It did not say whether or not these people with covid/long covid who were tested had been vaccinated or not. That seems to me that it would make a big difference as to what would be found in the blood tests. I would be very curious to have people evaluated that had covid but were not vaccinated. I (and my immediate family)are in that category and I see different seemingly long term effects after our covid experience. Nothing major but a lot of little idiosyncrasies.