lungs pneumonia logo . human lungs infected by the virus. respiratory infection caused by a virus .

medical human illness medicine vector flu antibiotic infected lung biology concept contagious virus diagnosis breath breathe bronchitis pneumonia fever health disease immunity infect lethal medicals microbiology pandemic pathology science symptom treatment vaccine virology radiography medic x-ray asthma cancer person chest exam pulmonary stethoscope infection nurse hospital care nodule transplant lungs logo design respiratory caused design virus illustra