual coercion and injury) were assessed using a modified Conflict Tactics Scales 2. Descriptive statistics and Chi-square test (level of significance = 5%) were conducted. Results Mean age of respondents was 15.7 ± 1.6 years. About half (45.9%) had ever dated and 45.2% were currently dating. Among those who had dated, 54.9% experienced at least one incident of DV. Forms of DV experienced were physical assault (46.5%), sexual coercion (27.1%) and injury (8.8%). Younger ( Conclusions The important role age, family type, school type and dating status played in DV victimisation poses the need for programmers to pay robust attention to FA in these categories when designing programs to address this problem.

Chloroquine resistance of Plasmodium falciparum in vitro was significantly higher in isolates from patients with severe malaria than those with uncomplicated disease. This association may be due to either progression of uncomplicated to severe disease following chloroquine failure or increased virulence of chloroquine-resistant parasites. The implication of this for antimalarial treatment policy is discussed.

Large-scale studies of genomic variation could assist efforts to eliminate malaria. But there are scientific, ethical and practical challenges to carrying out such studies in developing countries, where the burden of disease is greatest. The Malaria Genomic Epidemiology Network (MalariaGEN) is now working to overcome these obstacles, using a consortial approach that brings together researchers from 21 countries. © 2008 Macmillan Publishers Limited. All rights reserved.

Background Early diagnosis and prompt treatment including appropriate home-based treatment of malaria is a major strategy for malaria control. A major determinant of clinical outcome in case management is compliance and adherence to effective antimalarial regimen. Home-based malaria treatment with inappropriate medicines is ineffective and there is insufficient evidence on how this contributes to the outcome of severe malaria. This study evaluated the effects of pre-hospital antimalarial drugs use on the presentation and outcome of severe malaria in children in Ibadan, Nigeria. Methods Two hundred and sixty-eight children with a median age of 30 months comprising 114 children with cerebral malaria and 154 with severe malarial anaemia (as defined by WHO) were prospectively enrolled. Data on socio-demographic data, treatments given at home, clinical course and outcome of admission were collected and analysed. Results A total of 168 children had treatment with an antimalarial treatment at home before presenting at the hospital when there was no improvement. There were no significant differences in the haematocrit levels, parasite counts and nutritional status of the pre-hospital treated and untreated groups. The most commonly used antimalarial medicine was chloroquine. Treatment policy was revised to Artemesinin-based Combination Therapy (ACT) in 2005 as a response to unacceptable levels of therapeutic failures with chloroquine, however chloroquine use remains high. The risk of presenting as cerebral malaria was 1.63 times higher with pre-hospital use of chloroquine for treatment of malaria, with a four-fold increase in the risk of mortality. Controlling for other confounding factors including age and clinical severity, pre-hospital treatment with chloroquine was an independent predictor of mortality. Conclusion This study showed that, home treatment with chloroquine significantly impacts on the outcome of severe malaria. This finding underscores the need for wide-scale monitoring to withdraw chloroquine from circulation in Nigeria and efforts intensified at promoting prompt treatment with effective medicines in the community.

Genetic characteristics of Plasmodium falciparum may play a role in the clinical severity of malaria infection. We have studied the association between diversity at the merozoite surface protein-1 (msp-1) locus and the severity of disease in childhood malaria in Ibadan, south-west Nigeria. Two hundred and twenty-three children (median age of 34.5 months) presenting with malaria were enrolled into the study. They comprised 53 children with asymptomatic malaria (ASM), 101 with acute uncomplicated malaria (UM) and 69 with severe malaria (SM). Genotyping of the msp-1 locus was by polymerase chain reaction. The distribution of msp-1 alleles was significantly different between the three groups. Asymptomatic malaria samples had a higher median number of alleles than the other two groups. The type of msp-1 allele detected was significantly associated with the clinical category of malaria. The absence of K1 alleles was associated with a three-fold increase risk of UM and a four-fold increased risk of SM when compared with asymptomatic malaria. The absence of MAD20 alleles was associated with a five-fold increase risk of UM and an eight-fold increase of SM. We have found an association between the msp-1 locus of P. falciparum and clinical severity of malaria in a sample of Nigerian children. Our findings show that the presence of the K1 and MAD20 alleles was significantly associated with ASM and consequently a reduced risk of developing the symptomatic disease.

Falciparum malaria is a leading cause of morbidity and mortality in endemic regions of the world. In areas of intense transmission of P. falciparum children less than the age of 5 years are the most susceptible to severe malaria. The complex interactions between the parasite the human host the vector and environment or social factors may influence the outcome of a malaria infection (White & Ho 1992). Control measures have been based on wide-scale attempts at the reduction in transmission with anti-vector measures and therapeutic management of clinical disease. In sub-Saharan Africa however control is mainly focused on management of the clinical disease and more recently on the use of intermittent preventive treatment (IPT) in pregnant women. Individual preventive measures such as the use of mosquito repellants and the use of insecticide treated bed nets (ITNs) and curtains also influence the risk of host-vector contact host infection and consequently mortality especially in children susceptible to the severe forms of the disease. (excerpt)

Intraleucocytic malaria pigment has been suggested as a measure of disease severity in malaria. We have tested this hypothesis by studying 146 children aged 6 months to 14 years in 4 categories--cerebral malaria, mild malaria, asymptomatic malaria and 'no malaria'--in Ibadan, Nigeria, an area of intense malaria transmission in Africa. Children with cerebral malaria were studied at the university hospital, those with mild malaria at 2 primary health centres and the other 2 groups were studied in a primary school. The proportion of pigment-containing neutrophils showed a clear rise across the spectrum no malaria--asymptomatic malaria--mild malaria--cerebral malaria (median values 2.0%, 6.5%, 9.0% and 27.0%, respectively; P0.0001). The proportion of pigment-containing monocytes did not differ significantly between the mild malaria, asymptomatic malaria and no malaria groups but the cerebral malaria group had a higher median value than the other 3 groups. The ratio of pigment-containing neutrophils to pigment-containing monocytes showed the same trend across the groups of subjects as was observed with the number of pigment-containing neutrophils. It is concluded that the pigment-containing neutrophil count is a simple marker of disease severity in childhood malaria in addition to the parasite count.