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Trop. Dis"],"abstract":"<jats:p>To better understand the factors underlying the continued incidence of clinical episodes of falciparum malaria in E-2025 countries targeting elimination, we characterized the molecular epidemiology of<jats:italic>Plasmodium falciparum<\/jats:italic>disease transmission after a clonal outbreak in Ecuador. Here we study disease transmission by documenting the diversity and population structure of the major variant surface antigen of the blood stages of<jats:italic>P. falciparum<\/jats:italic>encoded by the<jats:italic>var<\/jats:italic>multigene family. We used a high-resolution genotyping method, \u201c<jats:italic>var<\/jats:italic>coding\u201d, involving targeted amplicon sequencing to fingerprint the DBL\u03b1 encoding region of<jats:italic>var<\/jats:italic>genes to describe both antigenic<jats:italic>var<\/jats:italic>diversity and<jats:italic>var<\/jats:italic>repertoire similarity or relatedness in parasite isolates from clinical cases. We identified nine genetic<jats:italic>var<\/jats:italic>codes in 58<jats:italic>P. falciparum<\/jats:italic>isolates causing clinical disease in 2013-2015. Network analyses revealed that four of the<jats:italic>var<\/jats:italic>codes were highly related to the outbreak<jats:italic>var<\/jats:italic>code, with identification of possible diversification of the outbreak parasites by recombination as seen in three of those<jats:italic>var<\/jats:italic>codes. The majority of clinical cases in Ecuador were associated with parasites with highly related or recombinant<jats:italic>var<\/jats:italic>codes to the outbreak clone and due to local transmission rather than recent importation of parasites from other endemic countries. Sharing of types in Ecuadorian<jats:italic>var<\/jats:italic>codes to those sampled in South American<jats:italic>var<\/jats:italic>codes reflects historical parasite importation of some<jats:italic>var<\/jats:italic>codes, especially from Colombia and Peru. Our findings highlight the translational application of<jats:italic>var<\/jats:italic>coding for outbreak surveillance in epidemic\/unstable malaria transmission, such as in E-2025 countries, and point to the need for surveillance of local reservoirs of infection in Ecuador to achieve the malaria elimination goal by 2025.<\/jats:p>","DOI":"10.3389\/fitd.2023.1085862","type":"journal-article","created":{"date-parts":[[2023,3,17]],"date-time":"2023-03-17T05:45:11Z","timestamp":1679031911000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":10,"title":["Molecular epidemiology of continued Plasmodium falciparum disease transmission after an outbreak in Ecuador"],"prefix":"10.3389","volume":"4","author":[{"given":"Shazia","family":"Ruybal-Pes\u00e1ntez","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fabi\u00e1n 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