Transcriptome-module phenotype association study implicates extracellular vesicles biogenesis in Plasmodium falciparum artemisinin resistance.

Plasmodium falciparum malaria is still an important disease in sub-Saharan Africa (sSA). Great strides have been made in its control spear-headed by artemisinin (ART)-based combination therapies (ACTs). However, concerns about the imminent spread of ART-resistant (ARTr) malaria parasites to sSA threaten gains already made. Attempts to mitigate this risk have highlighted the need to discover novel P. falciparum drug targets. Therefore, studies to deepen our understanding of the biology of P. falciparum are needed. The role of extracellular vesicles (EVs) in the biology of malaria parasites is not fully understood. Recently, the ART resistance-associated transcriptional profile has been reported to involve several biological processes connected to vesicular trafficking, proteotoxic stress, erythrocyte remodelling, and mitochondrial metabolism. We explored a role for EVs in developing the P. falciparum ARTr phenotype using bulk RNA sequencing of unsynchronized parasite cultures under untreated, 0.1% dimethyl sulfoxide and 700nM dihydroartemisinin treated conditions for six hours. As pathway and gene ontology analysis is limited in its curated knowledge repertoire on EVs biogenesis in P. falciparum, we used a modular (gene set) analysis approach to explore whether an EVs biogenesis module is associated with the ARTr phenotype in P. falciparum. We first generated well-defined EVs modules of interest and used statistical tools to determine differences in their expression among the parasite and treatment conditions. Then we used gene set enrichment analysis to determine the strength of the association between each EVs module of interest and the ARTr phenotype. This transcriptome-module phenotype association study (TMPAS) represents a well-powered approach to making meaningful discoveries out of bulk gene expression data. We identified four EVs module of interest and report that one module representing gene sets with correlated expression to PF3D7_1441800 - involved with EVs biogenesis in P. falciparum - is associated with the ARTr phenotype (R539T_DHA_treated versus R539T_untreated: normalized enrichment score (NES) = 1.1830174, FDR q-value < 0.25; C580R_DHA_treated versus C580R_untreated: NES = 1.2457103, FDR q-value < 0.25). PF3D7_1441800 has been reported to reduce EVs production when knocked out in P. falciparum. Altogether, our findings suggest a role for EVs in developing ART resistance and warrant further studies interrogating this association.

Unravelling the Perspectives of Day and Night Traders in Selected Markets within a Sub-Saharan African City with a Malaria Knowledge, Attitude and Practice Survey.

BACKGROUND: Malaria is still endemic in sub-Saharan Africa, with a high disease burden. Misconceptions about malaria contribute to poor attitudes and practices, further increasing the burden in endemic countries. Studies have examined the knowledge, attitudes, and practices (KAP) of malaria among different populations. However, there seems to be no available literature reporting on the perspectives of day and night market traders. To the best of our knowledge, this is the first report on malaria KAP with a focus on day and night market traders. METHODS: A descriptive cross-sectional study involving day and night market traders in 10 selected markets within the Greater Accra Region of Ghana was carried out. Data were collected from consenting respondents using a structured questionnaire. RESULTS: Of the 760 respondents (33.3% (n = 253) night and 66.7% (n = 507) day traders) interviewed, there was no significant difference between the day and night market traders in terms of malaria KAP. Although the market traders had an overall moderate knowledge (54.0% of the day traders and 56.5% of the night traders), misconceptions about malaria (especially that it could be caused by exposure to the sun) still existed among the traders. Moreover, the majority of the traders who demonstrated high knowledge (43.98%, n = 250) did not always take laboratory tests to confirm their suspicion, indicating poor attitude. Furthermore, the market traders' choice of drug for malaria treatment (p = 0.001) and preferred malaria treatment type (orthodox or herbal) (p = 0.005) were significantly associated with their knowledge level. CONCLUSIONS: Despite the observation that no significant difference in KAP exists between day and night market traders, appropriate health education programs and interventions still need to be directed at misconceptions, poor attitudes, and poor practices revealed by this study. This will ultimately help in the prevention and control of malaria in Ghana, and globally.

Anthropometric indices and cardiometabolic risk factors in a Ghanaian adolescent population.

