Overview
COVID-19 is a contagious respiratory illness caused by the SARS-CoV-2 virus that emerged in late 2019. It can range from mild cold-like symptoms to severe pneumonia, multi-organ failure, and death.
Vaccines have greatly reduced severe and fatal forms of the disease. During the pandemic, millions of people were affected.
Symptoms
Symptoms appear 2-14 days (average 5 days) after exposure to the virus:
Common symptoms:
- Fever, chills
- Cough (dry or productive)
- Fatigue, weakness
- Sore throat
- Headache
- Muscle and joint aches
- Runny or stuffy nose
- Loss of smell and taste (especially with early variants)
Less common symptoms:
- Diarrhea, nausea, vomiting
- Abdominal pain
- Conjunctivitis (eye redness)
- Skin rashes
Severe symptoms (require emergency care):
- Shortness of breath, difficulty breathing
- Persistent chest pain or pressure
- Bluish lips or face
- Confusion, loss of consciousness
- Inability to speak or move
Causes
The SARS-CoV-2 virus spreads through droplets and aerosols released by coughing, sneezing, talking, or breathing. Close contact and poorly ventilated indoor settings increase the risk of transmission.
Risk Factors (For Severe Disease)
- Age 65 and older
- Chronic diseases (diabetes, heart, lung, kidney)
- Obesity
- Cancer
- Use of immunosuppressive drugs
- Pregnancy
- Smoking
- Being unvaccinated
Complications
- Acute respiratory distress syndrome (ARDS)
- Pneumonia
- Thromboembolic events (blood clots)
- Heart involvement (myocarditis)
- Kidney failure
- Multi-organ failure
- Secondary bacterial infections
- Long COVID: Fatigue, shortness of breath, brain fog, palpitations lasting for months
- MIS-C in children: Multisystem inflammatory syndrome
When to See a Doctor
Emergency situations:
- Shortness of breath
- Persistent chest pain
- Confusion
- Bluish lips/face
- High fever lasting more than 3 days
Mild cases can be managed with home isolation and monitoring. High-risk patients should see a doctor early for antiviral treatment.
Diagnosis and Treatment
Diagnosis:
- PCR test (gold standard)
- Rapid antigen test
- Antibody test (for past infection)
- Lung CT (in case of complications)
Treatment:
- Mild cases: rest at home, plenty of fluids, paracetamol
- Early antiviral treatment in risk groups (paxlovid, molnupiravir)
- Hospital treatment: oxygen, corticosteroids (dexamethasone), anticoagulants
- Severe cases: intensive care, mechanical ventilation
- Antibiotics only if bacterial complications develop
Prevention
- Vaccination: The most effective protective method; do not skip booster doses
- Wear masks (in crowded indoor places)
- Wash hands frequently or use hand sanitizer
- Ventilate indoor spaces
- Avoid sick people
- Stay home and get tested if you have symptoms
- Maintain a strong immune system
- Protect risk groups