If you had COVID-19, you got immunity from coronavirus for life: new study
If you've had COVID-19, even if it's mild, you've most likely gained long-term immunity -- probably for life, according to a team of researchers at the Washington University School of Medicine. Theepochtime.
The evidence is compelling and should be welcome and comforting news for a public that is panicking about SARS-CoV-2.
A growing body of evidence shows that there is a long-term immunity.
Initial reports that COVID immunity was short-lived were wrong
Seasonal coronaviruses, some of which cause the common cold, confer only short-term protective immunity, and re-infection occurs six to twelve months after the previous infection. Early data on SARS-CoV-2 also showed that antibody titers declined rapidly in the first months after recovery from COVID-19, leading some to speculate that protective immunity against SARS-CoV-2 may also be short-lived.
Study senior author Ali Ellebedi, Ph.D., an associate professor of pathology and immunology at the Washington University School of Medicine in St. Louis, pointed out that this assumption is wrong, stating in a press release:
“Last fall, there were reports that antibodies rapidly weakened after being infected with the virus that causes COVID-19, and the mainstream media interpreted this as that immunity was short-lived. But this is a misinterpretation of the data. A decrease in antibody levels after an acute infection is normal, but it does not drop to zero.”
The researchers found a biphasic pattern of SARS-CoV-2 antibody concentrations, in which high concentrations of antibodies were found in the acute immune response that occurred during the initial infection.
Antibodies decreased in the first months after infection, as one would expect, then stabilized to about 10-20% of the maximum concentration detected. In a commentary on the study, Andreas Radbruch and Hyun-Dong Chang of the German Rheumatism Research Center in Berlin explained:
“This is consistent with the expectation that 10–20% of plasma cells become memory plasma cells in an acute immune response and is a clear indication of a transition from antibody production by short-lived plasma cells to antibody production by memory plasma cells. . This is not surprising, given that immune memory to many viruses and vaccines persists for decades, if not for life."
When a new infection occurs, cells called plasmablasts produce antibodies, but when the virus is eradicated, longer-lived memory B cells move in to monitor the blood for signs of reinfection.
Bone marrow plasma cells (BMPCs) also exist in the bones, acting as "permanent and important sources of protective antibodies". According to Ellebedi, “The plasma cell is the story of our life in terms of the pathogens we have encountered,” and it is in these long-lived BMPCs that immunity to SARS-CoV-2 resides.
Long-term immunity possible after infection with COVID-19
For the study, blood samples were taken from 77 people who had recovered from COVID-19 about a month after the onset of symptoms; most had mild cases. Additional blood samples were collected three more times at three-month intervals to monitor antibody production. Memory B cells and bone marrow were also collected from some participants.
Anti-SARS-CoV-2 spike protein (S) antibody levels declined rapidly during the first four months after infection and then slowed down over the next seven months. The most exciting part of the study is that at both seven and 11 months after infection, most of the participants had BMPCs that secreted antibodies specific for the spike protein encoded by SARS-CoV-2.
BMPCs have been found in amounts similar to those found in people vaccinated against tetanus or diphtheria, which are thought to confer long-lasting immunity.
“Overall, our data strongly suggest that SARS-CoV-2 infection in humans firmly establishes two pillars of humoral immune memory: long-lived BMPCs and memory B cells,” the researchers noted.
Radbruch and Chang explained that this is perhaps the best evidence of long-term immunity available because this immunological memory is a distinct part of the immune system that is required for long-term protection beyond the initial immune response to the virus:
“During the memory phase of the immune response, B and T cells specific for the virus are at rest, but ready to spring into action if they encounter the virus or the vaccine that represents it again. These memory B and T cells arise from cells activated during the initial immune response. Cells undergo changes in their chromosomal DNA, called epigenetic modifications, that allow them to quickly respond to subsequent signs of infection and trigger responses to eliminate the pathogen. About 25 years ago, it became apparent that plasma cells themselves could become memory cells and could secrete antibodies for long-term protection. Plasma memory cells can be stored in the bone marrow for decades, if not a lifetime.”
You may be interested in: top New York news, stories of our immigrants and helpful tips about life in the Big Apple - read it all on ForumDaily New York.
In addition, it was reported in 2020 that people who recovered from SARS-CoV, a virus that is genetically closely related to SARS-CoV-2 and belongs to the same virus species, maintained significant levels of neutralizing antibodies for at least 17 years after infection. This also suggests that long-term immunity against SARS-CoV-2 should be expected. Ellebedi even said that the protection would probably last "indefinitely":
“These BMPC cells are not dividing. They are immobile, just sit in the bone marrow and secrete antibodies. And they will continue to do so indefinitely."
Read also on ForumDaily:
stdClass Object ([term_id] => 1 [name] => Miscellaneous [taxonomy] => category [slug] => no_theme)Miscellanea
stdClass Object ([term_id] => 10833 [name] => immunity [taxonomy] => post_tag [slug] => immunitet)immunity
stdClass Object ([term_id] => 13992 [name] => Likbez [taxonomy] => category [slug] => poleznaja-informatsija)Educational program
stdClass Object ([term_id] => 28340 [name] => coronavirus [taxonomy] => post_tag [slug] => koronavirus)coronavirus
stdClass Object ([term_id] => 28353 [name] => READ ABOUT CORONAVIRUS [taxonomy] => special [slug] => kitajskij-koronavirus)
Do you want more important and interesting news about life in the USA and immigration to America? Subscribe to our page in Facebook. Choose the "Display Priority" option and read us first. Also, don't forget to subscribe to our РєР ° РЅР ° Р »РІ Telegram - there are many interesting things. And join thousands of readers ForumDaily Woman и ForumDaily New York - there you will find a lot of interesting and positive information.