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The majority of commercial RDTs currently available detect the\n                      <jats:italic>Plasmodium falciparum<\/jats:italic>\n                      protein histidine-rich protein 2 (PfHRP2). There have also been recent reports of\n                      <jats:italic>pfhrp2<\/jats:italic>\n                      gene deletions being found in parasites collected from several African countries. The WHO has concluded that lacking the\n                      <jats:italic>pfhrp2<\/jats:italic>\n                      gene must be monitored in Africa. The purpose of the study was to analyse why the samples that were positive by PCR were negative by RDTs and, therefore, to determine whether there have been deletions in the\n                      <jats:italic>pfhrp2<\/jats:italic>\n                      and\/or\n                      <jats:italic>pfhrp3<\/jats:italic>\n                      genes.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      Malaria NM-PCR was carried out on all the samples collected in the field. A group of 128 samples was positive by PCR but negative by RDT; these samples were classified as RDT false-negatives. PCR was carried out for exon2 of\n                      <jats:italic>pfhrp2<\/jats:italic>\n                      and\n                      <jats:italic>pfhrp3<\/jats:italic>\n                      genes to detect the presence or absence of these two genes. Frequencies with 95% confidence intervals (CIs) were used for prevalence estimates. Associations were assessed by the Chi square test or Fisher\u00b4s exact test. The level of significance was set at p\u2009\u2264\u20090.05. Statistical analyses were performed using the software package SPSSv.15.0.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      After PCR, 81 samples were identified (4.7%, 95% CI 3.8\u20135.8) which had deletion in both genes,\n                      <jats:italic>pfhrp2<\/jats:italic>\n                      and\n                      <jats:italic>pfhrp3<\/jats:italic>\n                      . Overall, however, 11 samples (0.6%, 95% CI 0.36\u20131.14) had deletion only in\n                      <jats:italic>pfhrp2<\/jats:italic>\n                      but not in\n                      <jats:italic>pfhrp3<\/jats:italic>\n                      , and 15 (0.9%, 95% CI 0.6\u20131.5) presented with deletion only in\n                      <jats:italic>pfhrp3<\/jats:italic>\n                      but not in\n                      <jats:italic>pfhrp2<\/jats:italic>\n                      . Considering the\n                      <jats:italic>pfhrp2<\/jats:italic>\n                      gene separately, within the total of 1724 samples, 92 (5.3%, 95% CI 4.37\u20136.5) had evidence of deletion.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>\n                      The present study provides the first evidence of deletion in the\n                      <jats:italic>pfhrp2<\/jats:italic>\n                      and\n                      <jats:italic>pfhrp3<\/jats:italic>\n                      genes in\n                      <jats:italic>P. falciparum<\/jats:italic>\n                      isolates from Equatorial Guinea. However, larger studies across different regions within the country and across different seasonal profiles are needed to determine the full extent of\n                      <jats:italic>pfhrp2<\/jats:italic>\n                      and\n                      <jats:italic>pfhrp3<\/jats:italic>\n                      deletion. It is strongly recommended to implement an active surveillance programme in order to detect any increases in\n                      <jats:italic>pfhrp2<\/jats:italic>\n                      and\n                      <jats:italic>pfhrp3<\/jats:italic>\n                      deletion frequencies.\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.1186\/s12936-020-03178-9","type":"journal-article","created":{"date-parts":[[2020,3,2]],"date-time":"2020-03-02T07:02:32Z","timestamp":1583132552000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":43,"title":["First evidence of the deletion in the pfhrp2 and pfhrp3 genes in Plasmodium falciparum from Equatorial Guinea"],"prefix":"10.1186","volume":"19","author":[{"given":"Pedro","family":"Berzosa","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vicenta","family":"Gonz\u00e1lez","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Laura","family":"Taravillo","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alfredo","family":"Mayor","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mar\u00eda","family":"Romay-Barja","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luz","family":"Garc\u00eda","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Policarpo","family":"Ncogo","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Matilde","family":"Riloha","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Agust\u00edn","family":"Benito","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2020,3,2]]},"reference":[{"key":"3178_CR1","first-page":"266","volume":"35","author":"A Benito","year":"1994","unstructured":"Benito A, Roche J, Molina R, Amela C, Alvar J. 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Written informed consent for participation in the study was obtained from the caregivers interviewed and from the heads of the households.","order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethics approval and consent to participate"}},{"value":"Not applicable.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent for publication"}},{"value":"The authors declare that they have no competing interests.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}],"article-number":"99"}}