This is a retrospective observational study aimed to search the alteration of circulating dengue virus (DENV) serotypes in Dhaka City for five consecutive years (2017-2021) along with disease outcome. Methods: Routine dengue NS1 or PCR positive dengue samples from patients who visited Evercare Hospital Dhaka (ex. Apollo Hospitals Dhaka) were selected for serotype determination by serotype specific real time reverse transcriptase PCR (RT-PCR). Results: In 2017, predominant serotype was DENV-2 (91.3%) with less than 5% of DENV-1 and DENV-3 among 161 cases. In 2018, among127 cases, DENV-2 was the predominant serotype (40.95%) followed by DENV-3 (33.07%) and DENV-1 (25.98%). In 2019, predominance of DENV-2 was totally replaced by DENV-3 (91.86%) and DENV-1 (8.14%). In 2021, only DENV-3 serotype was detected among 178 samples. Regarding serotype association with disease outcome, more severe cases (Dengue Hemorrhagic Fever/Dengue Shock Syndrome) were observed from 2019 with notable shifting of serotype dominance to DENV-3 from DENV-2 in previous years. In our cohort, the prevailing age group was 1-20 years which is analogous with many studies in Asia. Conclusion: Dominance of DENV serotype shifted to DENV-3 in 2019 from prolonged persistence of DENV-2 and DENV-1. Continuous surveillance for circulating DENV serotype is needed for preparedness of potential outbreaks and occurrence of severe cases. Bangladesh J Med Microbiol 2021; 15 (2): 23-29

Dengue virus is the most important mosquito-borne viral disease in the world. Co-circulation of the four types of dengue viruses and expansion of dengue epidemic give rise to infection enhancement and a big expansion of clinical aspects of the disease. Besides dengue, typhoid fever is an ancient disease, have emerged as major public health problem in developing countries including Bangladesh. Here we report a case of 4 years old boy, who have developed Dengue Hemorrhagic Fever within 2 weeks of contemporaneous infection of Typhoid fever and Primary dengue fever. Anwer Khan Modern Medical College Journal Vol. 11, No. 1: Jan 2020, P 78-81