From the Guidelines
Yes, individuals can experience relapses of Post-Acute COVID-19 symptoms long after initial infection, with symptoms persisting for weeks, months, or even years. Long COVID is characterized by persistent or recurring symptoms that continue after the acute phase of COVID-19 infection has resolved. These relapses, sometimes called "flares," can occur unpredictably and may be triggered by physical exertion, stress, inadequate rest, or other infections 1. Common relapsing symptoms include:
- Fatigue
- Brain fog
- Shortness of breath
- Chest pain
- Neurological issues
There is no standardized medication regimen for long COVID relapses, but treatment typically focuses on symptom management. Some patients benefit from a pacing approach to conserve energy, gradually increasing activity levels while avoiding post-exertional malaise. The biological mechanisms behind these relapses are still being studied but may involve persistent viral reservoirs, autoimmune reactions, microclots, or mitochondrial dysfunction 1. Recovery patterns vary significantly between individuals, with some experiencing improvement over time while others continue to have cyclical symptoms for extended periods. According to a recent study, few people with long COVID demonstrate full recovery, with one study finding that 85% of patients who had symptoms 2 months after the initial infection reported symptoms 1 year after symptom onset 1.
The onset and time course of symptoms differ across individuals and by symptom type, with neurological symptoms often having a delayed onset of weeks to months 1. Some symptoms, such as gastrointestinal and respiratory symptoms, are more likely to resolve, whereas neurocognitive symptoms worsen over time and tend to persist longer. Diagnoses of ME/CFS and dysautonomia are generally lifelong, and future prognosis is uncertain 1. The current understanding of long COVID is based on limited evidence, and further research is needed to fully understand its mechanisms and develop effective treatments.
From the Research
Post-Acute COVID-19 Symptoms
- Individuals can experience relapses of Post-Acute COVID-19 symptoms long after initial infection, with studies indicating that 85.9% of participants experienced relapses, primarily triggered by exercise, physical or mental activity, and stress 2.
- The time to recovery exceeded 35 weeks for the majority of respondents, with symptoms varying in their prevalence over time 2.
- Long COVID-19 Syndrome refers to survivors 4 months after initial symptoms onset, with various unresolved symptoms reported in COVID-19 survivors months after hospital discharge 3.
Frequency and Nature of Persistent Symptoms
- The frequency of persistent symptoms in patients after mild COVID-19 infection ranged between 10% and 35%, with fatigue being the most frequently described persistent symptom 4.
- Symptoms persisting after a mild COVID-19 infection can be distinguished into physical, mental, and social symptoms, including dyspnoea, cough, chest pain, headache, decreased mental and cognitive status, and olfactory dysfunction 4.
- Long COVID can be debilitating, with 45.2% of patients requiring a reduced work schedule, and an additional 22.3% not working at the time of survey due to illness 2.
Pathophysiology and Mechanism of Long COVID
- The underlying pathophysiology of long COVID is still enigmatic, but studies suggest that it likely results from long-term organ damage due to acute-phase infection, as well as specific mechanisms following the initial illness, such as autonomic nervous system damage, immune dysregulation, auto-immunity, endothelial dysfunction, occult viral persistence, and coagulation activation 5.
- Long COVID is a multisystem disease that develops regardless of the initial disease severity, with its clinical spectrum comprising a wide range of symptoms 5.
- Existing studies involving Long-COVID patients are highly heterogeneous, including patients with various COVID-19 severity levels and different time frame analysis 5.