Dengue is endemic in Kolkata, India. Outbreaks of dengue cases often occur regularly at short intervals. This
retrospective seroepidemiological surveillance was conducted longitudinally. Dengue cases were diagnosed
in the laboratories from suspected patients by dengue specific IgG, IgM antibodies and NS1 antigen, from
suspected persons to investigate, analyze and categorize the cases who were actually suffering from dengue to
diagnose a dengue patient in the laboratory practice along with the status of the patient related to the detection
of disease and duration of primary and secondary infection for effective monitoring of the patient. Age and
Sex of the dengue patients were determined. Detection of dengue in unsuspected fever cases in unfavorable
transmission season was evaluated. The transmission of dengue infection in the non-transmission season is
not remarkable and often remains submerged. Proper measure at this stage may prevent the epidemic
outbreak in the transmission season. This sort of experience will help to enrich the effective control and case
management of the menace.