The World Health Organization acknowledged in its scientific brief on COVID-19 Natural Immunity dated May 10, 2021 (1) that:
“Natural infection may provide similar protection against symptomatic disease as vaccination.”
It’s time for the Centers for Disease Control (CDC) to acknowledge the same.
It’s time to look at the scientific data showing that natural immunity from prior COVID-19 infection is not only as protective, but may actually be MORE protective than a vaccine, and that prior infection may also increase the risk for serious adverse vaccine reactions.
It’s time to make a science-based policy shift and rethink the CDC’s current recommendation that all eligible individuals should get a vaccine, regardless of whether they’ve already had COVID-19.
Antibodies, Memory B Cells, Memory T Cells & Long-Lived Plasma Cells
Immunity against most human coronaviruses that cause the common cold (hCoV-OC43, hCoV-229E, hCoV-NL63 and hCoV-HKU-1) may be short lived and not last longer than a year. (2)
But SARS-CoV-2 is NOT like most other human coronaviruses.
SARS-CoV-2, the human coronavirus that causes COVID-19, is much more closely related to MERS-CoV and SARS-CoV-1, which caused Middle East Respiratory Syndrome (MERS) in 2009 and Severe Acute Respiratory Syndrome (SARS) in 2003, respectively. In the case of MERS and SARS-CoV-1, antibodies have been detected years after initial infection, and immunity is thought to possibly be lifelong. (3,4,5)
90-99% of people who recover from COVID-19 develop detectable neutralizing antibodies. (1) SARS-Cov-2 antibodies from COVID-19 infection are detectable for at least 6-12 months after initial infection. (6,7,8) As time passes from the beginning of the pandemic, and antibodies in those with prior infection continue to be followed, we will likely see that antibodies endure long-term as they do for SARS and MERS.
And while SARS-CoV-2-specific IgG antibodies may wane over time, as is typical for most viral infections, this is not necessarily a sign of decreasing immunity. Increasing evidence (9,10,11,12,13,14,15) points to long-lasting B-cell and T-cell immunity and long-lived plasma cells after SARS-CoV-2 infection, even mild infection – which may confer lifelong immunity.
Memory lymphocytes produced after SARS-CoV-2 infection exhibit potent antiviral immunity. (12) When re-exposed to SARS-CoV-2 antigens, memory lymphocytes have multiple strategies to protect against reinfection. Memory CD4+ T cells secrete an antiviral cytokine, IFN-gamma. Memory CD8+ T cells can kill virus-infected cells directly. And memory B cells differentiate into IgG+ antibody-secreting plasmablasts. This memory immune response on re-exposure is capable of neutralizing the virus and preventing reinfection.
COVID-19 infection also induces lasting bone marrow plasma antibody protection. As antibody production wanes after initial infection, a small population of antibody-producing cells called “long-lived plasma cells” migrate to our bone marrow and continually secrete low levels of antibodies. Long-lived plasma cells were identified in patients with even mild COVID-19 disease, and the authors speculate that even asymptomatic people have long-term protection due to these long-lived plasma cells. (16)
Prior SARS-Cov-2 infection induces Memory B cell, Memory T cell and Long-lived Plasma Cell protection that confers LONG-TERM and possibly LIFELONG IMMUNITY.
Reinfection Rates are Very Low
In real life, reinfection rates are very low. While reinfection with SARS-CoV-2 can occur, six large studies from the US (17), UK (18), Denmark (19), Austria (20), Qatar (21), and US Marines (22), found that infection with SARS-CoV-2 provides 82-95% protection from reinfection for at least 7 months. (23,24)