High Prevalence of Influenza A (H1N1 and H3N2) Infection in South Iran

Background: Influenza A is divided into a number of subtypes, the most common of which are circulating H3N2 and H1N1. Influenza A and B viruses, which normally circulate in humans (human influenza viruses), are responsible for seasonal influenza pandemics each year. This study evaluated the prevalence of influenza in Hormozgan province and determined the type and subtypes of influenza circulating in the community. Materials and Methods: The present study was conducted in a single center on 1237 patients with acute respiratory syndrome and flu-like symptoms in Hormozgan province, Iran from August 2022 to December 2022. Eventually, patients’ data such as the age, gender, and hospitalization rate of patients with influenza underwent investigation. Results: Out of a total of 1237 samples of patients, 349 (28.2%) cases were diagnosed with positive influenza and 888 (71.80%) cases were negative. Of 349 cases of positive influenza, 3 and 346 cases were diagnosed with influenza B and A, respectively. The results represented that out of a total of 349 positive cases of influenza, 216 (61.90%) and 133 (38.10%) people were hospitalized and visited as outpatients, respectively. Conclusion: From August 2022 to December 2022, Hormozgan province in the south of Iran witnessed an influenza peak with an increase in the prevalence of H1N1 and H3N2 subtypes. The dominant subtype of this peak was H3N2 influenza, but the prevalence of the H1N1 subtype also demonstrated a significant increase. Finally, the cases of hospitalization of patients with positive influenza represented an increase.