Researchers find clues to 'Long COVID'

A research team led by doctors from three top Chinese hospitals has made a significant breakthrough in understanding so-called Long COVID, which will aid in the early identification of high-risk individuals and provide molecular-level clues for studying the mechanisms of the disease, Beijing Daily reported on Wednesday.

Team members from the China-Japan Friendship Hospital, Peking Union Medical College Hospital and Wuhan Jinyintan Hospital published their findings recently in a subsidiary of The Lancet, the prestigious international medical journal.

They said that about 10 percent of the global population infected with the novel coronavirus develops Long COVID, which affects multiple organ systems.

They noted the presence of residual virus in tissues after infection, cross-reactivity between specific antibodies against the coronavirus and host proteins, leading to autoimmune reactions and other possibilities. However, these hypotheses still need further verification.

At present, the diagnosis and treatment of Long COVID remain challenging, primarily due to the lack of biomarkers for early identification and intervention. Therefore, it is crucial to find the biological recovery patterns of COVID-19 patients over a longer time span and explore important proteins that may influence long-term outcomes in order to study the mechanisms of Long COVID.

The study has enrolled 181 COVID-19 patients who were discharged from Wuhan Jinyintan Hospital from January to May 2020 and compared them with a control group consisting of 181 individuals who were matched in terms of age and gender but had not been infected with COVID-19.

The teams collected blood plasma samples from both the COVID-19 patients and the control group at three time points — six months, one year and three years after infection, and conducted a specialized analysis.