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The country of Angola officially replaced CQ with artemisinin-based combination therapy (ACT) as a first-line treatment in 2006, but malaria cases and deaths have recently been rising. Many classic resistance mutations are relevant for the efficacy of currently available drugs, making it important to continue monitoring their frequency in Angola.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      <jats:italic>Plasmodium falciparum<\/jats:italic>\n                      DNA was sampled from the blood of 50 hospital patients in Cabinda, Angola from October-December of 2018. Each infection was genotyped for 13 alleles in the genes\n                      <jats:italic>crt<\/jats:italic>\n                      ,\n                      <jats:italic>mdr1<\/jats:italic>\n                      ,\n                      <jats:italic>dhps<\/jats:italic>\n                      ,\n                      <jats:italic>dhfr<\/jats:italic>\n                      , and\n                      <jats:italic>kelch13,<\/jats:italic>\n                      which are collectively involved in resistance to six common anti-malarials. To compare frequency patterns over time,\n                      <jats:italic>P. falciparum<\/jats:italic>\n                      genotype data were also collated from studies published from across Angola in the last two decades.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      The two most important alleles for CQ resistance,\n                      <jats:italic>crt<\/jats:italic>\n                      76T and\n                      <jats:italic>mdr1<\/jats:italic>\n                      86Y, were found at respective frequencies of 71.4% and 6.5%. Historical data suggest that\n                      <jats:italic>mdr1<\/jats:italic>\n                      N86 has been steadily replacing 86Y throughout Angola in the last decade, while the frequency of\n                      <jats:italic>crt<\/jats:italic>\n                      76T has been more variable across studies. Over a third of new samples from Cabinda were \u2018quintuple mutants\u2019 for SP resistance in\n                      <jats:italic>dhfr<\/jats:italic>\n                      \/\n                      <jats:italic>dhps<\/jats:italic>\n                      , with a sixth mutation at\n                      <jats:italic>dhps<\/jats:italic>\n                      A581G present at 9.6% frequency. The markers\n                      <jats:italic>dhfr<\/jats:italic>\n                      51I,\n                      <jats:italic>dhfr<\/jats:italic>\n                      108N, and\n                      <jats:italic>dhps<\/jats:italic>\n                      437G have been nearly fixed in Angola since the early 2000s, whereas\n                      <jats:italic>dhfr<\/jats:italic>\n                      59R may have risen to high frequency more recently. Finally, no non-synonymous polymorphisms were detected in\n                      <jats:italic>kelch13<\/jats:italic>\n                      , which is involved in artemisinin resistance in Southeast Asia.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>\n                      Genetic markers of\n                      <jats:italic>P. falciparum<\/jats:italic>\n                      resistance to CQ are likely declining in frequency in Angola, consistent with the official discontinuation of CQ in 2006. The high frequency of multiple genetic markers of SP resistance is consistent with the continued public and private use of SP. In the future, more complete haplotype data from\n                      <jats:italic>mdr1<\/jats:italic>\n                      ,\n                      <jats:italic>dhfr<\/jats:italic>\n                      , and\n                      <jats:italic>dhps<\/jats:italic>\n                      will be critical for understanding the changing efficacy of multiple anti-malarial drugs. These data can be used to support effective drug policy decisions in Angola.\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.1186\/s12936-021-03713-2","type":"journal-article","created":{"date-parts":[[2021,4,7]],"date-time":"2021-04-07T09:06:05Z","timestamp":1617786365000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["Historical trends and new surveillance of Plasmodium falciparum drug resistance markers in Angola"],"prefix":"10.1186","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3244-4250","authenticated-orcid":false,"given":"Emily R.","family":"Ebel","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"F\u00e1tima","family":"Reis","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3664-9130","authenticated-orcid":false,"given":"Dmitri A.","family":"Petrov","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7004-3431","authenticated-orcid":false,"given":"Sandra","family":"Beleza","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2021,4,7]]},"reference":[{"key":"3713_CR1","doi-asserted-by":"publisher","first-page":"172","DOI":"10.4997\/JRCPE.2010.216","volume":"40","author":"A Butler","year":"2010","unstructured":"Butler A, Khan S, Ferguson E. 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