4% 'healthy' blood donors in Lucknow found with Covid antibodies

LUCKNOW: A study on 'antibodies among blood donors', conducted by the Transfusion Medicine department of the King George's Medical University (KGMU) has revealed that a section of the people in the city contracted the novel coronavirus infection but recovered without even knowing they were carrying the virus.
The tests done during the study found that 46 (3.7%) out of the total 1,235 'healthy' persons who donated blood in the department in the past two weeks, had antibodies against novel coronavirus. This means that these people were infected at some point of time in the past but remained asymptomatic throughout the period of the disease and got cured by developing antibodies that fight against the pathogen, said doctors involved in the research.
These blood donors, said researchers, could not recall having any Covid-19 symptoms in the past and had not undergone any test for Covid-19 diagnosis. Such cases have been reported elsewhere in the world, but evidence of it has been found in Lucknow for the first time, they added. The department can now extract plasma from the blood donated by these donors for convalescent plasma therapy of Covid-19 patients.
"All the 1,235 blood donors were examined and found healthy. All of them when asked about Covid-19 history told us that they neither had any symptoms of the disease in the past, nor undergone tests for the novel coronavirus infection. The blood samples of all the donors tested in the antibody machine which can track immunoglobulin G-IgG - a protective antibody that develops in most patients at around two weeks after infection and remains in the blood even after recovery for sometime. Of total, 46 were found to be having IgG,” explained Prof Tulika Chandra, head of Transfusion Medicine department.
She also said that the research is at the initial stage, hence nothing can be said with certainty about the population developing herd immunity, for which around 50%-60% population should have antibodies.
Prof Chandra admitted that as the said 46 people were unaware about their infection status, they may have transmitted infection to others. “However, these people can now make up by donating plasma. We have already extracted plasma from the blood donated by them. Now we will counsel them to donate more for the bank we have created to provide convalescent plasma therapy to needy patients, she added.