ABSTRACT
Objective: To study the seasonal and demographic pattern of outbreak of dengue epidemic in Northern Pakistan during 2011. Patients and Methods: The study was conducted in the Virology department of Armed Forces institute of Pathology, Rawalpindi from 1st May to 31" December, 2011. This study included 2623 patients with critical suspicion of dengue fever. A venous blood sample of patients was drawn aseptically and tested for Dengue IgM antibodies by capture ELISA of Vircell, Spain. The test results obtained were positive, negative or equivocal. Those found equivocal an initial testing, were re-tested with fresh blood sample, after 3-4 days. I Results: The maximum number of the cases occurred during the months of September and October. 2011. Out of the total 2623 study subjects, 1923[73.3%] were males and 700[26.7%] were females. A total of 417[15.9%]patients tested positive for Dengue IgM antibodies out of which 318 [76.2%] were males and 99 [23.8%] were female, 28 [1%%] of patients. with equivocal results in initial testing for Dengue IgM were re-tested for the same tests after 3-4 days and 16 [57%] out of them confirmed positive or] repeat testing. Ages of patients ranged from 6 months to 90 years with a mean of 33.77 + 17.65 years. The maximum number of the positive cases was seen in the patients of age group of 76-30 years followed by 31-45 years. Conclusion: Dengue her epidemic was at its peak during Sep and Oct dung 2011. Itic psrtod 1rnmedi;rtcly atter the maximurn rains in the region. The dengue was diagnosed three limes more in male patients as corrlparerj tn temale patients. The dengue epidemic during 2011, affected people of all age groups and the most cases were diagnosed young adults followed by other age groups