Clinical insights of H1N1 and H3N2 influenza viruses: A study from the Kalyana-Karnataka region

Background: Influenza viruses, particularly H1N1 and H3N2 variants, present significant public health challenges worldwide due to their potential to cause severe respiratory illnesses. Aim and Objective: To investigate the clinical characteristics, prevalence, and treatment outcomes of confirmed H1N1 and H3N2 infections in patients from multiple tertiary care hospitals in Kalyana, Karnataka, during August to October 2023. Materials and Methods: This study enrolled 11 patients with confirmed influenza infections. Demographic data, clinical presentations, underlying health conditions, treatment regimens, and outcomes were collected and analyzed. Results: The median age of patients was 48 years. Diabetes mellitus was the most prevalent risk factor, affecting 64% of the cohort. The predominant symptoms included fever with chills (81%), cough (63%), and respiratory distress. Laboratory tests confirmed 8 patients (72%) with H1N1 and 3 patients (27%) with H3N2. The majority of patients (82%) required ICU admission, with a mean length of stay of 4.5 days. Complications observed included septic shock, respiratory failure, and multiorgan dysfunction. One patient ultimately succumbed to the illness. Conclusion: This research highlights the critical need for vigilant monitoring and prompt treatment of influenza infections to reduce the risk of severe health complications. The findings emphasize the importance of public health measures and preparedness in managing seasonal influenza outbreaks, particularly in vulnerable populations.