Whereas after day 3 of illness, positivity of IgM antibody detection was found to be significantly higher compared to NS1 antigen detection ( P < 0.05). However, the difference was not found to be significant ( P = 0.180) which could be due to less number of sample size. The present study found virus isolation and RT-PCR as the most sensitive during first 3 days of illness, followed by NS1 antigen and IgM antibody detection. Among these, serological test for IgM antibody detection is most widely employed because of its wide availability, high sensitivity and specificity and also as the immunoglobulin are stable at tropical room temperature, specimen transport does not pose any problem.īecause of transient viremia and time required for antibody development, it is widely considered that dengue infection of <5 days illness may be diagnosed by virus isolation, viral nucleic acid detection and recently by viral NS1 antigen detection either by ELISA or rapid tests. Dengue cases are usually reported during post monsoon months as the climatic conditions during this period are considered favorable for breeding of Aedes aegypti mosquitoes.Ĭonfirmation of suspected dengue cases can be done by isolation of virus, viral RNA detection, viral antigen or IgM antibody detection in patients’ blood sample. The knowledge of seasonal trends is important for timely implementation of effective control and preventive measures. In several other studies pediatric population was most commonly affected. The higher positivity among young adult males (61%) is consistent with previous dengue reports by the authors, as well as other Indian studies. In our study 35.5% of cases were serologically positive for dengue infection. Early diagnosis of disease is of importance, as with timely intervention case fatality can be reduced to <1% in severe cases. To detect the sensitivity of NS1 antigen for different dengue virus serotypes four dengue serotype 1 and 12 dengue serotype 3 (2 from 2010 and 10 from 2008) were subjected for NS1 antigen detection.ĭengue is a disease with wide spectrum of clinical manifestations mimicking several other illnesses. The samples tested positive by any of the four mentioned tests were considered as positive for dengue viral infection and were included for analysis. Dengue IgM was performed by MAC ELISA (National Institute of Virology, Pune, India) and dengue NS1 antigen detected by NS1 by ELISA (Panbio, Australia) as per manufacturer's instructions. Samples collected within 5 days of illness were further subjected for viral RNA detection and virus isolation in C6/36 cell lines. One hundred and eleven samples were subjected to NS1 antigen ELISA whose information on duration of illness was available. All these samples were tested for dengue IgM antibody by MAC ELISA as a routine diagnostic service of the department. The inclusion criteria for dengue cases were considered as per the WHO criteria. of Virology, Postgraduate Institute of Medical Education and Research, Chandigarh, which is one of the apex centers for advanced diagnosis of dengue, Japanese encephalitis, chikungunya and other arboviral infections under National Vector Borne Disease Control Programme, Ministry of Health and Family Welfare.Ī total of 2101 blood sample were received from clinically suspected dengue cases from Chandigarh and neighboring states during 2010. Considering the above-mentioned kinetics, the present study compared the positivity of different tests during different phases of dengue viral illness in order to guide the microbiologists and clinicians to follow the appropriate diagnostic strategy. Thus, different diagnostic tests available for dengue viral infection testing are applicable at different phases of illness. Molecular techniques like RT-PCR, multiplex RT-PCR and real-time PCR system have also been reported for early detection of dengue RNA to warrant as acute dengue infection. As these tests are time consuming, requires paired samples and tedious to perform presently replaced with dengue IgM antibody detection by MAC ELISA and dengue NS1 antigen by ELISA tests. The hemagglutination inhibition (HI) and complement fixation test (CFT) were previously the recommended tests by World Health Organisation (WHO). Isolation of virus is confirmative but less sensitive and time consuming. Several diagnostic tests are presently available for diagnosis of dengue viral infection. A majority of patients suffer from self-limiting febrile illness (dengue fever DF), whereas some may progress to severe life-threatening dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). Dengue viral infection is caused by one of the dengue virus types (DENV 1-4) belonging to the family Flaviviridae.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |