Clinical assessment of NS1 antigen as an early serological marker in suspected cases of Dengue
Dr. Prem Prakash, Dr. Abhishek Kumar, Dr. SP Mahto
These serological tests detect either IgM and/or IgG antibodies or both. Antibody detection tests have low sensitivity for the early diagnosis because even the IgM antibodies start appearing after the 5th day of fever which delays the diagnosis and increases the mortality. Diagnosis of infection during the first week of fever is extremely important in the clinical management of the patient and to prevent potential outbreaks. In order to do so, antigen detection tests came to existence which detect NS1 antigen. This antigen is a non-structural protein which is a highly conserved protein which can be detectable during the very early phase of the disease. The levels of NS1 antigen in the circulation is very high in the acute phase of the disease and can be detected as early as day 1 of the fever. NS1 antigen is also highly specific in the diagnosis of dengue infection. Hence based on above background the present study was planned to know the clinical assessment of NS1 antigen as an early serological marker in suspected cases of dengue. The present study was planned in Department of Microbiology, ANMMC Gaya, Bihar from July 2018 to march 2019. Total 50 cases identified with symptoms of the dengue were enrolled in the present study. The cases were analysed for dengue serological markers. All the serum samples were screened for NS1 antigen and IgG and IgM antibodies by using lateral flow immunochromatographic rapid test. Platelet counts were detected by automated analyzer and duration of fever has been noted down. In India the problem of dengue is complex due to the large population, poor medical and diagnostic facilities and inadequate mosquito control. This country needs a quick effective technique and reliable diagnosis in addressing this potentially fatal, epidemic prone infection and large number of virus laboratories to confirm it and alert the public to take action. In conclusion, this study suggests that NS1 assays deserve inclusion in the diagnostic evaluation of dengue patients, but with due consideration for limitations in patients who present late in their illness or have a concomitant humoral immune response.