**1. Introduction**

Despite the significant advancement in medical sciences, dengue remains a serious public health concern in more than 100 countries, precisely in tropical and subtropical parts of the world. Dengue has alarming situation in Southeast Asia, South America, and Africa. Approximately, half of the world's population living in dengue endemic area is at the risk of getting dengue infection. Evidence shows that every year about 390 million dengue infection appears worldwide, of which 100 million cases are found to be symptomatic and require medical attention [1–3].

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2019 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Clinical symptoms typically appear 4–7 days following the mosquito bite and may persist for 3–10 days. Clinical manifestation of dengue varies from asymptomatic to acute febrile illness with headache, vomiting, severe myalgia, rash, retro-orbital pain, and arthralgia [4–6]. Classically, dengue was categorized as dengue fever, dengue hemorrhagic fever, and dengue shock syndrome. Nevertheless, classification was revised by the WHO in 2009 and classified it as dengue with or without warning signs. This version of classification divides dengue into three clinical phases: febrile, critical, and recovery phases [7, 8]. In the febrile phase, patient develops high fever due to acute viremia, and this phase lasts for 2–7 days. Critical phase usually lasts for 2 days and is indicated by plasma leakage, hemorrhage, and low platelet number. If patients survive in critical phase, then they will recover from the disease at the third phase known as recovery/convalescent phase [9, 10].

novel diagnostic platforms emerged for the diagnostic of infectious disease such as biosensor, microfluidic, loop-mediated isothermal amplification (LAMP), and so on. These diagnostic platforms were also explored by the researchers for developing a point-of-care test for the diagnosis of dengue. The below section will briefly give an insight into some of these plat-

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The criteria of point-of-care test resulted attractive for industry and researchers in order to develop and satisfy the qualification of ideal diagnostic test. Therefore, numerous researchers around the world have been working on biosensors in a search of potential point-of-care test as they offer several advantages such as high sensitivity and specificity, simple instrumentation, rapid assay outcome, portability and disposability of developed tools. Several researchers have reported biosensor for the diagnosis of dengue. In this section, we take a glance over current biosensor methods aimed to improve the diagnostic of dengue using different

Omar et al. reported an electrochemical immunosensor based on screen-printed carbon electrodes (SPCE) for the detection of dengue NS1 antigen. Anti-NS1-capturing antibodies were immobilized on BSA-modified working electrode of SPCE. The detection was based on the measurement of electron transfer resistance before and after the NS1 binding. The study demonstrated that the immunosensor successfully detected NS1 antigen with a limit of detection (LOD) of 0.3 ng/mL and the linear range was 1–200 ng/mL [24]. Pirich et al. worked on piezoelectric immunosensor to detect dengue NS1 antigen. For the enhanced binding of anti-NS1 antibodies, sensor surface was coated with a thin film of bacterial cellulose nanocrystals. The formation of antigen antibody complex was then analyzed using quartz crystal microbalance. The study showed that immunochip was able to detect dengue NS1 antigen from serum with a LOD of 0.32 μg/mL [25]. In another study, NS1 was detected using Langmuir–Blodgett and gold nanoparticles (AuNP) composite as a biosensing surface. The anti-NS1 antibodies were immobilized on the biosensing surface and then the sample containing NS1 antigen was pipetted on it. Subsequently, the biorecognition event between anti-NS1 antibody and NS1 antigen was detected through electrochemical impedance spectroscopy. The study showed that developed electrochemical immunosensor was capable to detect dengue with a LOD of

Jahanshahi et al. targeted the dengue IgM antibody as an analyte in an optical biosensor. In the assay, four serotypes of DENV were used as ligands for capturing IgM antibodies. The assay time of optical biosensor was just 10 minutes and required a minimum volume of 1 μl of sample to perform it. The sensitivity of developed sensor was ranging from 83 to 93% and specificity was 100% [27]. Ortega et al. reported a novel "Magnetic Paper-Based ELISA" for

forms investigated for the diagnosis of dengue.

*2.1.1. Biosensor platform*

*2.1.1.1. NS1 antigen detection*

1.19 ng/mL in spiked serum sample [26].

*2.1.1.2. Detection of dengue IgM antibodies*

biomarkers.

The spherical and enveloped dengue virus (DENV) which belongs to the family *Flaviviridae* is the causative agent of dengue. This virus is 50 nm in diameter and contains about 11 kb positive-sense single-stranded RNA genome that codes for three structural proteins (capsid, membrane, and envelope) and seven nonstructural proteins [11, 12]. The DENV is transmitted to human by the bite of *Aedes aegypti* and *Aedes albopictus* mosquito which usually breed in the clean water in urban areas [13, 14]. Each serotype of DENV can cause dengue and trigger inimitable immune response in host which provides long-term immunity to that particular serotype but limited and partial immunity against three other serotypes [15, 16]. Although, the four DENV serotypes are antigenically different but genetically are identical as they share about 65% of their RNA sequences [17, 18].
