Hemoglobin changes in Covid-19 patients with and without a history of influenza vaccination

Background: Although the COVID-19 pandemic has subsided, its significance remains due to its 2–14 day incubation period, symptom similarity with the common cold, and high transmission ability, as well as its consequences and complications. This study aimed to compare the clinical and laboratory findings in COVID-19 patients with and without a history of influenza vaccination. Methods: This study was a comparative analytical study. A total of 60 hospitalized patients from Ferdows Hospital and Behlool Gonabad Hospital were selected based on inclusion criteria and a convenience sampling method. Data collection involved demographic information, clinical symptom forms, and laboratory test results. Data analysis was performed using SPSS version 18. Results: Findings showed that COVID-19 patients with a history of influenza vaccination had less severe clinical symptoms, with fewer individuals experiencing severe symptoms. However, this difference was not statistically significant. A statistically significant difference (P = .020) was found between the two groups regarding hemoglobin changes, with a greater decrease in hemoglobin levels observed in the unvaccinated group. Comparison of CRP, WBC, and platelet counts between the two groups revealed no statistically significant differences (P > .05). Conclusions: The results of this study suggest that a history of influenza vaccination influences changes in hemoglobin levels in COVID-19 patients. Given that COVID-19 vaccination is not universally accepted and there is no mandatory vaccination policy, and considering the established impact of reduced hemoglobin levels on the severity and outcomes of COVID-19, influenza vaccination is recommended to prevent complications.