Background: Deletion of pfhrp2 and/or pfhrp3 genes cause false negatives in malaria rapid diagnostic test (RDT) and threating malaria control strategies. This systematic review aims to assess the main methodological aspects in the study of pfhrp2 and pfhrp3 gene deletions and its global epidemiological status, with special focus on their distribution in Africa; and its possible impact in RDT. Methods: The systematic review was conducted by examining the principal issues of study design and methodological workflow of studies addressing pfhrp2 deletion. Meta-analysis was applied to represent reported prevalences of pfhrp2 and pfhrp3 single and double deletion in the World Health Organization (WHO) region. Pooled-prevalence of deletions was calculated using DerSimonnian-Laird random effect model. Then, in-deep analysis focused on Africa was performed to assess possible variables related with these deletions. Finally, the impact of these deletions in RDT results was analysed combining reported information about RDT sensitivity and deletion prevalences. Results: 49 articles were included for the systematic review and 37 for the meta-analysis, 13 of them placed in Africa. Study design differs significantly, especially in terms of population sample and information reported, resulting in high heterogeneity between studies that difficulties comparisons and merged conclusions. Reported prevalences vary widely in all the WHO regions, significantly higher deletion were reported in South-Central America, following by Africa and Asia. Pfhrp3 deletion is more prevalent (43% in South-Central America; 3% in Africa; and 1% in Asia) than pfhrp2 deletion (18% in South-Central America; 4% in Africa; and 3% in Asia) worldwide. In Africa, there were not found differences in deletion prevalence by geographical or population origin of samples. The prevalence of deletion among false negatives ranged from 0 to 100% in Africa, but in Asia and South-Central America was only up to 90% and 48%, respectively, showing substantial relation between deletions and false negatives. Conclusion: The concerning prevalence of pfhrp2, pfhrp3 and pfhrp2/3 gene deletions, as its possible implications in malaria control, highlights the importance of regular and systematic surveillance of these deletions. This review has also outlined that a standardized methodology could play a key role to ensure comparability between studies to get global conclusions.

Background: Although rapid diagnostic tests (RDTs) play a key role in malaria-control strategies, their efficacy has been threatened by deletion and genetic variability of the genes pfhrp2/3. This study aims to characterize the deletion, genetic patterns and diversity of these genes and their implication for malaria RDT effectiveness, as well as their genetic evolution in the Amhara region of Ethiopia. Methods: The study included 354 isolates from symptomatic patients from the Amhara region of Ethiopia who tested positive by microscopy. Exon 1–2 and exon 2 of genes pfhrp2 and -3 were amplified, and exon 2 was sequenced to analyse the genetic diversity, phylogenetic relationship and epitope availability. Results: The deletion frequency in exon 1–2 and exon 2 was 22 and 4.6% for pfhrp2, and 68 and 18% for pfhrp3, respectively. Double deletion frequency for pfhrp2 and pfhrp3 was 1.4%. High genetic diversity, lack of clustering by phylogenetic analysis and evidence of positive selection suggested a diversifying selection for both genes. The amino-acid sequences, classified into different haplotypes, varied widely in terms of frequency of repeats, with novel amino-acid changes. Aminoacidic repetition type 2 and type 7 were the most frequent in all the sequences. The most frequent epitopes among protein sequences were those recognized by MAbs 3A4 and C1-13. Conclusion: Deletions and high amino acidic variation in pfhrp2 and pfhrp3 suggest their possible impact on RDT use in the Amhara region, and the high genetic diversity of these genes could be associated with a diversifying selection in Ethiopia. Surveillance of these genes is, therefore, essential to ensure the effectiveness of public health interventions in this region. Graphical

