Herd immunity good news: new studies show that coronavirus immunity can last for more than 6 months

Some stories Unlucky patient infected with COVID-19 twice Sent the world to tail spin fear It Immunity to the virus may not last.. However, there is encouraging news in the new research report.

Preprint Survey BioRxiv, published online on Monday, claims that people who have acquired immunity from SARS-CoV-2, the virus that caused COVID-19 disease, may be able to maintain immunity for more than 6 months. doing.on the other hand Previous research We have focused on aspects of how the human immune system responds to viruses, such as analyzing the protein components of the immune system and studying how antibodies react to viruses. In this new study, we studied many elements of immune memory, including B cells. Cells and antibodies.

The authors say that “immune memory is a source of long-term defensive immunity, but scientists know little about’, so about defensive immunity based on quantifying the regions of the immune system components they studied. We cannot draw conclusions directly. ” Mechanism of protective immunity against human SARS-CoV-2 or COVID-19 “.

With this warning, the authors found that approximately 90% of subjects developed immune memory “consisting of at least three immunological compartments” more than five months after their first symptoms, resulting in the last to COVID-19. He claimed that he had a reason to believe in his immunity. It may be possible for most people.

Of particular note was the fact that memory B cells were found in almost all cases of COVID-19 and appear to increase over time. “B-cell memory for some other infections has been observed to be long-lived, including more than 60 years after smallpox vaccination or more than 90 years after influenza infection,” the study authors write. I have. B cells are a type of white blood cell that matures in the bone marrow in mammals.

This study has not been peer-reviewed or published in scientific journals, but it is hopeful because it was co-authored by many scientists at Mount Sinai School of Medicine in New York and the Lahoya Institute for Immunology. University of California, San Diego. 185 adults between the ages of 19 and 81 (mostly recovered from mild symptoms of the disease) were examined by collecting blood samples from various points in time after the initial symptoms. In some cases, blood samples were taken at least 6 months after the patient first showed symptoms.

Previous studies have been less promising regarding the prospect of long-term immunity from COVID-19. A July Theses Published on a preprint server, medRxiv surveys blood samples taken over the first three months of diagnosis from 65 people who are positive for coronavirus and whose symptoms range from asymptomatic to severe. Did. Over time, those scientists found that patients saw a decrease in antibodies that could neutralize the virus (nAbs).

“A wide range of SARS-CoV-2 neutralizing antibody (nAb) titers have been reported after infection, depending on the time since infection and the severity of the disease,” the study explained. “Further knowledge of the magnitude, timing, and longevity of nAb responses after SARS-CoV-2 infection may be achieved by nAb in disease elimination and protection from reinfection (also called renewal or second-wave infection). It is essential to understand a role. “

another SurveyPublished in the scientific journal Nature Medicine in September, helps to investigate people infected with four seasonal coronaviruses that can cause respiratory infections and predict the immunity of the new coronavirus. I guessed. The study suggests that “spontaneous reinfection occurs in all four seasonal coronaviruses and is a common feature of all human coronaviruses, including SARS-CoV-2. Occurred most frequently 12 months after infection and had short-lived protective immunity. “