Although based on a small sample of people (31), the findings of this study seem so strong that the researchers consider it compelling. It still needs to be peer reviewed.
How is this progress?
Taken alone, this study does not constitute a total revolution. But its conclusions come to cross those of previous studies, and to enlighten doctors a little more on the origins of the long Covid, and therefore, potentially, on the means of treating it. Indeed, if the Spike protein is found in the plasma of long Covid patients, this would mean that there persists somewhere in their body a reservoir of active virus and that this virus has found a way to pass into the blood.
The hypothesis of a “virus reservoir” has already been put forward in a study by Stanford University, published in April and May 2022 in several scientific journals. The team of Ami Bhatt, oncologist and geneticist, had then updated “phantom viruses”, or RNA fragments of SARS-CoV-2 not in the respiratory samples (where the virus had disappeared) but in the gut of two-thirds of patients with long Covid up to 7 months after their infection.
In addition, a study by David R. Walt’s team published in the journal Critical Care Exploration in February 2022 also revealed the presence of a SARS-CoV-2 replication reservoir in the digestive system of children. who have suffered a multisystem inflammatory syndrome (MISC) following a Covid infection, even long after the infection. According to the researchers, the virus present in the intestine could then have passed into the blood through a breach in the gastrointestinal barrier, made porous by inflammation.
At the same time, another study from the University of Innsbruck, published in May 2022 in the journal Gastroenterology, revealed that fragments of the SARS-CoV-2 virus were still present after six months in the intestinal mucosa of the majority of patients. with chronic inflammatory bowel disease (IBD). Affected patients suffered from long Covid symptoms.
What are the current conclusions?
Taken collectively, these results suggest that the symptoms of long Covid are due to the persistence of SARS-CoV-2 in the intestine, which would also allow the virus to pass into the blood.
The presence of Spike protein in the plasma of patients with long Covid, highlighted by the team of Harvard researchers, again supports this hypothesis. If it is confirmed, the hope of a more reliable diagnosis is emerging, because the long Covid could be identified by a simple blood test to measure the presence of this protein. Treatment strategies could also be accelerated.