The Government of Delhi on 23 Sept 2013 advised all the city hospitals to rely only on the ELISA (Enzyme-Linked Immune Sorbent Assay) Test for confirmation of dengue, in order to put an end on any kind of confusion. The doctors explained that any person arriving in the hospital within 5-6 days of seeing dengue symptoms, should be tested for antigens’ presence for confirmation of dengue. In case a person arrives after a week, then there should be the test of presence of the antibodies against the virus. In both the cases, ELISA test should be performed.
Without the proper guidelines, various city hospitals in Delhi conducted the cheaper Rapid Diagnostic Kits (RDKs). However, Rapid Diagnostic Kits (RDKs) gave improper and false results. As per the guidelines of the Delhi Government, the tests carried out by RDKs will remain invalid. The cost of ELISA Test is 2000-2500 Rupees in comparison to 1000-1500 Rupees for RDKs.
The Municipal Authorities in Delhi explained that the antibody test reports will remain valid only if they have been done using the ELISA Test. According to the World Health Organization’s guidelines, IgG and IgM are the two antibodies which are produced against virus and these two should be considered as test for checking the dengue virus. The municipal health officer of the South Corporation, Dr N K Yadav explained that only ELISA-based tests will be considered valid and will be accepted.
About the ELISA Test
• ELISA stands for enzyme-linked immune sorbent assay.
• Dengue is detectable by isolation of the virus through serological tests or molecular methods.
• Diagnosis of the on-going or recent dengue infection can be confirmed by checking the serum samples during first 5 days or early convalescent phase (i.e., more than 5 days) of dengue symptoms.
• IgM antibody capture ELISA (MAC-ELISA) format is widely used in various diagnostic laboratories as well as diagnostic kits. Apart from this, IgG ELISA, which is used for detection of past dengue infection makes use of same viral antigens like the MAC ELISA.