**7. Diagnosis of dengue fever**

Dengue infection symptoms are the major tool for its diagnosis. However, this is not a reliable method for the confirmation of dengue infection but laboratory studies are needed [42, 43]. Dengue virus in the initial stages may cause fever to dengue fever or later on more it can result in severe dengue. Common tools for the detection of dengue infection in laboratory tests include; an identification of the particular viral serotype, genomic sequences, viral antigen, genomic sequence, and/or antibodies. Major advances in the diagnosis of this infection include IgM captured ELISA, dengue specific monoclonal antibodies, viral RNA detection by nucleic acid amplification tests (NAAT), and viral isolation from mosquito cell lines and also live mosquitoes, all these are reported to have major advances in dengue diagnosis. Diagnosis involves two levels of detection. At level one, the patient is in acute febrile phase, where NS1 antigens and viral RNA can be detected, and at level two is the stage in which IgG and IgM antibodies are abundant in blood with the post febrile period [44]. Acute stages of dengue may be represented by flu like fever in which diagnosis is made possible by identifying viral RNA/proteins in the patient's blood. Dengue viral RNA can also be identified in early stage of infection using RT-PCR. This technique is quite reliable but unaffordable for the poor people [45, 46]. ELISA test is also being utilized to identify primary as well as secondary infection by utilizing dengue-specific monoclonal NS1 antibody to identify NS1 in victim's blood [47–49]. MACELISA assays in combination with NS1 Ag can be utilized for the detection of dengue viruses in earlier stages of infection [50]. Commonly used laboratory methods include immune-fluorescence tests, capture ELISAs, and hemagglutination assays [51]. Nonetheless, it is important to consider that serological tests can be misleading due to cross-reactivity while there is more that flavivirus circulating in the region.