: Artemisinin-combined treatments are the recommended first-line treatment of Plasmodium falciparum malaria, but they are being threatened by emerging artemisinin resistance. Mutations in pfk13 are the principal molecular marker for artemisinin resistance. This study characterizes the presence of mutations in pfk13 in P. falciparum in Western Equatoria State, South Sudan. We analyzed 468 samples from patients with symptomatic malaria and found 15 mutations (8 nonsynonymous and 7 synonymous). Each mutation appeared only once, and none were validated or candidate markers of artemisinin resistance. However, some mutations were in the same or following position of validated and candidate resistance markers, suggesting instability of the gene that could lead to resistance. The R561L nonsynonymous mutation was found in the same position as the R561H validated mutation. Moreover, the A578S mutation, which is widespread in Africa, was also reported in this study. We found a high diversity of other pfk13 mutations in low frequency. Therefore, routine molecular surveillance of resistance markers is highly recommended to promptly detect the emergence of resistance-related mutations and to limit their spread.

Objective Description of tuberculosis (TB)-focused point-of-care ultrasound (POCUS) findings for children with presumptive TB. Design Cross-sectional study (July 2019 to April 2020). Setting Simão Mendes hospital in Bissau, a setting with high TB, HIV, and malnutrition burdens. Participants Patients aged between 6 months and 15 years with presumptive TB. Interventions Participants underwent clinical, laboratory and unblinded clinician-performed POCUS assessments, to assess subpleural nodules (SUNs), lung consolidation, pleural and pericardial effusion, abdominal lymphadenopathy, focal splenic and hepatic lesions and ascites. Presence of any sign prompted a POCUS positive result. Ultrasound images and clips were evaluated by expert reviewers and, in case of discordance, by a second reviewer. Children were categorised as confirmed TB (microbiological diagnosis), unconfirmed TB (clinical diagnosis) or unlikely TB. Ultrasound findings were analysed per TB category and risk factor: HIV co-infection, malnutrition and age. Results A total of 139 children were enrolled, with 62 (45%) women and 55 (40%) aged <5 years; 83 (60%) and 59 (42%) were severely malnourished (SAM) and HIV-infected, respectively. TB confirmation occurred in 27 (19%); 62 (45%) had unconfirmed TB and 50 (36%) had unlikely TB. Children with TB were more likely to have POCUS-positive results (93%) compared with children with unlikely TB (34%). Common POCUS signs in patients with TB were: lung consolidation (57%), SUNs (55%) and pleural effusion (30%), and focal splenic lesions (28%). In children with confirmed TB, POCUS sensitivity was 85% (95% CI) (67.5% to 94.1%). In those with unlikely TB, specificity was 66% (95% CI 52.2% to 77.6%). Unlike HIV infection and age, SAM was associated with a higher POCUS-positivity. Cohen’s kappa coefficient for concordance between field and expert reviewers ranged from 0.6 to 0.9. Conclusions We found a high prevalence of POCUS signs in children with TB compared with children with unlikely TB. POCUS-positivity was dependent on nutritional status but not on HIV status or age. TB-focused POCUS could potentially play a supportive role in the diagnosis of TB in children. Trial registration number NCT05364593.

This study describes the alcohol environment comparing residents’ perceptions and objective measures in two different income-level districts. Measures were gathered between 2017 and 2018 in two districts with different income levels in Madrid, Spain. We obtained perceived measures using Photovoice. We procured objective measures through social systematic observation. Data were integrated using triangulation. Perceived and objective measures of the alcohol environment were characterized and compared in terms of alcohol availability, alcohol promotion, and signs of alcohol consumption. The integration was classified as agreement, partial agreement, or dissonance. The results related to alcohol availability and signs of its consumption showed high agreement. Availability was high in both areas, which was recognized by residents. Residents of the high-income district (HID) discussed fewer signs of alcohol consumption, whilst those in the low-income district (LID) reported extensive signs of consumption. Such observations agreed with the objective measures. There were dissonances between the approaches for alcohol promotion. Although the alcohol promotion was higher in HID according to the objective measures, it was deeply discussed by LID residents. Both methodologies helped us deepen the understanding of the alcohol environment. These results may help design more effective interventions to prevent hazardous drinking.