New COVID-19 Research Raises Optimism on Post-infection Immunity

Shane Crotty who led the team of researchers says that long lasting antibody levels and immune memory cells could potentially lessen the severity of a re-infection.

Nature could prove to be man's best ally in slowing down, or actually averting the devastation to humanity potentially posed that the coronavirus.  Researchers at the La Jolla Institute of Immunology in California have found that natural immunity triggered by COVID-19 infection could last longer than previously thought.

Until now it was unclear how long immunity after infection can last but researchers looked at immunity to SARS- COV- 2, the virus that causes COVID-19  in 185 people, 45 of  whom were more than six months past initial infection.  Majority of the people studied had mild infection and had not required hospitalization.

According to the findings published in the  Biorxiv medical journal, researchers looked at four elements of the immune response including antibody levels, memory B cells that remember the pathogen and when exposed to it again triggers a rapid antibody response. They also looked at T cells that kill infected cells. They found people with COVID-19 seemed to have fairly robust and long lasting immune responses. 

The researchers also found that antibodies lasted well, with a small drop in levels at 6-8months after infection. They also found that T cells levels reduced slightly and B cells increased.

Shane Crotty who led the team of researchers, says that long lasting antibody levels and immune memory cells could potentially lessen the severity of a re-infection. 

Understanding immune memory to the virus is critical in improving diagnostics and vaccines and for assessing the likely future course of the pandemic, however researchers have not yet found conclusive data about the immunity triggered by SARS- COV – 2 even as a lot of studies are going on in many parts of the World. 

The new findings, though exciting, have not yet been peer reviewed.  However, the immunity seen so far by the researchers gives scientists some elbow room to work more on vaccines and cures as the bodies of previously infected persons provide some breathing space to the different teams working worldwide to beat the coronavirus.