Immunity to the novel coronavirus may last eight months or longer, according to a new study authored by respected scientists at leading labs, which found that individuals who recovered from the coronavirus developed “robust” levels of B cells and T cells (necessary for fighting off the virus) and “these cells may persist in the body for a very, very long time.”
Researchers collected blood samples from 185 patients between the ages of 19 to 81 who had tested positive for the coronavirus (SARS-CoV-2) early in the pandemic and discovered that most had enough immune cells to combat the virus and prevent reinfection.
In addition, these antibodies were “durable,” showing remarkably slow rates of decline that were consistent with many years, and potentially even decades, of protection.
Although the study is a preprint that has not yet been peer-reviewed, the New York Times refers to it as “the most comprehensive and long-ranging study of immune memory to the coronavirus to date.”
“That amount of memory would likely prevent the vast majority of people from getting hospitalized disease, severe disease, for many years,” said Shane Crotty, a virologist at the La Jolla Institute of Immunology.
According to New York Times reporter Apoorva Mandavilli, the vast majority of individuals (more than 90%) who had been infected with the coronavirus will be “protected from reinfections for a very long time,” and vaccines (“which generally provide stronger, longer-lasting protection”) could produce an even longer duration of immunity. “We probably will not need to vaccinate people every year as we had feared,” writes Mandavilli. The novel coronavirus may be “terminated fast enough that not only are you not experiencing any symptoms, but you are not infectious,” said Dr. Alessandro Sette, an immunologist at the La Jolla Institute of Immunology and co-author of the study. The Times report notes that scientists recently discovered that survivors of SARS, which was also caused by a coronavirus, still carry important immune cells 17 years after being infected. Researchers are also hopeful that studying antibodies may provide a blueprint for developing drugs to prevent or treat Covid-19.
A recent study (also not peer-reviewed) originating from Imperial College London found that immunity to Covid-19 may decline over time, as levels of protective antibodies reportedly fell rapidly after infection. However, according to Deepta Bhattacharya, an immunologist at the University of Arizona, there is some emerging evidence that reinfections with common cold coronaviruses are a “result of viral genetic variations” and those concerns may not be relevant to SARS-CoV-2.
11.3 million. As of Tuesday afternoon, more than 11.3 million people in the United States have tested positive for Covid-19 and at least 247,600 have died.