{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T12:23:23Z","timestamp":1785414203173,"version":"3.56.0"},"reference-count":26,"publisher":"Cambridge University Press (CUP)","license":[{"start":{"date-parts":[[2025,6,26]],"date-time":"2025-06-26T00:00:00Z","timestamp":1750896000000},"content-version":"unspecified","delay-in-days":176,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":["cambridge.org"],"crossmark-restriction":true},"short-container-title":["Epidemiol. Infect."],"published-print":{"date-parts":[[2025]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>The aim of this study was to describe how the detection of protozoan and helminth parasites has been affected by the introduction of polymerase chain reaction (PCR) and changes in test algorithms. We extracted data about faecal samples tested for parasites (n = 114839) at five Norwegian clinical microbiology laboratories. Samples were classified into prePCR or postPCR depending on whether they were submitted before or after the introduction of PCR, and into diagnostic episodes (n = 99320). The number of diagnostic episodes increased 3.7-fold from prePCR to postPCR. Giardia positive episodes doubled, the positivity rate decreased from 2.0% to 1.3%. Cryptosporidium was hardly detected prePCR and increased to a positivity rate of 1.2%. Entamoeba histolytica was rarely found. Episodes examined for helminths decreased 51%, the number of positive episodes decreased 34%. Samples from immigrants were more likely to be positive for Giardia, E. histolytica, or helminths and less likely to be Cryptosporidium positive. During the COVID-19 pandemic, the number of Giardia and helminth-positive episodes decreased. Cryptosporidium-positive episodes remained unchanged. The implementation of multiplex PCR for protozoa led to a doubling of Giardia cases and a better test for Cryptosporidium. Fewer microscopy examinations raise concerns that helminth infections may be overlooked.<\/jats:p>","DOI":"10.1017\/s0950268825100228","type":"journal-article","created":{"date-parts":[[2025,6,26]],"date-time":"2025-06-26T02:40:54Z","timestamp":1750905654000},"update-policy":"https:\/\/doi.org\/10.1017\/policypage","source":"Crossref","is-referenced-by-count":1,"title":["Transitioning from microscopy to PCR for protozoa in Norway \u2013 Impact on detection of protozoa and helminths: A register study"],"prefix":"10.1017","volume":"153","author":[{"ORCID":"https:\/\/orcid.org\/0009-0004-4029-8232","authenticated-orcid":false,"given":"Lars","family":"Sandven","sequence":"first","affiliation":[{"name":"F\u00f8rde Central hospital"},{"name":"Haukeland University Hospital"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hanne","family":"Brekke","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/00j9c2840","id-type":"ROR","asserted-by":"publisher"}],"name":"Oslo University Hospital Ullev\u00e5l"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tore","family":"Lier","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/030v5kp38","id-type":"ROR","asserted-by":"publisher"}],"name":"University Hospital of Northern Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Liv Reidun","family":"Tverelv","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/030v5kp38","id-type":"ROR","asserted-by":"publisher"}],"name":"University Hospital of Northern Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jan Egil","family":"Afset","sequence":"additional","affiliation":[{"name":"Norwegian University of Science and Technology"},{"id":[{"id":"https:\/\/ror.org\/01a4hbq44","id-type":"ROR","asserted-by":"publisher"}],"name":"St. Olavs Hospital, Trondheim University Hospital"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Audun","family":"Sivertsen","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/03np4e098","id-type":"ROR","asserted-by":"publisher"}],"name":"Haukeland University Hospital"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kurt","family":"Hanevik","sequence":"additional","affiliation":[{"name":"UiB"},{"id":[{"id":"https:\/\/ror.org\/03zga2b32","id-type":"ROR","asserted-by":"publisher"}],"name":"Haukeland University Hospital"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"56","published-online":{"date-parts":[[2025,6,26]]},"reference":[{"key":"S0950268825100228_r1","first-page":"pii=2300509","article-title":"Autochthonous and imported giardiasis cases: an analysis of two decades of national surveillance data, Germany, 2002 to 2021","volume":"29","author":"Hommes","year":"2024","journal-title":"Euro Surveillance"},{"key":"S0950268825100228_r16","first-page":"209","article-title":"The experimental transmission of human intestinal protozoan parasites. 