- healthy healthcare workers' refusal. - pregnancy and lactation. - confirmed acute cases of sars-cov-2 infection - having a history of sars-cov-2 infection in the past 3 months. - fever (body temperature > 37.0 ℃), dry cough, fatigue, nasal obstruction, runny nose, pharyngeal pain, myalgia, diarrhea, shortness of breath and dyspnea occurred within 14 days before vaccination. - history of allergy to any vaccines - previous vaccination within the last 30 days

- healthy healthcare workers' refusal. - pregnancy and lactation. - confirmed acute cases of sars-cov-2 infection - having a history of sars-cov-2 infection in the past 3 months. - fever (body temperature > 37.0 ℃), dry cough, fatigue, nasal obstruction, runny nose, pharyngeal pain, myalgia, diarrhea, shortness of breath and dyspnea occurred within 14 days before vaccination. - history of allergy to any vaccines - previous vaccination within the last 30 days

- healthy healthcare workers' refusal. - pregnancy and lactation. - confirmed acute cases of sars-cov-2 infection - having a history of sars-cov-2 infection in the past 3 months. - fever (body temperature > 37.0 ℃), dry cough, fatigue, nasal obstruction, runny nose, pharyngeal pain, myalgia, diarrhea, shortness of breath and dyspnea occurred within 14 days before vaccination. - history of allergy to any vaccines - previous vaccination within the last 30 days - immunodeficiency, autoimmune disorders, receiving immunosuppressive therapy or presence of chronic illness.

- healthy healthcare workers' refusal. - pregnancy and lactation. - confirmed acute cases of sars-cov-2 infection - having a history of sars-cov-2 infection in the past 3 months. - fever (body temperature > 37.0 ℃), dry cough, fatigue, nasal obstruction, runny nose, pharyngeal pain, myalgia, diarrhea, shortness of breath and dyspnea occurred within 14 days before vaccination. - history of allergy to any vaccines - previous vaccination within the last 30 days - immunodeficiency, autoimmune disorders, receiving immunosuppressive therapy or presence of chronic illness.