Evaluation of the Possible Effect of the Influenza Vaccine on the Severity, Mortality, and Length of Hospitalization among Unvaccinated COVID-19 Patients; An Observational, Cross-Sectional Study - Alizadeh, Nafiseh; Tabatabaei, Fatemeh Sadat; Borran, Mina; Dianatkhah, Mehrnoush; Azimi, Amirali; Forghani, Seyedeh Nafise; Akbarpour, Samaneh; Alizadeh, Mahboubeh; Torabi, Sara; Faraji, Neda (Journal of Pharmaceutical Care, 2022)