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Giardia lamblia cysts given in capsules","volume":"59","author":"Rendtorff","year":"1954","journal-title":"The Americal Journal of Hygiene"},{"key":"S0950268825100228_r17","doi-asserted-by":"publisher","DOI":"10.1093\/cid\/ciaa128"},{"key":"S0950268825100228_r14","doi-asserted-by":"publisher","DOI":"10.1007\/s10096-015-2519-2"},{"key":"S0950268825100228_r12","doi-asserted-by":"publisher","DOI":"10.1016\/j.diagmicrobio.2015.11.005"},{"key":"S0950268825100228_r8","doi-asserted-by":"publisher","DOI":"10.2807\/1560-7917.ES2015.20.24.21160"},{"key":"S0950268825100228_r2","doi-asserted-by":"publisher","DOI":"10.2174\/1872213X13666190618124901"},{"key":"S0950268825100228_r26","doi-asserted-by":"publisher","DOI":"10.1046\/j.1440-1746.2000.02089.x"},{"key":"S0950268825100228_r21","first-page":"76","article-title":"The need for three stool specimens in routine laboratory examinations for intestinal parasites","volume":"47","author":"Nazer","year":"1993","journal-title":"British Journal Clinical Practice"},{"key":"S0950268825100228_r23","doi-asserted-by":"publisher","DOI":"10.1080\/22221751.2024.2412624"},{"key":"S0950268825100228_r22","doi-asserted-by":"publisher","DOI":"10.1056\/NEJM199407213310304"},{"key":"S0950268825100228_r13","doi-asserted-by":"publisher","DOI":"10.1016\/S0890-8508(03)00057-4"},{"key":"S0950268825100228_r15","doi-asserted-by":"publisher","DOI":"10.1128\/JCM.36.4.995-998.1998"},{"key":"S0950268825100228_r11","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pntd.0006892"},{"key":"S0950268825100228_r4","doi-asserted-by":"publisher","DOI":"10.1128\/CMR.15.1.145-154.2002"},{"key":"S0950268825100228_r20","doi-asserted-by":"crossref","first-page":"869","DOI":"10.1111\/j.1469-0691.2009.02894.x","article-title":"Parasitological diagnosis combining an internally controlled real-time PCR assay for the detection of four protozoa in stool samples with a testing algorithm for microscopy","volume":"15","author":"Wallinga","year":"2009","journal-title":"Clinical Microbiology and Infection"},{"key":"S0950268825100228_r3","doi-asserted-by":"publisher","DOI":"10.1007\/s10096-020-03974-w"},{"key":"S0950268825100228_r19","doi-asserted-by":"publisher","DOI":"10.4269\/ajtmh.1995.53.36"},{"key":"S0950268825100228_r18","doi-asserted-by":"publisher","DOI":"10.1186\/1471-2458-10-41"},{"key":"S0950268825100228_r9","doi-asserted-by":"publisher","DOI":"10.1093\/cid\/ciu629"},{"key":"S0950268825100228_r6","doi-asserted-by":"publisher","DOI":"10.1186\/1471-2458-6-141"},{"key":"S0950268825100228_r5","unstructured":"[5] Meldingssystem for smitsomme sykdommer, Norge (MSIS). https:\/\/statistikk.fhi.no\/msis\/sykdomshendelser?etter=diagnose&fordeltPaa=aar&diagnose=305,309&diagramtype=tabell&tidsrom=2014,2021."},{"key":"S0950268825100228_r10","doi-asserted-by":"publisher","DOI":"10.1007\/s00436-022-07524-5"},{"key":"S0950268825100228_r25","doi-asserted-by":"publisher","DOI":"10.1128\/spectrum.02741-21"},{"key":"S0950268825100228_r24","first-page":"100060","article-title":"The incidence of infectious diseases and viruses other than SARS-CoV-2 amongst hospitalised children in Oslo, Norway during the Covid-19 pandemic 2020-2021","volume":"2","author":"Knudsen","year":"2022","journal-title":"Journal of Clinical Virol Plus"},{"key":"S0950268825100228_r7","doi-asserted-by":"publisher","DOI":"10.3201\/eid2004.121415"}],"container-title":["Epidemiology and Infection"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.cambridge.org\/core\/services\/aop-cambridge-core\/content\/view\/S0950268825100228","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,7]],"date-time":"2025-10-07T15:56:06Z","timestamp":1759852566000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.cambridge.org\/core\/product\/identifier\/S0950268825100228\/type\/journal_article"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025]]},"references-count":26,"alternative-id":["S0950268825100228"],"URL":"https:\/\/doi.org\/10.1017\/s0950268825100228","relation":{},"ISSN":["0950-2688","1469-4409"],"issn-type":[{"value":"0950-2688","type":"print"},{"value":"1469-4409","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025]]},"assertion":[{"value":"\u00a9 The Author(s), 2025. Published by Cambridge University Press","name":"copyright","label":"Copyright","group":{"name":"copyright_and_licensing","label":"Copyright and Licensing"}},{"value":"This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http:\/\/creativecommons.org\/licenses\/by\/4.0), which permits unrestricted re-use, distribution and reproduction, provided the original article is properly cited.","name":"license","label":"License","group":{"name":"copyright_and_licensing","label":"Copyright and Licensing"}},{"value":"This content has been made available to all.","name":"free","label":"Free to read"}],"article-number":"e80"}}