OBJECTIVES: Adolescent overweight and obesity is a public health concern globally, especially in lower- and middle- income countries where there is an additional burden of undernutrition. The prevalence of adolescent overweight/2obesity has increased markedly over the past three decades. The transition in dietary habits coupled with reduced physical activity has been blamed for the increasing trend. Overweight/obesity in adolescence is complicated by cardiometabolic, respiratory, musculoskeletal and psychosocial disorders. Additionally, adolescent obesity is a predictor of future development of type 2 diabetes, cardiovascular diseases and metabolic disorders. The burden of cardiometabolic risk factors associated with adolescent overweight/obesity in Ghana is lacking, the project, therefore, was undertaken to add to the existing knowledge. METHODS: The study was undertaken in adolescent students of a tertiary institution in Ghana. Two hundred and one students consented to participate in the study. Questionnaires on sociodemographic characteristics, dietary and substance abuse habits were self-administered. Blood pressure, height, weight and waist circumference measures were performed and venous blood drawn for the determination of fasting serum total/LDL/HDL cholesterol and triglycerides. Body mass indices were determined as the weight per square of their heights. RESULTS: The prevalence of obesity was determined to be 15.81% generally, 27.71% in the females and 7.08% in the males. Diastolic blood pressure was the only cardiometabolic risk factor significantly associated with obesity in our study. CONCLUSION: Overweight/obesity is common in Ghanaian adolescents, with the prevalence highest in the female population.

Prevalence of Plasmodium falciparum delayed clearance associated polymorphisms in adaptor protein complex 2 mu subunit (pfap2mu) and ubiquitin specific protease 1 (pfubp1) genes in Ghanaian isolates.

BACKGROUND: Plasmodium falciparum delayed clearance with the use of artemisinin-based combination therapy (ACTs) has been reported in some African countries. Single nucleotide polymorphisms (SNPs) in two genes, P. falciparum adaptor protein complex 2 mu subunit (pfap2mu) and ubiquitin specific protease 1 (pfubp1), have been linked to delayed clearance with ACT use in Kenya and recurrent imported malaria in Britain. With over 12 years of ACT use in Ghana, this study investigated the prevalence of SNPs in the pfap2mu and pfubp1 in Ghanaian clinical P. falciparum isolates to provide baseline data for antimalarial drug resistance surveillance in the country. METHODS: Filter paper blood blots collected in 2015-2016 from children aged below 9 years presenting with uncomplicated malaria at hospitals in three sentinel sites Begoro, Cape Coast and Navrongo were used. Parasite DNA was extracted from 120 samples followed by nested polymerase chain reaction (nPCR). Sanger sequencing was performed to detect and identify SNPs in pfap2mu and pfubp1 genes. RESULTS: In all, 11.1% (9/81) of the isolates carried the wildtype genotypes for both genes. A total of 164 pfap2mu mutations were detected in 67 isolates whilst 271 pfubp1 mutations were observed in 72 isolates. The majority of the mutations were non-synonymous (NS): 78% (128/164) for pfap2mu and 92.3% (250/271) for pfubp1. Five unique samples had a total of 215 pfap2mu SNPs, ranging between 15 and 63 SNPs per sample. Genotypes reportedly associated with ART resistance detected in this study included pfap2mu S160N (7.4%, 6/81) and pfubp1 E1528D (7.4%, 6/81) as well as D1525E (4.9%, 4/81). There was no significant difference in the prevalence of the SNPs between the three ecologically distinct study sites (pfap2mu: χ2 = 6.905, df = 2, P = 0.546; pfubp1: χ2 = 4.883, df = 2, P = 0.769). CONCLUSIONS: The detection of pfap2mu and pfubp1 genotypes associated with ACT delayed parasite clearance is evidence of gradual nascent emergence of resistance in Ghana. The results will serve as baseline data for surveillance and the selection of the genotypes with drug pressure over time. The pfap2mu S160N, pfubp1 E1528D and D1525E must be monitored in Ghanaian isolates in ACT susceptibility studies, especially when cure rates of ACTs, particularly AL, is less than 100%.

Impact of universal childhood vaccination against hepatitis B in Ghana: A pilot study.

Hepatitis B virus (HBV) infection is of public health importance worldwide. Vaccination against the infection, especially in early childhood has significantly reduced the public health impact. This pilot study was undertaken in Cape Coast Metropolitan area to assess the impact of the introduction of HBV vaccination in children. A cross-sectional multi-stage cluster sampling of 501 pupils from 30 public and private primary and junior high schools within the Cape Coast metropolis. A questionnaire covering basic demographic details and immunisation history were administered to the participants after consent and assent had been sought. Hepatitis B serological test for HBsAg, HBcAb, HBsAb, HBeAg and HbeAb was undertaken using Hepatitis B test kit and capillary blood from the participants. The general prevalence of HBcAb, HBsAg and HBsAb was found to be 3.6, 2.6 and 19.8% respectively. The prevalence of HBcAb was 2.6 and 6.1% among pupils delivered after and before the vaccine programme introduction respectively. Introduction of the vaccination programme in Ghana has had a positive impact on the HBV infection in Ghana.