Unraveling the Causes and Treatments of Long Covid: The Ongoing Quest for Answers
Heather Marti, a university program administrator from West Virginia, contracted Covid-19 in August 2021. Two months later, she began experiencing a terrifying array of symptoms that have completely changed her life. Marti describes agonizing muscle pain, gastrointestinal problems, weeks-long migraine-like headaches, brain fog, and extreme mental fatigue. She compares the feeling to having all the wires in her body crossed, causing dysfunction in every system. Marti’s search for answers is not unique. Four years after the emergence of the Covid-19 pandemic, the quest to uncover the causes of long Covid and develop treatments for the condition continues.
According to the World Health Organization (WHO), approximately 6% of those who contract Covid-19 end up with long Covid. This condition is defined as the continuation or development of symptoms three months after initial infection with Sars-Cov-2, with these symptoms lasting for at least two months. In Europe alone, at least 17 million people have joined the ranks of “long-haulers” in the first two years of the pandemic. Melissa Heightman, who opened one of the first specialist long Covid clinics at University College London Hospitals in the UK, acknowledges that finding a simple cure or silver bullet is unlikely due to the complex nature of the condition.
One of the biggest shocks for experts studying long Covid is that many sufferers were never severely ill with the virus in the first place. Walter Koroshetz, co-chair of a nationwide research program at the US National Institutes of Health (NIH), designed to uncover the biologic mechanisms behind long Covid, explains that hospitals initially set up clinics to support those who had been in intensive care. However, they soon realized that even mild or moderate cases could lead to prolonged after-effects. The NIH’s Recover Initiative aims to provide answers not only for long Covid but also for myalgic encephalomyelitis, another post-viral condition commonly known as chronic fatigue syndrome.
Researchers believe that long Covid sufferers, especially those who experienced severe infections, may never have fully rid their bodies of the virus. This allows the virus to continue replicating or leaves behind remnants even after testing negative. This persistent activation of the immune system can cause chronic symptoms. Autopsy-based studies conducted by the NIH found evidence of active traces of the Covid virus in some individuals who died up to 280 days after becoming infected with severe disease. A longer course of antiviral drugs could potentially eliminate any remaining pockets of the virus.
Another theory suggests that long Covid is primarily an autoimmune disorder. This means that the immune systems of sufferers become overactive, attacking healthy cells. The NIH’s Recover investigators are testing an autoimmune treatment called intravenous gamma globulin (IVIG), which resets the immune system and acts as an immune suppressant. In addition to these approaches, metabolic drugs like Metformin and dietary supplements are being tested to alleviate symptoms.
The extreme tiredness associated with long Covid is a crucial indicator of how quickly a patient will recover. Severe fatigue often leads to slow recovery. While classic long Covid is characterized by a specific set of symptoms that scientists are still trying to understand, some researchers are focused on the link between infection and an increased risk of heart disease, stroke, and diabetes. Patients who have recovered from Covid are more likely to suffer from these conditions compared to those who have not contracted the disease.
Ziyad al-Aly, R&D chief at Veterans Affairs St Louis Health Care System and clinical epidemiologist at Washington University in St Louis, discovered this link in data from the VA’s extensive database. Similar findings were evident in data from countries like Germany and the UK. However, Aly and his colleagues are examining whether people infected with the Omicron variant are less likely to face a heightened health risk compared to those who contracted earlier versions of the virus. They plan to publish their conclusions later this year.
Heightman emphasizes that the original “wild type” of the virus seems to be the most severe, while vaccination not only reduces the chances of developing long Covid in breakthrough infections but also appears to reduce the severity of the condition. However, Aly warns that Covid’s enduring impact on health is such that the incidence of diseases like strokes has permanently risen. He believes that governments have not fully grasped the costly implications for healthcare systems and that there is a lack of concern regarding the level of spending required on healthcare resources.
The ongoing quest for answers to long Covid continues, with researchers exploring various causes and potential treatments. While there may not be a simple cure, advancements in understanding the condition and its mechanisms offer hope for improved management and support for long-haulers like Heather Marti.