Manali Mukherjee
For connecting COVID to autoimmune diseases
Medical researchers have long identified a connection between viral infections and increased risk of autoimmune problems. Measles and mumps, for example, have been linked to the onset of type 1 diabetes, while a bout of mononucleosis (caused by the Epstein-Barr Virus) seems to slightly raise the risk of developing multiple sclerosis. So when COVID-19 hit, immunologist Dr. Manali Mukherjee wondered if it also triggered autoimmune responses, particularly in the 10 percent of people experiencing long-term symptoms that are shared with autoimmune diseases.The McMaster University professor suspected that hyper-inflammation early in the infection produced rogue antibodies that persisted long after the illness onset. To test her hypothesis, she led a study that tested blood samples from 106 post-COVID patients, recruited between August 2020 and September 2021 at hospitals in Vancouver and Hamilton, and followed them for one year. Published this fall, the research identified two abnormal antibodies (autoantibodies) in up to 30 percent of patients a year after infection. Just because you have autoantibodies doesnt mean you have an autoimmune disease, she cautions. But we always consider that it might develop into an autoimmune disease. For that reason, she advises anyone diagnosed with COVID symptoms lasting more than 12 months to get their autoantibodies tested, either through a GP or a rheumatologist.Now, Mukherjee is leading a longitudinal research study that will follow 120 diagnosed long-haulers for more than a year, in part to answer the question of who develops autoimmune problems after COVID and why. The study will also look at whether the severity of long-haul COVID is related to autoimmune responses triggered by the virus and whether vaccination impacts the severity of long-haul COVID symptoms.The answers to these questions are needed to both treat patients and manage healthcare systems. The problem with long COVID, says Mukherjee, is the sheer number of people who have been affected and the magnitude of it. Caitlin Crawshaw