Messenger RNA sequences from the Pfizer and Moderna COVID-19 vaccines were found in the blood of multiple individuals weeks after vaccination, according to a new study.
Researchers in Denmark analyzed samples from the vaccinated and detected partial or even full sequences of the messenger RNA (mRNA) following vaccination. The sequences were found as late as 28 days after vaccination, or the longest time period the study analyzed.
The findings mean that the mRNA, which is situated in lipid nanoparticles for deliverance into the body, lingers for much longer than authorities in the United States and elsewhere acknowledge.
Henrik Westh, a professor of clinical microbiology at the University of Copenhagen, and co-authors of the new study described being surprised by the findings.
“We surprisingly found fragments of COVID-19 vaccine mRNA up to 28 days postvaccination in blood from chronic HCV patients vaccinated with mRNA vaccines from both Pfizer-BioNTech and Moderna,” they wrote.
The study featured taking samples from 108 vaccinated people with chronic hepatitis C virus, or HCV, and examining them for up to 28 days after vaccination.
Ten of the samples, or 9.3 percent, had partial or full sequences of the mRNA sequence.
The vaccines deliver mRNA inside lipid nanoparticles.
The researchers said that the detected mRNA was likely still inside the nanoparticles, which “have been slowly released from the injection site either directly to the blood or through the lymph system.” Without the nanoparticles, the mRNA “would rapidly degrade.”
They claimed that the new data “does not in any way change the conclusion that both mRNA vaccines are safe and effective.”
The researchers also said the mRNA lingering in the blood “allows pro-longed spike protein production giving an advantage for a continuous immune response in some persons.”
If true, that would amount to chronic low-level boosting, which would exacerbate immune imprinting, or focusing one’s body on the outdated strains the vaccines target, according to Malone, who helped develop the mRNA technology.
Malone said the difficulty in identifying mRNA specifically from the vaccines, particularly as time goes on, means there may have been RNA from the vaccines in the blood of some of the other samples.
Westh, Pfizer, and Moderna did not respond to a request for comment.
The papers highlight how “we really don’t know how long this RNA persists,” Malone said. “The true implications of all of this is that the assumption that adverse events occurring later than two to three weeks cannot be associated with the drug product once again is clearly false.”
The mRNA delivers instructions to the body to produce the spike protein, which is meant to protect people against COVID-19.
Experts have raised concerns that the circulating spike protein is toxic and contributes to myocarditis, a form of heart inflammation caused by the vaccines, and other adverse events following vaccination.