96T

serum

Human

The Dengue Early ELISA is a dengue NS1 antigen capture ELISA. It is for the qualitative detection of NS1 antigen in serum, used as an aid in the clinical laboratory diagnosis of patients with clinical symptoms consistent with dengue fever. The Dengue Early ELISA should be used in conjunction with other dengue serology.

1. Anti-NS1 Antibody Coated Microwells
2. HRP Conjugated Anti-NS1 MAb
3. Wash Buffer Concentrate
4. Serum Diluent 3
5. Tetramethylbenzidine TMB
6. Positive Control
7. Calibrator
8. Negative Control
9. Stop Solution

Store the kit at 4°C upon receipt. For more detailed information, please download the following document on our website.

Two hundred and fifty six (256) retrospective sera from individuals of various ages and both genders were tested on the Dengue Early ELISA as part of an in-house study. The sera included samples from the following groups: 69 endemic negative specimens from Thailand, 144 non-endemic negative specimens from Australia and the USA and 43 positive specimens from patients in Honduras and Thailand with early dengue infection. These samples were masked and tested on Dengue Early ELISA. The results were compared as the positive and negative agreement to a commercially available dengue NS1 antigen detection assay.The data is summarised in Table 1.
Table 1 Sensitivity and Specificity of Dengue Early ELISA

95% CI*
Patients with early dengue infections
Positive Presumptive
Agreement = 39/43 = 90.7% 77.9-97.4%
Normal Patients (Endemic and Non-Endemic)
Negative Presumptive
Agreementb = 212/212 = 100.0% 98.3-100.0%
Total Agreement = 251/255 = 98.4% 96.0-99.6%
*Confidence Interval.
a Retesting of equivocal sample was not conducted.
b Equivocal not included as retesting was not conducted.
CROSS-REACTIVITY
A panel of 95 specimens from patients with confirmed diseases other than dengue was tested to establish the analytical specificity of the Dengue Early ELISA. The specimens were from patients with diseases that have potential for crossreactivity. Each of the specimens included in the study was characterised with respect to disease diagnosis prior to analysis with the Dengue Early ELISA. Minimal crossreactivity was observed across 95 specimens. Refer to Table 3 for a summary of results.

Dengue virus is a flavivirus found largely in areas of the tropics and sub-tropics. Over half the world's population lives in regions at risk of potential dengue transmission, making dengue the most important arboviral disease in humans, in terms of morbidity and mortality. There are four distinct but antigenically related serotypes of dengue viruses, and transmission is by mosquito, principally Aedes aegypti, Aedes polynesienses and Aedes albopictus.
The clinical manifestations ofranging from sub-clinical through to fatal. The disease is graded dengue virus infection are varied, according to severity as follows: non-specific febrile illness, classic dengue fever, dengue haemorrhagic fever (DHF) (grades I and II), and dengue shock syndrome (DSS) (grades III and IV). Classic dengue fever is characterised by the sudden onset of fever with two or more symptoms of: headache, retro-orbital pain, myalgia, arthralgia, rash, haemorrhagic manifestations or leukopenia. A diphasic febrile course is common as is insomnia and anorexia with loss of taste or bitter taste. DHF and DSS are severe, potentially fatal complications often associated with infection by a second serotype.
Detection of dengue NS1 antigen by ELISA is a valuable procedure, as it allows detection of infection prior to seroconversion. NS1 antigen can be detected in serum from day 1 after onset of fever and up to day 9. This compares to IgM antibodies that are not detectable until days 3-5. Earlier diagnosis of dengue allows earlier implementation of supportive therapy and monitoring. This reduces risk of complications such as dengue haemorrhagic fever or dengue shock syndrome, especially in countries where dengue is endemic.