Malaria infection and severe disease risks in Africa.
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ABSTRACT:
SUBMITTER: Paton RS
PROVIDER: S-EPMC7611598 | biostudies-literature | 2021 Aug
REPOSITORIES: biostudies-literature
Publications
Malaria infection and severe disease risks in Africa.
Paton Robert S RS Kamau Alice A Akech Samuel S Agweyu Ambrose A Ogero Morris M Mwandawiro Charles C Mturi Neema N Mohammed Shebe S Mpimbaza Arthur A Kariuki Simon S Otieno Nancy A NA Nyawanda Bryan O BO Mohamed Amina F AF Mtove George G Reyburn Hugh H Gupta Sunetra S Bejon Philip P Lourenço José J Snow Robert W RW
Science (New York, N.Y.) 20210801 6557
The relationship between community prevalence of <i>Plasmodium falciparum</i> and the burden of severe, life-threatening disease remains poorly defined. To examine the three most common severe malaria phenotypes from catchment populations across East Africa, we assembled a dataset of 6506 hospital admissions for malaria in children aged 3 months to 9 years from 2006 to 2020. Admissions were paired with data from community parasite infection surveys. A Bayesian procedure was used to calibrate unc ...[more]
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Project description:BackgroundIn Plasmodium falciparum infection, clinical conditions such as anaemia, thrombocytopenia and leukocytosis are common. Mutation in haemoglobin sub-unit beta gene (HBB) may be a genetic factor responsible for these haematological changes during infection. However, the contributions of the carriage of different HBB genotypes on these changes remain largely unknown.MethodologyIn this cross-sectional study, we evaluated haematological abnormalities in P. falciparum-infected children (n = 217, aged 1-192 months) with different haemoglobin sub-unit beta (HBB) genotypes (HbAA, HbAS and HbSS). Children with acute febrile conditions were recruited at Jaramogi Oginga Odinga Teaching and Referral Hospital at the outpatient clinic. Haematological parameters were determined using Beckman Coulter counter ACTdiff2™ while HBB genotyping was done using TaqMan® SNP genotyping assay. Chi-square (χ2) was used to determine differences between proportions. Differences in haematological parameters were compared across groups using Kruskal Wallis test and between groups using Mann Whitney U test. Partial correlation test was used to determine correlation between haematological parameters and sickle cell genotypes while controlling for age and sex.ResultsHaemoglobin (Hb), [median (IQR); 7.3 (1.3), P = 0.001], haematocrit (HCT), [median (IQR); 26.4 (4.4), P = 0.009], red blood cells (RBC), [median (IQR); 3.2 (1.7), P = 0.048] were markedly reduced in HbSS, however, red cell distribution with (RDW) [median (IQR); 14.9 (3.3), P = 0.030] was increased in malaria infected children with HbSS. Severe anaemia was highest in HbSS (23.1%) followed by HbAA (8.6%) and HbAS (7.1%). There were no differences in platelet count (P = 0.399) hence no severe thrombocytopeania across the genotypes. Leukocytosis was highest in HbSS (69.2%), 42% in HbAS and 31% in HbAA. The RBC, HCT and Hb had negative correlation with RDW in HbSS in malarial-infected children (r = - 0.725, P = 0.008), (r = - 0.718, P = 0.009) and (r = - 0.792, P = 0.002), respectively.ConclusionOur study reveals that anaemia is the most common abnormality in malaria-infected children with carriage of HbSS. The RBC, HCT and Hb concentration decrease with increase in RDW levels in infected children with carriage of HbSS compared to other HBB genotypes. Therefore, carriage of HbSS genotype is correlated with severity of haematological abnormalities.
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Project description:Background Use of community health workers (CHWs) to increase access to diagnosis and treatment of malaria is recommended by the World Health Organization. The present article reports on training and performance of CHWs in applying these recommendations.Methods Two hundred seventy-nine CHWs were trained for 3-5 days in Burkina Faso, Nigeria, and Uganda, and 19 were certified to diagnose and treat only uncomplicated malaria and 235 to diagnose and treat both uncomplicated and severe malaria. Almost 1 year after training, 220 CHWs were assessed using standard checklists using facility staff responses as the reference standard.Results Training models were slightly different in the 3 countries, but the same topics were covered. The main challenges noticed were the low level of education in rural areas and the involvement of health staff in the supervision process. Overall performance was 98% (with 99% in taking history, 95% in measuring temperature, 85% for measuring respiratory rates, 98% for diagnosis, 98% for classification, and 99% for prescribing treatment). Young, single, new CHWs performed better than their older, married, more experienced counterparts.Conclusions Training CHWs for community-based diagnosis and treatment of uncomplicated and severe malaria is possible with basic and refresher training and close supervision of CHWs' performance.Clinical trials registration ISRCTRS13858170.
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