What Is Long COVID?

Key characteristics of long COVID

• Persistent symptoms: Long COVID involves a wide range of symptoms that continue beyond the acute infection phase, lasting from weeks to years, characterizing the post-COVID syndrome

• Multi-system impact: It affects multiple body systems, leading to a variety of long COVID symptoms including:

  • Cardiovascular: Palpitations, chest pain
  • Respiratory: Dyspnea (shortness of breath), cough
  • Neurological: Brain fog, cognitive impairment
  • Musculoskeletal: Joint pain, muscle weakness
  • General: Fatigue, hair loss

• Varying severity: Experiences of post-COVID syndrome range from mild persistent symptoms to severe symptoms of varying durations

• No clear definition: Long COVID remains a fluid situation with no universally established definition of what is long COVID

Comparison to other viral respiratory infections

• Unique sequelae: SARS-CoV-2 infection is associated with higher rates of certain conditions compared to common viral respiratory infections (VRIs), contributing to the understanding of what is long COVID:

  • Palpitations
  • Hair loss
  • Fatigue
  • Chest pain
  • Dyspnea
  • Joint pain
  • Obesity

• Similar symptoms: Some long COVID symptoms commonly described are not significantly more frequent than those seen in other VRIs

• Increased risks: Post-COVID syndrome is associated with higher risks of developing:

  • Type 1 diabetes
  • Acute respiratory distress syndrome (ARDS)
  • Pulmonary embolism
  • Hypoxemia
  • Tachycardia

Diagnostic challenges

• Diverse symptom profile: With 200+ long COVID symptoms associated with the condition, diagnosis can be challenging

• Lack of specific biomarkers: While research is ongoing, there are currently no definitive biomarkers for long COVID diagnosis

• Persistent inflammation: Complement fragments, part of the immune system, can remain elevated in the blood of post-COVID syndrome patients for years after infection, indicating ongoing inflammation

Risk factors and protective elements

• Risk factors: Obesity and hypertension are associated with increased risk of developing long COVID

• Protective factor: Interestingly, nicotine dependence/tobacco use appears to be a protective factor against post-COVID syndrome

Ongoing research and treatment

• Multidisciplinary approach: Understanding what is long COVID requires research in epidemiology, burden of disease, and behavioral aspects to comprehend its pathophysiology and risk factors

• Potential new chronic disease: The persistent morbidity outcomes of long COVID symptoms are being considered as a potential new chronic disease

FAQ

What is long COVID?

Long COVID, also known as post-COVID syndrome, is a complex condition where COVID-19 survivors experience persistent symptoms for weeks, months, or even years after the initial infection. It affects multiple body systems and can involve over 200 different symptoms.

What are the most common long COVID symptoms?

The most common long COVID symptoms include fatigue, brain fog, shortness of breath, palpitations, chest pain, joint pain, muscle weakness, and hair loss. These symptoms can vary in severity and duration among individuals.

How long can post-COVID syndrome last?

Post-COVID syndrome can last for weeks, months, or even years after the initial COVID-19 infection. The duration varies greatly among individuals, with some experiencing mild persistent symptoms and others facing severe, long-lasting effects.

How is long COVID different from other viral respiratory infections?

Long COVID is associated with higher rates of certain conditions compared to common viral respiratory infections, including palpitations, hair loss, fatigue, chest pain, dyspnea, and joint pain. It also carries increased risks for developing type 1 diabetes, acute respiratory distress syndrome, and pulmonary embolism.

What are the risk factors for developing post-COVID syndrome?

Obesity and hypertension are associated with an increased risk of developing long COVID. Interestingly, nicotine dependence or tobacco use appears to be a protective factor against post-COVID syndrome. However, more research is needed to fully understand the risk factors and protective elements.