A study published in the journal Lancet, revealed that antibody levels and the duration of immunity may differ in Covid-19 survivors.

The study is titled Dynamics of SARS-CoV-2 neutralizing antibody responses and duration of immunity: A Longitudinal Study.

For the study, the researchers analysed neutralising antibodies in patients up to six months after the onset of symptoms.

Dr. Ravindra Mehta, senior consultant and head of pulmonology and interventional pulmonology at Apollo Speciality Hospitals, said that in some people, antibody levels dropped fast, but lasted longer in others, Indian Express reported.

He added that in some patients, levels fluctuated and in others, antibodies were present for up to six months.

“Persistence of neutralizing antibodies was associated with disease severity and sustained level of pro-inflammatory cytokines, chemokines and growth factor,” the study noted.

“This means that those who had a severe infection, with inflammation caused by cytokine storms, were found to have antibodies up to six months,” Dr. Mehta said. “In people who had a milder infection or were asymptomatic, antibody levels were low. However, T-cell immunity, which is long-term cell immunity, was present in people despite neutralizing antibodies going away,” he further added.

According to the study, the rate of antibody levels waning suggests reinfection is likely during later waves, limiting the viability of a herd immunity strategy before an effective vaccine.

The researchers concluded that patients who had persistent antibodies were older and had more comorbidities, including hypertension.

Related Topics
comment COMMENT NOW