title: Observation on dengue cases from a virus diagnostic laboratory of a tertiary care hospital in North India.
abstract: OBJECTIVE
  The epidemiology of dengue fever (DF) is complex in the Indian subcontinent as all the four serotypes are circulating. This study reports observations on dengue cases from a virus diagnostic laboratory of a north Indian tertiary care hospital catering to areas in and around Lucknow, Uttar Pradesh.
  
  
  METHODS
  Serum samples were obtained from suspected cases of dengue referred to the virus diagnostic laboratory during 2011 to 2013, and detailed history was taken on a pre-structured datasheet. All samples were tested for anti-dengue virus (DV) IgM antibodies and DV-non structural protein 1 antigen (NS1Ag) by ELISA. NS1Ag positive samples were tested further by conventional RT-PCR for DV-RNA detection and serotyping.
  
  
  RESULTS
  Of the 4019 suspected patients of dengue, 886 (22%) showed laboratory evidence of dengue virus infection. Of these, 19, 17 and 27 per cent were positive in 2011, 2012 and 2013, respectively. Children and adults were similarly affected by dengue in all the three years. Males were more commonly affected than females. The predominant DV serotype detected was DV-2, DV-1 and DV-3 in 2011, 2012 and 2013, respectively. DV-4 serotype was not detected. About half the cases positive for DV infection, showed symptoms of dengue with warning signs/ severe dengue. A distinct seasonality with increase in number of dengue cases in the post monsoon period was seen.
  
  
  CONCLUSIONS
  Change in circulating serotype of dengue virus; a distinct adult dengue involvement; and a remarkable number of cases presenting with severe dengue manifestations are the main findings of this study.
authors.forename: Om
authors.initials: O
authors.lastname: Prakash
authors.forename: Desh Deepak
authors.initials: DD
authors.lastname: Singh
authors.forename: Geetika
authors.initials: G
authors.lastname: Mishra
authors.forename: Shantanu
authors.initials: S
authors.lastname: Prakash
authors.forename: Arvind
authors.initials: A
authors.lastname: Singh
authors.forename: Shikha
authors.initials: S
authors.lastname: Gupta
authors.forename: Jasmeet
authors.initials: J
authors.lastname: Singh
authors.forename: Danish Nasar
authors.initials: DN
authors.lastname: Khan
authors.forename: Parul
authors.initials: P
authors.lastname: Jain
authors.forename: Anamika
authors.initials: A
authors.lastname: Vishal
authors.forename: Manoj Kumar
authors.initials: MK
authors.lastname: Pandey
authors.affiliation: Department of Microbiology, King George's Medical University, Lucknow, India.
authors.forename: Amita
authors.initials: A
authors.lastname: Jain
mesh_terms: D000293:Adolescent; D000328:Adult; D000914:Antibodies, Viral / Q000097:blood* / Q000276:immunology; D002648:Child; D002675:Child, Preschool; D003715:Dengue / Q000097:blood / Q000453:epidemiology* / Q000821:virology; D003716:Dengue Virus / Q000276:immunology / Q000302:isolation & purification* / Q000472:pathogenicity; D005260:Female; D006801:Humans; D007075:Immunoglobulin M / Q000097:blood* / Q000276:immunology; D007194:India; D008297:Male; D012621:Seasons; D012703:Serotyping
chemical_list: D000914:Antibodies, Viral; D007075:Immunoglobulin M