Six years after COVID-19 first appeared, the world has become markedly different than it was in 2020. The initial shock of a novel, unpredictable, and deadly virus has given way to a long-term reality in which COVID-19 continues to shape public health, medical practice, and the lives of millions. Although the acute global emergency has passed, the pandemic’s legacy remains deeply embedded in society, medicine, and the bodies of those who were infected.
Today, COVID-19 behaves like an endemic respiratory virus in many regions. Widespread immunity—achieved through vaccines, prior infections, or both—has significantly reduced the severity of disease for much of the population. Hospitalizations and deaths occur at far lower rates than during the initial pandemic years. Yet the virus still circulates broadly, producing periodic surges and continuing to cause significant illness, particularly among high-risk groups such as older adults, the immunocompromised, and those who are unvaccinated or under-vaccinated. Despite a common public perception that “COVID is over,” the virus persists as a substantial, if less dramatic, public health concern, much in the same way that the flu does.
Perhaps the most consequential long-term impact of the pandemic is the lingering constellation of symptoms known as long COVID or post-COVID-19 condition. Six years after the virus first emerged, research continues to affirm that long COVID is both real and widespread. Longitudinal studies show that a sizable proportion of individuals—many of whom had mild initial infections—still report symptoms such as fatigue, shortness of breath, and sleep disturbances years after recovery. Some experience measurable physiological changes, including impaired lung diffusion capacity. Others face cognitive, cardiovascular, or endocrine complications. These long-term effects impose a persistent burden on individuals, families, and healthcare systems and have become one of the defining challenges of the post-pandemic era.
Parallel to clinical observations, scientific research has made significant progress in understanding why some people develop extended symptoms. Recent studies suggest that pre-existing medical conditions, patterns of health in the years before infection, and genetic susceptibility all play roles in determining who is most vulnerable to prolonged illness. Researchers have yet to identify a single mechanism that explains all cases; instead, long COVID appears to be a heterogeneous syndrome affecting multiple organ systems in different ways. This complexity underscores the need for personalized approaches to diagnosis and treatment. Meanwhile, new evidence also hints at increased risks following COVID-19 infection for certain autoimmune or autoinflammatory disorders—an emerging concern that warrants deeper investigation.
These scientific and clinical developments carry significant implications for public health and healthcare system planning. Even though the threat of overwhelming hospital surges has diminished, the long-term burden of COVID-19 continues to strain medical resources. Many healthcare settings still lack standardized guidelines for evaluating or treating long COVID, leaving patients to navigate inconsistent care. Improved training, clearer diagnostic protocols, and expanded rehabilitation services are essential to meet the ongoing demand. At the same time, the experience of COVID-19 has reshaped how public health agencies and societies think about preparedness, crisis communication, infection control, and the intersection of social inequality with health outcomes.
Six years after the first cases of COVID-19 emerged, the virus no longer presents the acute global emergency it once did, but it is far from gone. The virus has shifted from crisis to chronic challenge, leaving a complex medical and social legacy. Understanding and addressing its long-term consequences, strengthening healthcare systems, and improving resilience for future public health threats remain essential steps as the world learns to live with the continued presence of COVID-19.
References
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4. Long COVID Clinical Evaluation, Research and Impact on Society: A Global Expert Consensus. Ann Clin Microbiol Antimicrob. 2025;24:27. DOI: 10.1186/s12941-025-00793-9
5. Long-Term Risk of Autoimmune and Autoinflammatory Connective Tissue Disorders Following COVID-19. JAMA Dermatol. 2025. 10.1001/jamadermatol.2024.4233