Genotypes and phenotypes of resistance in Ecuadorian Plasmodium falciparum.

Malar J

Centro de Investigación para la Salud en América Latina, Facultad de Ciencias Exactas y Naturales, Pontificia Universidad Católica del Ecuador, Av. 12 de Octubre 1076, Apartado, 17-01-2184, Quito, Ecuador.

Published: December 2019

Background: Malaria continues to be endemic in the coast and Amazon regions of Ecuador. Clarifying current Plasmodium falciparum resistance in the country will support malaria elimination efforts. In this study, Ecuadorian P. falciparum parasites were analysed to determine their drug resistance genotypes and phenotypes.

Methods: Molecular analyses were performed to search for mutations in known resistance markers (Pfcrt, Pfdhfr, Pfdhps, Pfmdr1, k13). Pfmdr1 copy number was determined by qPCR. PFMDR1 transporter activity was characterized in live parasites using live cell imaging in combination with the Fluo-4 transport assay. Chloroquine, quinine, lumefantrine, mefloquine, dihydroartemisinin, and artemether sensitivities were measured by in vitro assays.

Results: The majority of samples from this study presented the CVMNT genotype for Pfcrt (72-26), NEDF SDFD mutations in Pfmdr1 and wild type genotypes for Pfdhfr, Pfdhps and k13. The Ecuadorian P. falciparum strain ESM-2013 showed in vitro resistance to chloroquine, but sensitivity to quinine, lumefantrine, mefloquine, dihydroartemisinin and artemether. In addition, transport of the fluorochrome Fluo-4 from the cytosol into the digestive vacuole (DV) of the ESM-2013 strain was minimally detected in the DV. All analysed samples revealed one copy of Pfmdr1.

Conclusion: This study indicates that Ecuadorian parasites presented the genotype and phenotype for chloroquine resistance and were found to be sensitive to SP, artemether-lumefantrine, quinine, mefloquine, and dihydroartemisinin. The results suggest that the current malaria treatment employed in the country remains effective. This study clarifies the status of anti-malarial resistance in Ecuador and informs the P. falciparum elimination campaigns in the country.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6905098PMC
http://dx.doi.org/10.1186/s12936-019-3044-zDOI Listing

Publication Analysis

Top Keywords

mefloquine dihydroartemisinin
12
plasmodium falciparum
8
ecuadorian falciparum
8
pfdhfr pfdhps
8
quinine lumefantrine
8
lumefantrine mefloquine
8
dihydroartemisinin artemether
8
resistance
7
falciparum
5
genotypes phenotypes
4

Similar Publications

Background: The treatment and control of malaria in Africa is challenged by drug resistance, including transporter, folate pathway, and PfK13 mutations that mediate resistance to aminoquinolines, antifolates, and artemisinins, respectively. Characterization of drug susceptibility informs optimal control strategies.

Methods: We characterized ex vivo susceptibilities to nine drugs of isolates collected from individuals presenting with uncomplicated falciparum malaria in eastern (2019-2024) and northern (2021-2024) Uganda using a growth inhibition assay and the dihydroartemisinin (DHA) ring survival assay (RSA).

View Article and Find Full Text PDF

Praziquantel alone is insufficient for the control of schistosomiasis due to poor efficacy against juvenile worms and increasing concerns about the risk of drug resistance. We compared the efficacy and safety of praziquantel combined with four different artemisinin-based combinations to praziquantel alone in treating infection in Kenyan children. In this randomized, open-label, five-arm, head-to-head, non-inferiority trial, children (aged 9-15 years) with infection according to duplicate Kato Katz thick smears from a stool sample in the Mwea irrigation scheme of central Kenya, were enrolled.

View Article and Find Full Text PDF

Intermittent preventive treatment regimens for malaria in HIV-positive pregnant women.

Cochrane Database Syst Rev

September 2024

Maternal, Child and Reproductive Health Initiative, Barcelona Institute for Global Health (ISGlobal), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain.

Background: Malaria and HIV infection overlap geographically in sub-Saharan Africa and share risk factors. HIV infection increases malaria's severity, especially in pregnant women. The World Health Organization (WHO) recommends intermittent preventive treatment in pregnancy (IPTp) with sulphadoxine-pyrimethamine (SP) for pregnant women living in areas of stable malaria transmission.

View Article and Find Full Text PDF

Malaria remains a leading cause of morbidity and mortality in Burkina Faso, which utilizes artemether-lumefantrine as the principal therapy to treat uncomplicated malaria and seasonal malaria chemoprevention with monthly sulfadoxine-pyrimethamine plus amodiaquine in children during the transmission season. Monitoring the activities of available antimalarial drugs is a high priority. We assessed the susceptibility of to 11 drugs in isolates from patients presenting with uncomplicated malaria in Bobo-Dioulasso in 2021 and 2022.

View Article and Find Full Text PDF

Artemisinin resistance-associated gene mutations in Plasmodium falciparum: A case study of severe malaria from Mozambique.

Travel Med Infect Dis

January 2024

Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus de Gualtar, 4710-057, Braga, Portugal; ICVS/3B's─PT Government Associate Laboratory, 4806-909, Guimarães/ Braga, Portugal; Clinical Academic Center-Braga (2CA-Braga), 4710-243, Braga, Portugal. Electronic address:

Background: The effectiveness of artemisinin-based combination therapies (ACT) in treating Plasmodium falciparum, is vital for global malaria control efforts, particularly in sub-Saharan Africa. The examination of imported cases from endemic areas holds implications for malaria chemotherapy on a global scale.

Method: A 45-year-old male presented with high fever, dry cough, diarrhoea and generalized muscle pain, following a two-week trip to Mozambique.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!