Plasma from COVID-19 convalescents does not help other patients

One of the treatments for coronavirus infection is blood plasma transfusion from another person who is recovering from COVID-19 or has just recovered. It is assumed that the patient should be saved by foreign antibodies. Immunity produces them against any pathogen, and against coronavirus too, and since a person was able to defeat the disease, it means that his immune cells were able to select the right antibodies and synthesized them in large quantities. It remains to take blood from the convalescent, clear it of erythrocytes (to avoid clotting) and some other components, and transfuse it to the patient. This method is recommended for seriously ill patients who are already seriously threatened by an artificial respiration apparatus (IVL).

However, researchers from McMaster University, The University of Montreal and other research centers have come to the conclusion that the benefits of convalescent plasma are greatly exaggerated. In an article in Nature Medicine they describe clinical observations of 940 covid patients from 72 hospitals in Canada, the United States and Brazil. Some were transfused with plasma, some were treated with other methods, but both were almost equally likely to be on mechanical ventilation and died with equal probability.

The authors also write that the transfused plasma was very different in the quantity and quality of anti-coronavirus antibodies. And, paradoxically, if the antibodies in the donor plasma were not very suitable for the coronavirus, or the concentration of antibodies was low, then the patient’s condition was likely to worsen. The authors of the work explain this by the fact that less successful donor antibodies do not help, but interfere with the patient’s immunity; Obviously, something similar happens when there are relatively few antibodies in the transfused plasma.

This can explain the results of other observations that indicate the benefits of donor plasma: according to the researchers, the benefits in such cases are visible only when plasma with a high concentration of adequate antibodies is compared with plasma with a low concentration of antibodies or with not very good antibodies. If we compare “good” plasma with other methods of therapy, then, as it was said, there is no statistically significant advantage of plasma. (In this case, even “good” plasma is fraught with allergic complications.)

Obviously, the new data will be double-checked, but so far the researchers are confident enough in them to discourage the use of donor plasma in the treatment of severe cases of COVID-19.

Source: Автономная некоммерческая организация "Редакция журнала «Наука и жизнь»" by

*The article has been translated based on the content of Автономная некоммерческая организация "Редакция журнала «Наука и жизнь»" by If there is any problem regarding the content, copyright, please leave a report below the article. We will try to process as quickly as possible to protect the rights of the author. Thank you very much!

*We just want readers to access information more quickly and easily with other multilingual content, instead of information only available in a certain language.

*We always respect the copyright of the content of the author and always include the original link of the source article.If the author disagrees, just leave the report below the article, the article will be edited or deleted at the request of the author. Thanks very much! Best regards!