COVID-19: Symptoms, Testing & Treatment

COVID-19 is an infectious disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The disease primarily affects the respiratory system but can impact multiple organs. Most infected persons develop mild to moderate disease, while some (particularly elderly and immunocompromised individuals) develop severe illness requiring hospitalization and mechanical ventilation.

The virus emerged in late 2019 in Wuhan, China, and spread globally, becoming a pandemic.

Transmission occurs through:

• Respiratory droplets from infected persons
• Aerosol transmission in poorly ventilated spaces
• Close contact with infected individuals
• Contaminated surfaces (less common)

Risk factors for severe illness:

• Age over 65 years
• Chronic medical conditions
• Immunosuppression
• Obesity
• Pregnancy
• Unvaccinated status

Symptoms appear 2-14 days after exposure:

• Fever or chills
• Cough (usually dry)
• Fatigue
• Loss of taste or smell
• Difficulty breathing (severe cases)
• Headache
• Sore throat
• Congestion or runny nose

Many infected persons are asymptomatic.

Diagnosis involves:

• RT-PCR testing (gold standard)
• Rapid antigen tests
• Antibody/serology testing
• CT chest imaging (for severe cases)

Mild disease:

• Supportive care
• Acetaminophen or ibuprofen
• Rest and hydration
• Isolation to prevent spread

Moderate to severe disease:

• Hospitalization
• Supplemental oxygen
• Antiviral therapy (remdesivir)
• Immunomodulatory agents (dexamethasone)
• Monoclonal antibodies (early infection)

Primary prevention:

• COVID-19 vaccination (all available vaccines safe and effective)
• Boosters as recommended
• Masking in high-transmission settings
• Improving ventilation
• Isolation when sick
• Testing and quarantine guidance

See a doctor if symptoms worsen or persist beyond 2 weeks. Those in high-risk groups should seek early treatment. Long-term symptoms (long COVID) warrant medical evaluation.