Antibody levels in the blood of Covid-19 patients drop rapidly during the weeks after their bodies have cleared the novel coronavirus, and symptoms have subsided, according to a study.
In the absence of approved, effective treatments for Covid-19, some hospitals have been treating patients with severe symptoms with blood plasma from recovering patients.
If convalescent plasma is ultimately shown to have a clear benefit, the new study published in the journal mBio concluded that it needs to be collected during a specific window of time after recovery.
However, recovering patients can't donate blood until at least 14 days after symptoms have subsided, to give the body time to clear viral particles.
"We don't want to transfuse the virus, just transfuse the antibodies," said Andres Finzi at the University of Montreal in Canada. "But at the same time, our work shows that the capacity of the plasma to neutralise viral particles is going down during those first weeks," Finzi said.
The spike protein of SARS-CoV-2 plays a crucial role in helping the virus grab and invade host cells.
Findings from an earlier cross-sectional study by Finzi's group, involving more than 100 patients, suggested that the ability of plasma to neutralise the virus decreased significantly between 3 and 6 weeks after symptom onset.
Source: PTI
