Editing Dengue fever (section)

== Diagnosis ==
Mild cases of dengue fever can easily be confused with several common diseases including [[Influenza]], [[measles]], [[chikungunya]], and [[Zika fever|zika]].<ref name="WHO-2009">{{Cite book |date=21 April 2009 |title=Dengue guidelines, for diagnosis, treatment, prevention and control |url=https://www.who.int/publications-detail-redirect/9789241547871 |access-date=2024-03-07 |page=46 |language=en |isbn=978-92-4-154787-1 |quote=Textbox B and Textbox C. |publisher=World Health Organization |vauthors=Organization WH |archive-date=16 March 2024 |archive-url=https://web.archive.org/web/20240316010639/https://www.who.int/publications/i/item/9789241547871 |url-status=live }}</ref><ref name="MSD Manual Professional Edition">{{Cite web |title=Dengue - Infectious Diseases |url=https://www.msdmanuals.com/en-gb/professional/infectious-diseases/arboviruses,-arenaviridae,-and-filoviridae/dengue |access-date=2024-03-04 |website=MSD Manual Professional Edition |language=en-GB |archive-date=4 March 2024 |archive-url=https://web.archive.org/web/20240304203003/https://www.msdmanuals.com/en-gb/professional/infectious-diseases/arboviruses,-arenaviridae,-and-filoviridae/dengue |url-status=live }}</ref> Dengue, chikungunya and zika share the same mode of transmission (''Aedes'' mosquitoes) and are often endemic in the same regions, so that it is possible to be [[Coinfection|infected simultaneously]] by more than one disease.<ref name="Beltran-Silva-2018" /> For travellers, dengue fever diagnosis should be considered in anyone who develops a fever within two weeks of being in the [[tropics]] or [[subtropics]].<ref name="NEJM2012" />

[[File:Dengue testing.png|thumb|upright=1.5|Graph of when laboratory tests for dengue fever become positive. Day zero refers to the start of symptoms, 1st refers to in those with a primary infection, and 2nd refers to in those with a secondary infection.<ref name="NEJM2012" />]]

Warning symptoms of severe dengue include abdominal pain, persistent vomiting, odema, bleeding, lethargy, and liver enlargement. Once again, these symptoms can be confused with other diseases such as malaria, gastroenteritis, leptospirosis, and typhus.<ref name="WHO-2009"/>

Blood tests can be used to confirm a diagnosis of dengue. During the first few days of infection, enzyme-linked immunosorbent assay ([[ELISA]]) can be used to detect the [[NS1 antigen test|NS1 antigen]]; however this antigen is produced by all flaviviruses.<ref name="Beltran-Silva-2018">{{Cite journal | vauthors = Beltrán-Silva SL, Chacón-Hernández SS, Moreno-Palacios E, Pereyra-Molina JÁ |date=2018-07-01 |title=Clinical and differential diagnosis: Dengue, chikungunya and Zika |url=https://www.elsevier.es/en-revista-revista-medica-del-hospital-general-325-articulo-clinical-differential-diagnosis-dengue-chikungunya-S0185106316301135 |journal=Revista Médica del Hospital General de México |language=en |volume=81 |issue=3 |pages=146–153 |doi=10.1016/j.hgmx.2016.09.011 |issn=0185-1063 |access-date=7 March 2024 |archive-date=4 March 2024 |archive-url=https://web.archive.org/web/20240304213207/https://www.elsevier.es/en-revista-revista-medica-del-hospital-general-325-articulo-clinical-differential-diagnosis-dengue-chikungunya-S0185106316301135 |url-status=live |doi-access=free }}</ref><ref name=":5"/> Four or five days into the infection, it is possible to reliably detect anti-dengue [[IgM]] antibodies, but this does not determine the serotype.<ref name="Beltran-Silva-2018"/> [[Nucleic acid test|Nucleic acid amplification tests]] provide the most reliable method of diagnosis.<ref name=":5" />