"We've uncovered 99 cases of persistent COVID in people who hadn't seen a doctor."

BarcelonaAmong the many consequences of the COVID-19 pandemic, there is one that still complicates the lives of hundreds of Catalans: persistent COVID-19, a condition that prolongs the symptoms caused by the virus for at least three months after infection. However, some affected individuals have been battling daily after-effects such as brain fog, memory loss, joint pain, and physical exhaustion for five years; the same number of years since the pathogen first made its rounds around the world. Others don't know it, but the headaches and muscle pain that occasionally incapacitate them from day to day can also be caused by persistent COVID-19. This is indicated by a pioneering investigation by the Terrassa Health Consortium (CST), which has uncovered 99 new cases in the Barcelona metropolitan area involving people who had not sought help despite having suffered compatible symptoms, especially women who had been infected more than once.

Toni Arévalo, director of the Castellbisbal Primary Care Centre (CST), leads the research project for the care of people with persistent COVID-19 at the CST, funded by the Department of Health. The true prevalence of persistent COVID-19 in Catalonia, that is, how many people who have had the infection suffer the after-effects, is still unknown. "At the beginning of the pandemic, it was estimated that it could affect 20% of those infected, but there is no conclusive data," the doctor explains to ARA. Therefore, the study has two main objectives: to determine how many people are affected by this condition—recently recognized by the Ministry of Health as a chronic disease—and to design non-pharmacological treatments to improve the quality of life of patients.

Regarding the first objective, the professionals explain that the CST initially had around 350 documented cases of persistent COVID. Starting in 2023, the number of diagnoses decreased because diagnostic testing was reserved for high-risk individuals. However, with the retrospective study, they were able to identify 26% more, or 99 additional affected individuals. Most began experiencing symptoms in 2020, although they had not seen a doctor. "Although they suffer from joint pain, chronic fatigue, unexplained headaches, or olfactory disturbances, they have not consulted a doctor because they do not consider their daily lives to have been so altered," adds Arévalo, who says that they have been tested to rule out other pathologies.

The risk increases with reinfections

Analyzing data collected between March 2020 and March 2025, the results indicate that at least 2.4% of every thousand inhabitants of the Consortium's reference population (192,650 people) have suffered from persistent COVID. The condition affects young women (3.3 per 1,000) more than men (1.6 per 1,000), especially those between 30 and 59 years old and those who were infected before receiving their first vaccine.

The risk increases even further with reinfections: it is between 3 and 10 times higher in those who have had the virus three or more times. Arévalo also points to the unvaccinated or those who were vaccinated after becoming infected. "It is recommended to always remain vaccinated, especially 3 to 6 months after infection," insists the expert, who also recommends the use of masks for healthcare professionals during the respiratory virus season.

The study also includes a questionnaire for those affected to measure how they rated their quality of life. Before the pandemic, they rated their health status with an average of 8.2 points. The result has decreased by more than 2.5 points now, indicating a clear deterioration in their perception of health and daily performance.