Repeated administration of mRNA COVID-19 boosters may impair the immune system response in immune-compromised individuals, raising questions about whether giving multiple vaccine doses cause more harm than good.
In a review published on Jan. 27 in Clinical and Experimental Medicine, scientist Alberto Boretti found repeated COVID-19 booster doses may increase the likelihood of experiencing SARS-CoV-2 infection and other pathologies. Additionally, receiving frequent vaccination may result in much higher levels of IgG4 antibodies and inhibit the activation of white blood cells that help protect the body from infections and cancer.
Immunoglobulins, or antibodies, are proteins made by white blood cells called B cells. Although IgG4 antibodies have a protective effect up to a certain level, a growing body of evidence suggests that abnormally high levels from repeated vaccination may cause IgG4-related disease involving multiorgan inflammation, autoimmune diseases, rapid onset cancers, and autoimmune myocarditis.
“While booster doses have been recommended to enhance and extend immunity, especially in the face of emerging variants, this recommendation is not based on proven efficacy, and the side effects have been neglected,” Dr. Boretti wrote.
To determine whether mRNA vaccine boosters impair the immune response in immunocompromised individuals, Dr. Boretti conducted a literature review using the Google Scholar database.
He found very few long-term studies that evaluate the safety and efficacy of repeated booster vaccination in immune-compromised individuals, especially with a continuously evolving virus. Instead, he found evidence that multiple mRNA vaccine boosters impair the activation of CD4+ and CD8+ T cells. These cells make up the majority of T cells that protect the body by destroying harmful pathogens and helping it respond to infections, allergens, and tumors. CD4+ T cells are especially critical because they activate other immune cells, coordinate the immune response against infections, and help B cells create antibodies.
Impairment of CD4+ T cells can result in reduced antibody production and compromise the body’s ability to mount an effective humoral immune response against pathogens, increasing susceptibility to opportunistic infections caused by pathogens that do not typically cause disease in individuals with healthy immune systems.
CD8+ T cells are vital to cell-mediated immunity because they recognize and eliminate infected or abnormal cells and help prevent excessive inflammation. Impaired activation of CD8+ T cells allows infections or tumor growth to persist.
Even though the author found that the harm of repeated vaccination may outweigh the benefit, the immunocompromised are the first group to receive additional vaccine doses.
Studies Show Repeated Boosters May Harm Immune Response
A 2023 study published in Vaccines showed that repeated COVID-19 mRNA vaccination increases the level of IgG4, weakening the immune system and potentially making people more susceptible to life-threatening conditions such as cancer.
A February 2022 Lancet study showed the effectiveness of COVID-19 vaccines progressively waned over time and that vaccinated individuals had lower immune function eight months after receiving their initial two vaccine doses than unvaccinated individuals. These findings were more prominent in older adults and individuals with preexisting conditions.
Some experts are seeing a concerning rise in aggressive, rapid-onset cancers resistant to treatment following vaccination. One theory is that the shift of IgG4 caused by repeated mRNA vaccination creates a tolerance for spike protein and impairs the production of the antibodies IgG1 and IgG3 and cancer surveillance.
According to Boretti’s paper, other studies have shown that the immune system may be negatively impacted by the persistence of spike protein following vaccination, inflammatory lipid nanoparticles containing modified RNA that travel from the injection site, unintended consequences of spike protein antibodies, and the replacement of uracil in the genetic code with N1-methyl-pseudouridine.
Boosters Recommended Despite Excluding Immunocompromised in Vaccine Trials
Pharmaceutical companies only included healthy individuals in their initial COVID-19 vaccine clinical trials, and the only immunocompromised subgroups included in phase 3 vaccine trials were those with chronic, stable HIV infection, hepatitis B, or hepatitis C. Yet immunocompromised individuals were the first group authorized to receive booster shots.
Current CDC guidance recommends that people aged 6 months and older who are moderately or severely immunocompromised and received their COVID-19 vaccines before Sept. 12, 2023, receive one or two doses of an updated vaccine, depending on the number they’ve previously received. Before Sept. 12, if an immunocompromised person followed the CDC recommendations, they would have already received at least five vaccine doses.
To date, there are no clinical trials showing whether it is safe for someone with a compromised immune system to receive multiple vaccine doses of the newly formulated booster or the potential effects of combining current COVID-19 boosters with previous bivalent and monovalent vaccines. Instead, the U.S. health agencies have adopted a “the more the merrier” mentality.
