Table 1.

Summary of symptoms, mechanisms and treatment targets of acute and chronic phases of COVID-19

	Acute phase (first 4 weeks from infection)	Chronic phase (after 4 weeks)
Symptoms	• Nasopharyngeal (sore throat, runny nose) • Respiratory (cough, dyspnea) • Systemic (fever, headache, fatigue)	• Respiratory (persistent cough, dyspnea, hypoxia) • Cardiovascular (palpitation, chest pain) • Neurological (headache, dizziness, numbness) • Neuropsychiatric (short-term memory loss, inability to concentrate, depression, anxiety) • Systemic (fatigue, muscular weakness, insomnia)
Known mechanisms	• Viral attack • Inflammatory response • Cytokine storm	• Immune response • Chronic inflammation • Pulmonary fibrosis • Coagulopathy
Treatment targets	• Anti-viral medications • Immunomodulatory agents (cytokine inhibitors, immune globulin)	• Supportive management • Rehabilitation • Vaccination • Anti-coagulation