Clinical and Epidemiological Characteristics of Seasonal Influenza Virus Infection in Hospitalized Patients in Mashhad, Iran, ۲۰۰۹-۲۰۱۷: A Retrospective Study

Abstract: Objective: Despite the availability of effective vaccines and antiviral treatments, influenza remains a significant cause of hospitalizations and mortality globally. This study aimed to evaluate the epidemiological characteristics, clinical manifestations, and outcomes of patients diagnosed with seasonal influenza in two referral centers in northeastern Iran. Methods: This retrospective cross-sectional study analyzed data from ۵۸ patients with a mean age of ۴۵ who tested positive for seasonal influenza via PCR. These patients were hospitalized at Imam Reza and Qaem hospitals between ۲۰۰۹ and ۲۰۱۷. Data were collected using a standardized checklist and analyzed using SPSS software version ۲۳. Non-normally distributed data were assessed using the Mann-Whitney test, while qualitative variables were compared using the Chi-square test, with Fisher's exact test applied when necessary. Results: Among the ۵۸ influenza-infected patients, ۳۷ (۶۷.۲%) survived, ۱۸ (۳۲.۷%) died, and ۶ (۱۰.۹%) were discharged at their own request. Influenza A subtypes identified included H۱N۱ (۱۵.۷%) and H۳N۲ (۲۳.۶%), with ۶۰.۵% remaining untyped. Antiviral drug administration did not significantly correlate with hospital mortality. However, initiating antiviral treatment within the first ۴۸ hours did influence mortality outcomes. Patient age, influenza virus type, and subtype showed no significant relationship with hospital mortality. Conclusion: The study highlights concerning clinical outcomes and hospital mortality rates among patients diagnosed with seasonal influenza. Given the preventable nature of influenza and the challenges in managing these patients, there is an urgent need to enhance physician awareness, particularly among specialists. Emphasizing timely diagnostic and therapeutic interventions is critical, especially during peak influenza seasons.

کلیدواژه ها:

Epidemiology ، Influenza ، Clinical outcome ، Socio-economic burden.