Understanding Long COVID: Causes, Prevention, and What Travelers Should Know
Long COVID remains a significant concern for many individuals recovering from SARS-CoV-2 infection. Although most people recover fully within a few weeks, some experience persistent symptoms that can last for months or even longer. Understanding what drives this condition and how to reduce the risk is essential, especially for those planning international travel.
What Is Long COVID?
Long COVID, also referred to as post-acute sequelae of SARS-CoV-2 infection (PASC), encompasses a wide range of new, returning, or ongoing health problems that people experience after initially being infected with the virus that causes COVID-19. Symptoms can affect multiple organ systems and vary widely from person to person.
According to the CDC, common symptoms include fatigue, shortness of breath, cough, joint pain, chest pain, difficulty concentrating (“brain fog”), depression, muscle pain, headache, intermittent fever, and heart palpitations. These symptoms may persist for weeks or months after the acute phase of illness and can significantly impact daily functioning.
What Causes Long COVID?
The exact mechanisms behind Long COVID are still under investigation, but current evidence indicates that the SARS-CoV-2 virus itself plays a central role. Research suggests that viral persistence, immune system dysregulation, inflammation, and potential autoimmune responses triggered by the infection may contribute to prolonged symptoms.
The CDC notes that while vaccination can reduce the risk of developing Long COVID, data on whether antiviral treatments during acute infection lower this risk remain mixed. This underscores the importance of preventive measures, particularly for individuals at higher risk due to age, underlying health conditions, or exposure levels.
Related Conditions: Multisystem Inflammatory Syndrome (MIS)
In some cases, particularly among children and adolescents, SARS-CoV-2 infection can lead to multisystem inflammatory syndrome (MIS), a rare but serious condition where different body parts develop into inflamed — including the heart, lungs, kidneys, brain, skin, eyes, or gastrointestinal organs. MIS typically occurs 2 to 6 weeks after the initial infection and requires prompt medical attention.
Although MIS is more commonly reported in younger populations, adults can also develop a similar condition known as MIS-A. Both conditions highlight the systemic impact that SARS-CoV-2 can have beyond the respiratory system.
Prevention Strategies for Travelers
For individuals planning international travel, taking proactive steps to prevent COVID-19 infection is the most effective way to reduce the risk of Long COVID. The CDC recommends staying up to date with COVID-19 vaccinations, which remain a key tool in preventing severe illness, hospitalization, and death.
Additional preventive measures include wearing well-fitting masks or respirators in crowded or poorly ventilated indoor settings, practicing good hand hygiene, improving indoor ventilation when possible, and avoiding close contact with individuals who are sick.
Before traveling, consulting with a healthcare provider is advised — ideally four to six weeks prior to departure — to review vaccination status, discuss destination-specific risks, and develop a personalized prevention plan. This is especially essential for travelers with immunocompromising conditions or chronic medical illnesses.
Testing and Preparedness While Abroad
Even with precautions, travelers may still be exposed to SARS-CoV-2 while abroad. Having access to reliable testing options — such as point-of-care rapid tests or laboratory-based diagnostics — can facilitate identify infection early, allowing for timely isolation and care.
Travelers should also consider what steps they would take if they test positive while overseas, including knowing how to access medical care, understanding local public health guidelines, and having a plan for extended stay if needed due to illness.
The Bottom Line
Long COVID is a real and potentially debilitating consequence of SARS-CoV-2 infection, driven by the virus’s impact on the body rather than external factors. While research continues to uncover the biological mechanisms behind prolonged symptoms, current evidence supports vaccination and infection prevention as the most effective strategies to reduce risk.
For travelers, integrating COVID-19 precautions into pre-trip planning — including vaccination, testing readiness, and consultation with a healthcare provider — remains a critical component of safe and healthy international travel in 2026.
References:
- CDC. COVID-19. Yellow Book: Health Information for International Travel. 2026. Available at: https://www.cdc.gov/yellow-book/hcp/travel-associated-infections-diseases/covid-19.html
- Mayo Clinic. Coronavirus disease 2019 (COVID-19). Travel advice. Available at: https://www.mayoclinic.org/diseases-conditions/coronavirus/in-depth/coronavirus-safe-travel-advice/art-20486965
- CVS Health. MinuteClinic® Pre-travel Health Consultation. Available at: https://www.cvs.com/minuteclinic/services/pre-travel-consultation