A new study suggests recipients of Moderna’s COVID-19 vaccine may be more likely to suffer repeated infections, perhaps indefinitely.
The study, still in preprint, found participants in Moderna’s adult trial who received the vaccine, and later were exposed to the virus, did not generate antibodies to a key component of the virus as often as did those in the placebo group.
The authors’ findings, which are corroborated by U.K. data that demonstrate the rates of infection are significantly higher in the vaccinated, suggest Moderna knew of this safety signal in 2020 when the vaccine maker was conducting its trials.
The authors of “Anti-nucleocapsid antibodies following SARS-CoV-2 infection in the blinded phase of the mRNA-1273 Covid-19 vaccine efficacy clinical trial“ wrote:
“Among participants with PCR-confirmed Covid-19 illness, seroconversion to anti-N Abs at a median follow up of 53 days post diagnosis occurred in 21/52 (40%) of the mRNA-1273 vaccine recipients vs. 605/648 (93%) of the placebo recipients (p < 0.001).”
Vaccinated participants in the trial who developed breakthrough COVID-19 — meaning they received a positive PCR test — mounted an antibody response to the nucleocapsid portion of the SARS-CoV-2 virus less often than did placebo recipients who tested positive for the virus.
The difference was statistically significant, leading the authors to conclude:
“Vaccination status should be considered when interpreting seroprevalence and seropositivity data based solely on anti-N Ab testing.
“As a marker of recent infection, anti-N Abs may have lower sensitivity in mRNA-1273-vaccinated persons who become infected.”
In other words, the authors found that using the presence of anti-nucleocapsid (anti-N) antibodies to determine whether a person was exposed to SARS-CoV-2 will miss some infections. Thus, the sensitivity of this kind of test, when applied to vaccinated individuals, is not ideal.
However, there are more important implications of these findings, as Igor Chudov and others were quick to recognize.
Specifically, the study implies that the reduced ability of a vaccinated individual to produce antibodies to other portions of the virus may lead to a greater risk of future infections in the vaccinated compared to the unvaccinated.
It is important to note that this is not just another argument for the superiority of natural immunity.
Rather, this is evidence suggesting that even after a vaccinated person has a breakthrough infection, that individual still does not acquire the same level of protection against subsequent exposures that an unvaccinated person acquires.
This is a troubling finding, and something investigators conducting the Moderna vaccine trial likely knew in 2020.
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