Tackling malaria transmission at a single cell level in an endemic setting in sub-Saharan Africa

A single cell atlas of sexual development in Plasmodium falciparum

The developmental decision made by malaria parasites to become sexual underlies all malaria transmission. Here, we describe a rich atlas of short- and long-read single-cell transcriptomes of over 37,000 Plasmodium falciparum cells across intraerythrocytic asexual and sexual development. We used the atlas to explore transcriptional modules and exon usage along sexual development and expanded it to include malaria parasites collected from four Malian individuals naturally infected with multiple P. falciparum strains. We investigated genotypic and transcriptional heterogeneity within and among these wild strains at the single-cell level, finding differential expression between different strains even within the same host. These data are a key addition to the Malaria Cell Atlas interactive data resource, enabling a deeper understanding of the biology and diversity of transmission stages.

Overcoming barriers to single-cell RNA sequencing adoption in low- and middle-income countries

The advent of single-cell resolution sequencing and spatial transcriptomics has enabled the delivery of cellular and molecular atlases of tissues and organs, providing new insights into tissue health and disease. However, if the full potential of these technologies is to be equitably realised, ancestrally inclusivity is paramount. Such a goal requires greater inclusion of both researchers and donors in low- and middle-income countries (LMICs). In this perspective, we describe the current landscape of ancestral inclusivity in genomic and single-cell transcriptomic studies. We discuss the collaborative efforts needed to scale the barriers to establishing, expanding, and adopting single-cell sequencing research in LMICs and to enable globally impactful outcomes of these technologies.

Prediction of malaria positivity using patients' demographic and environmental features and clinical symptoms to complement parasitological confirmation before treatment

BACKGROUND

Current malaria diagnosis methods that rely on microscopy and Histidine Rich Protein-2 (HRP2)-based rapid diagnostic tests (RDT) have drawbacks that necessitate the development of improved and complementary malaria diagnostic methods to overcome some or all these limitations. Consequently, the addition of automated detection and classification of malaria using laboratory methods can provide patients with more accurate and faster diagnosis. Therefore, this study used a machine-learning model to predict Plasmodium falciparum (Pf) antigen positivity (presence of malaria) based on sociodemographic behaviour, environment, and clinical features.

METHOD

Data from 200 Nigerian patients were used to develop predictive models using nested cross-validation and sequential backward feature selection (SBFS), with 80% of the dataset randomly selected for training and optimisation and the remaining 20% for testing the models. Outcomes were classified as Pf-positive or Pf-negative, corresponding to the presence or absence of malaria, respectively.

RESULTS

Among the three machine learning models examined, the penalised logistic regression model had the best area under the receiver operating characteristic curve for the training set (AUC = 84%; 95% confidence interval [CI]: 75-93%) and test set (AUC = 83%; 95% CI: 63-100%). Increased odds of malaria were associated with higher body weight (adjusted odds ratio (AOR) = 4.50, 95% CI: 2.27 to 8.01, p < 0.0001). Even though the association between the odds of having malaria and body temperature was not significant, patients with high body temperature had higher odds of testing positive for the Pf antigen than those who did not have high body temperature (AOR = 1.40, 95% CI: 0.99 to 1.91, p = 0.068). In addition, patients who had bushes in their surroundings (AOR = 2.60, 95% CI: 1.30 to 4.66, p = 0.006) or experienced fever (AOR = 2.10, 95% CI: 0.88 to 4.24, p = 0.099), headache (AOR = 2.07; 95% CI: 0.95 to 3.95, p = 0.068), muscle pain (AOR = 1.49; 95% CI: 0.66 to 3.39, p = 0.333), and vomiting (AOR = 2.32; 95% CI: 0.85 to 6.82, p = 0.097) were more likely to experience malaria. In contrast, decreased odds of malaria were associated with age (AOR = 0.62, 95% CI: 0.41 to 0.90, p = 0.012) and BMI (AOR = 0.47, 95% CI: 0.26 to 0.80, p = 0.006).

CONCLUSION

Newly developed routinely collected baseline sociodemographic, environmental, and clinical features to predict Pf antigen positivity may be a valuable tool for clinical decision-making.

CO-INFECTION WITH MALARIA AND INTESTINAL PARASITES AND ITS ASSOCIATION WITH ANEMIA IN CHILDREN (ZERO TO TEN YEARS OLD) IN TIKO SUBDIVISION, CAMEROON

Concomitant infections with malaria and intestinal parasitic infections may be associated with anemia in children (0-10 yr). This study determined the prevalence of co-infection with malaria and intestinal parasitic infections and determined its association with anemia in children (0-10 yr) in Tiko, Cameroon. A hospital-based cross-sectional study was carried out whereby venous blood and stool samples were collected from 377 febrile children. Blood was used to perform a full blood count. Thick and thin blood films were prepared and stained with Giemsa for malaria parasite diagnosis. The formol ether concentration technique was used to analyze the stools. Pearson's chi-square test, Student's t-test, and other statistical analyses were performed. Of the 377 participants, 139 (36.9%) were positive for malaria, 21 (5.6%) had intestinal helminths, 8 (2%) had co-infection, and 79 (21.0%) were anemic. Malaria and anemia were prevalent among the children and were significantly associated (P = 0.025). There was no statistically significant difference (P > 0.05) among age groups. Girls were more often infected with malaria (69, 37.3%), and boys were more often infected with intestinal parasites (13, 7.0%), but there was no statistical association for both malaria and intestinal parasitic infections (IPIs) for both sexes (P > 0.05). Hookworms, Ascaris lumbricoides, and Trichuris trichiura were the intestinal parasites found in this study. There was a significant association between anemia and parasitic co-infection in children (P = 0.003). Malaria and IPIs are prevalent in the Tiko municipality. They play a great role in anemia especially when there is a co-infection. Public education and awareness campaigns are necessary in this municipality.