Background: Persistence of sulfadoxine-pyrimethamine (SP) resistance has been described in an urban setting in Malawi where malaria transmission is relatively low. Higher malaria transmission is associated with greater genetic diversity and more frequent genetic recombination, which could lead to a more rapid re-emergence of SP-sensitive parasites, as well as more rapid degradation of selective sweeps. In this study, the impact of local variation in malaria transmission on the prevalence of SP-resistant haplotypes and selective sweep characteristics was investigated at an urban site with low parasite prevalence and two rural sites with moderate and high parasite prevalence.
Methods: Samples from three sites with different parasite prevalence were genotyped for resistance markers within pfdhfr-ts and pfdhps and at microsatellites flanking these genes. Expected heterozygosity (He) was estimated to evaluate genetic diversity.
Results: No difference in the prevalence of highly resistant DHFR 51I/59R/108N and DHPS 437G/540E was found between sites. Small differences in He flanking pfdhfr-ts and pfdhps were seen between rural-moderate and the other sites, as well as some shared haplotypes between the rural-high and urban-low sites.
Conclusions: The results do not show an effect of local variation in malaria transmission, as inferred from parasite prevalence, on SP-resistant haplotype prevalence.
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http://dx.doi.org/10.1186/s12936-015-0860-7 | DOI Listing |
Background: The WHO malaria treatment guidelines recommend a total dose in the range of 3·5 to 7·0 mg/kg of primaquine to eliminate ( ) hypnozoites and prevent relapses. There are however indications that for tropical isolates, notably from Southeast Asia, the lower dose of 3·5 mg/kg is insufficient. Determining the most effective regimen to eliminate hypnozoites is needed to achieve elimination of this malaria parasite.
View Article and Find Full Text PDFIncreasing artemisinin partial resistance (ArtR) due to mutations in the gene encoding Kelch13 ( ) protein in eastern Africa is of urgent concern, and mutations, such as P441L, continue to emerge. We used an amplicon deep-sequencing panel to estimate the prevalence of ArtR mutations in samples collected between 2018 and 2023 in southern Zambia. P441L was present in 30 of 501 samples (6%), and prevalence increased over time (0% to 7.
View Article and Find Full Text PDFEur J Public Health
January 2025
Health Protection and Communicable Diseases Control Department, Ministry of Public Health, Doha, Qatar.
Preventing local transmission of malaria from imported cases is crucial for achieving and maintaining malaria elimination. This study aimed to investigate the epidemiological characteristics of imported malaria cases and assess the distribution of malaria vectors in Qatar. Data from January 2016 to December 2022 on imported malaria, including demographic and epidemiological characteristics, travel-related information, and diagnostic results, were collected and analysed using descriptive statistics.
View Article and Find Full Text PDFEur J Public Health
January 2025
Department of Community Health, Amref International University, Nairobi, Kenya.
The Chikungunya virus (CHIKV) presents substantial public health challenges in the Eastern Mediterranean Region (EMR), with its prevalence and interaction with other arboviruses (ABVs) remaining poorly understood. This systematic review and meta-analysis aimed to assess the prevalence of CHIKV and its association with other ABVs, such as dengue virus (DENV), Rift Valley fever virus (RVFV), malaria, and yellow fever virus (YFV), in the EMR. We systematically searched databases including PubMed, Embase, Web of Science, Scopus, Cochrane Library, CINAHL, PsycINFO, and ScienceDirect to identify epidemiological studies that report CHIKV prevalence and provide odds ratios (ORs) for CHIKV compared to other ABVs.
View Article and Find Full Text PDFMalar J
January 2025
Centre for Biotechnology Research and Development, Kenya Medical Research Institute (KEMRI), Nairobi, Kenya.
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