Long COVID continues to cast a long shadow, affecting not only adults but also the youngest members of society, with symptoms persisting for years after initial infection. Recent comprehensive studies have shed light on the enduring impact of COVID-19, revealing that millions worldwide, including infants, toddlers, and preschool-aged children, face prolonged health challenges that complicate recovery and daily life.
A meta-analysis published in the Journal of Medical Virology has brought into focus the long-term burden experienced by adults who contracted COVID-19, particularly those hospitalized during the early waves of the pandemic. This analysis combined data from 11 observational studies conducted across six countries—Bulgaria, China, Japan, Italy, Romania, and the United States—encompassing 142,171 patients aged 36 to 86 years, 87% of whom were men. The findings are sobering: approximately 20% of these patients reported at least one persistent symptom three years after their initial infection.
The most common lingering symptoms among these adults include fatigue, sleep disturbances such as insomnia, and shortness of breath, affecting roughly 11-12% of patients each. Other notable complaints are loss of smell or taste, each reported by 7%, and anxiety, experienced by 6%. Beyond these symptoms, physiological impairments remain prevalent, with 42% showing poor lung diffusion capacity and 10% exhibiting reduced forced expiratory volume in one second, indicating lasting respiratory challenges.
Alarmingly, the risk of death remains elevated three years post-infection for those hospitalized with COVID-19, with an incidence rate ratio of 1.29 and an excess burden of 8.16 deaths per 1,000 persons. Mortality rates were notably higher among patients exhibiting neurological symptoms—14% compared to 7.8% in those without such signs. The study also quantified the disability burden, attributing 90 disability-adjusted life years (DALYs) per 1,000 hospitalized patients and 9.6 DALYs per 1,000 nonhospitalized patients three years after infection.
Neurological, pulmonary, and cardiovascular symptoms dominate the spectrum of long COVID manifestations. Patients frequently report impaired memory, dizziness, peripheral neuropathy, and mental health conditions such as anxiety and depression. Cardiovascular complications include heart failure and abnormal heart rhythms, underscoring the multifaceted nature of the disease's aftermath.
Risk factors for prolonged symptoms are diverse, encompassing older age, greater initial disease severity, hospitalization, female sex, smoking, substance use, allergies, and preexisting conditions like congestive heart failure, chronic kidney disease, hypertension, and diabetes. The researchers emphasize the urgent need for multidisciplinary care teams and integration of long COVID management into standard healthcare protocols. They also call for public health campaigns to raise awareness and reduce stigma surrounding the condition.
Drawing parallels with the 2003 SARS epidemic, the authors note that 38% of SARS survivors still exhibited reduced lung diffusion capacity 15 years later, highlighting the potential for long-lasting respiratory damage following coronavirus infections. They stress the importance of ongoing monitoring and targeted interventions to mitigate the enduring impact of COVID-19.
While much attention has been paid to adults, a groundbreaking study published in JAMA Pediatrics reveals that long COVID is also a significant concern for young children. The National Institutes of Health (NIH)–funded RECOVER–Pediatrics cohort study, part of the $1.15 billion Researching COVID to Enhance Recovery (RECOVER) initiative launched in August 2022, examined 472 infants and toddlers alongside 539 preschool-aged children across multiple U.S. sites. Of these, 278 infants/toddlers and 399 preschoolers had evidence of prior SARS-CoV-2 infection.
The study found that 14% of infants and toddlers and 15% of preschool-aged children could be classified as suffering from long COVID, with even higher percentages—41% and 45%, respectively—experiencing at least one prolonged symptom. These rates starkly contrast with uninfected children, among whom only 3% of infants/toddlers and 6% of preschoolers reported prolonged symptoms. Notably, the study excluded children with multisystem inflammatory syndrome in children (MIS-C), suggesting that the actual burden of COVID-19-related morbidity in children could be even greater.
Distinct symptom patterns emerged between the two age groups. Infants and toddlers exhibited five symptoms highly indicative of prior infection: poor appetite (the strongest indicator), trouble sleeping, wet cough, dry cough, and stuffy nose. Preschool-aged children showed two key symptoms: daytime tiredness (the strongest indicator) and dry cough. The study also revealed that the rate of long COVID in infants and toddlers declined from 20% pre-Omicron to 13% post-Omicron, while preschool-aged children maintained a consistent 15% rate across both periods.
To better identify probable long COVID cases, researchers developed and validated a symptom index assigning weighted scores to symptoms based on their correlation with prior infection. Higher index scores correlated strongly with poorer overall health, reduced quality of life, and delayed developmental milestones, underscoring the profound impact of long COVID on young children's wellbeing and growth.
The RECOVER–Pediatrics study is the first large-scale, multi-site investigation into long COVID in early childhood, marking a critical step forward in understanding how the disease affects the youngest populations. Importantly, the study found that prolonged symptoms in these children were linked to SARS-CoV-2 infection but not to other common childhood viruses like influenza or respiratory syncytial virus (RSV).
Despite its strengths, the study acknowledges limitations, including reliance on caregiver-reported symptoms and the inability to test all children for prior infection due to parental reluctance for blood draws. These factors might have led to underestimating the differences between infected and uninfected children. The symptom indexes are intended for research purposes and not clinical diagnosis, but they provide a valuable tool for tracking symptom progression over time. Researchers plan to follow these children longitudinally to better understand the trajectory of long COVID in early childhood.
The emergence of these findings comes amid ongoing challenges in public health policy and scientific funding. Earlier in 2025, NIH canceled numerous grants related to the RECOVER initiative, including those focused on long COVID, only to restore some funding following significant public and scientific outcry. Concurrently, political debates have intensified, with recent moves to remove COVID-19 vaccination recommendations for children and pregnant women from the Centers for Disease Control and Prevention’s schedule, despite evidence supporting vaccination's protective effect against long COVID.
David Goff, M.D., Ph.D., division director for the Division of Cardiovascular Sciences at NIH’s National Heart, Lung, and Blood Institute, emphasized the importance of recognizing the unique manifestations of long COVID in children: "Most research characterizing long COVID symptoms is focused on adults, which can lead to the misperception that long COVID in children is rare or that their symptoms are like those of adults. Because the symptoms can vary from child to child or present in different patterns, without a proper characterization of symptoms across the life span, it’s difficult to know how to optimize care for affected children and adolescents."
These studies collectively highlight a pressing reality: long COVID is a complex, multifaceted condition that demands sustained attention, comprehensive care strategies, and robust research efforts across all age groups. From adults grappling with lingering neurological and respiratory symptoms years after hospitalization to young children facing developmental delays and persistent health challenges, the pandemic's shadow remains long and pervasive.
As the world navigates the post-acute phase of the COVID-19 pandemic, integrating multidisciplinary care, expanding long-term monitoring, and prioritizing public health initiatives are essential steps. The lessons learned from SARS and now COVID-19 underline the critical need to prepare healthcare systems for the enduring aftermath of viral pandemics, ensuring that survivors receive the support and resources necessary to reclaim their health and quality of life.