Research Sheds Light on Potential Contributors to Prolonged Symptoms

A British historian, an Italian archaeologist, and an American preschool teacher share a unique connection through their contributions to the understanding of long COVID, which they helped to bring to public awareness in early 2020. Despite never meeting, these three women experienced similar debilitating symptoms following a coronavirus infection.

Rachel Pope from Liverpool detailed her struggles on Twitter in March 2020, describing her ongoing, unnamed symptoms. Shortly after, Elisa Perego in Italy coined the term “long COVID” in a tweet. Meanwhile, Amy Watson in Portland, Oregon, named her Facebook support group “long haulers,” a term that quickly entered the pandemic vocabulary.

Almost three years into the pandemic, scientists are still exploring why some individuals develop long COVID, with millions reporting symptoms like fatigue, lung issues, and cognitive difficulties. While many recover within a year, recent data indicate that long COVID has been linked to over 3,500 deaths in the U.S.

Are Women More Vulnerable?
Numerous studies suggest that women may be at greater risk of developing long COVID. Biological factors could play a role; women generally exhibit stronger immune responses to infections, according to Sabra Klein, a professor at Johns Hopkins who studies immunity.

Additionally, women are more prone to autoimmune diseases, which could lead to long COVID symptoms triggered by the virus. Emerging research also indicates that the coronavirus may reside in fat cells post-infection, and it’s noted that women typically have a higher proportion of fat tissue. Furthermore, fluctuations in hormone levels might contribute to increased risks.

Klein points out that women are often more proactive in seeking healthcare and may be more attuned to changes in their health, suggesting that both biological and behavioural factors are significant.

The Role of the Epstein-Barr Virus
Several studies indicate that the Epstein-Barr virus, known for causing mononucleosis, could be implicated in some long COVID cases. Dr. Timothy Henrich from UCSF explains that inflammation from a coronavirus infection can reactivate dormant herpes viruses. He has identified immune markers associated with Epstein-Barr reactivation in some long COVID patients, particularly those experiencing fatigue.

While not all long COVID patients exhibit these markers, the possibility remains that Epstein-Barr could be responsible for symptoms in those who do. Some researchers are also investigating links between Epstein-Barr and chronic fatigue syndrome, which shares similarities with long COVID.

Obesity as a Contributing Factor
Obesity has been identified as a risk factor for severe COVID-19 infections, leading scientists to investigate its role in long COVID. Recent research from Stanford University indicates that the coronavirus may infect fat cells, with evidence of the virus and inflammation found in fat tissue from deceased COVID patients. This raises the possibility that fat cells could act as reservoirs for the virus, potentially exacerbating long COVID symptoms.

Researchers are exploring whether reducing fat tissue might help treat or prevent long COVID. Concurrently, studies at the University of Texas Southwestern Medical Center are examining leptin, a hormone produced by fat cells that influences immune responses and inflammation.

Duration of Symptoms
Estimates suggest that around 30% of individuals infected with the coronavirus may develop long COVID. Most who experience lingering symptoms after infection tend to recover within three months. However, about 15% of those still symptomatic at three months may continue to experience symptoms for nine months or longer, according to a recent Journal of the American Medical Association study.

Identifying individuals at risk for prolonged symptoms remains complex. While those with severe infections are generally more susceptible, milder cases can also lead to long COVID. Patients with significant lung damage may suffer from breathlessness, coughing, or fatigue for over a year, while some with mild initial infections might experience neurological issues like chronic fatigue and brain fog.

Dr. Lawrence Purpura, an infectious disease expert, reassures that most patients eventually recover but acknowledges the ongoing struggles of those affected.

Perego, now 44, continues to face serious health challenges, including heart and lung issues. She recognizes the progress made in research but highlights the gap between scientific understanding and effective medical care.

Watson, nearing 50, reports no recovery, grappling with severe migraines and other health problems. She expresses frustration with the lack of a structured approach to treating long COVID, wishing for a clearer path to regaining her former quality of life. “I just want my life back,” she laments.