Dengue Infection - Seroprevalence and Seasonal Variation among patients attending a Tertiary Care Hospital at Visakhapatnam, Andhra Pradesh, India

Abstract

Introduction: Dengue infections have become a considerable threat to public health systems in developing countries. This study determines seroprevalence of dengue virus, seropositivity of Dengue NS1 antigen, IgM and IgG antibodies, Seasonal variation of dengue infection, and demographic profile of dengue-positive patients. Methods: A retrospective study was conducted at the Microbiology Department of Gayatri Vidya Parishad Institute of Health Care and Medical Technology, Visakhapatnam, India, from January 2018 to December 2019. A total of 5554 samples were collected from patients who were suspected of suffering from Dengue fever in the Medicine and Paediatrics wards. The patients were checked using Dengue Duo rapid test method from a commercial supply for combined Dengue NS1 antigen, IgM, and IgG antibody detection. Results: A total of 5554 serum samples were analyzed, among which 1045 were Dengue positive. The seroprevalence of dengue was 21.13% (95% confidence intervals (CI) 19.8– 22.6%) in 2018 and 15.40% (95% CI 13.9– 16.9%) in 2019. NS1 was positive in 835 (79.9%), IgM was positive in 26 (2.48%), IgG was positive in 116 (11.10%), and 68 were positive with both antigens and both antibodies. An outbreak occurred from July to October, indicating increased vector transmission in the monsoon and post-monsoon periods. Conclusion: The present study confirms that Dengue is mainly a disease of the rainy season, and effective implementation of vector control measures through efforts toward vector breeding source reduction and using personal prophylactic measures against mosquito bites will help in reducing the dengue prevalence in the community.