In February 2021, the CDC stated that currently available mRNA COVID-19 vaccines would likely offer fully vaccinated individuals at least three months of vaccine-acquired immunity. In their quarantine guidance released on February 11, 2021, the CDC stated that fully vaccinated people (those who had received two doses of COVID-19 vaccine) who were exposed to SARS-CoV-2 through close contact would not be required to quarantine as long as vaccination had occurred within three months and they remained asymptomatic.
However, in March 2021 the CDC’s website stated that it was not unknown how effective, or for what length of time the experimental COVID-19 vaccines would provide immunity against COVID 19 illness. The website also reported that it was also not known how effective the vaccine would be in mediating the severity of illness, should the vaccine fail to prevent COVID-19.
On April 27, 2021, fully vaccinated individuals were still being told that they must stay at least 6 feet apart from others; wear masks in certain outdoor crowded public settings and indoor public settings; and when in gatherings with unvaccinated individuals. Vaccinated individuals were also being told to take precautions when visiting unvaccinated individuals who were at an increased risk for severe COVID-19 disease and to be vigilant about symptoms and get tested when they occur. The CDC, however, stated that vaccinated individuals could travel domestically and internationally without quarantining, and that pre- and post- travel testing was not required, unless the international destination required it. Persons entering the U.S., however, were still required to show a negative COVID-19 test result before boarding a flight and testing was still advised 3-5 days following international travel.
In May 2021, the CDC announced that fully vaccinated individuals could resume activities without masking or physically distancing, except where required by law, workplace or local requirements. Additionally, they could travel domestically without testing or self-quarantine, and travel internationally without testing unless their destination required it, and would not be required to self-quarantine on return. Vaccinated persons exposed to someone with SARS-CoV-2 were also advised that they would not need to self-quarantine or test unless symptomatic.
Since emergency use of the experimental COVID-19 vaccines was authorized by the FDA in December 2020, there have been multiple reports of fully vaccinated individuals testing positive for SARS-CoV-2.
In early 2021, the CDC began reporting cases, hospitalizations, and deaths among fully vaccinated individuals. By April 30, 2021, the CDC reported 10,262 cases, 995 hospitalizations, and 160 deaths among persons who had been fully vaccinated, with the CDC acknowledging that the actually number of breakthrough cases were likely much higher due to the passive and voluntary system of reporting.
In late April 2021, the CDC announced that it was only going to be reporting the number of breakthrough cases that resulted in hospitalization and death “to help maximize the quality of the data collected on cases of greatest clinical and public health importance.” As a result, the public would not be made aware of the actual number of reported breakthrough cases occurring fully vaccinated individuals.
On July 27, 2021, the CDC issued a health alert and reported that fully vaccinated individuals could still become infected and be capable of transmitting the virus to others. Public health officials reported that the SARS-CoV-2 variants currently circulating in the U.S., especially the Delta variant, were highly transmissible and increasing the rate of infections. The CDC also recommended that all persons, including fully vaccinated individuals, wear masks in public indoor spaces in communities with high or substantial transmission rates.
While this health alert reported that most COVID-19 cases, hospitalizations, and deaths were occurring in unvaccinated individuals, data released from an outbreak in Massachusetts reported that 74 percent of cases had occurred in fully vaccinated individuals. Additionally, four of the five hospitalizations reported during this study occurred in fully vaccinated individuals.
A study published in Science using data from the U.S. Veterans Health Administration published in early November 2021 reported that after six months, the effectiveness of all three available COVID-19 vaccines had significantly waned. The Moderna COVID-19 vaccine effectiveness decreased from an 89.2 percent effectiveness in March 2021 to a 58 percent effectiveness by September 2021. The Pfizer-BioNTech COVID-19 vaccine was reported to have decreased in effectiveness from 86.9 percent in March 2021 to 43.3 percent by September 2021. The Janssen/Johnson & Johnson COVID-19 vaccine decreased from an effectiveness of 86.4 percent in March 2021 to only a 13.1 percent effectiveness by September 2021.
In the summer of 2023, the Informed Consent Action Network (ICAN), a non-profit dedicated to eradicating man-made disease, obtained FDA email communications pertaining to the effectiveness of COVID-19 vaccines in the first half of 2021 through a Freedom of Information Act (FOIA) request. These emails revealed that health regulators were aware that a data analysis compiled on 20 million Medicare beneficiaries had found that COVID-19 vaccine effectiveness waned rapidly within 5-6 months post vaccination for both infection and hospitalization in persons 65 years and older. The emails also reported that health officials knew that similar trends were emerging in the data among seniors who were 3-4 months post-vaccination.
This data, however, was not revealed to the public during the August 2021 ACIP and September 2021 VRBPAC meetings convened to review and make recommendations on COVID-19 vaccine booster doses. Instead, data from the CDC’s COVID-NET, which showed the vaccine effectiveness against hospitalization to be 80 percent during the delta variant surge, was presented. Additional data, including studies on the Pfizer vaccine effectiveness in Israel, which showed the vaccine to be between 39 and 84 percent effective against infection and between 75 and 95 percent against hospitalization were also presented in lieu of the Medicare data analysis.
Efficacy of the original COVID-19 mRNA vaccines
In February 2021, a study questioning the efficacy of COVID-19 vaccines expressed concerns regarding the absence of data on absolute risk reduction in the Pfizer-BioNTech and Moderna COVID-19 vaccine clinical trials.
According to this study, the Pfizer-BioNTech COVID-19 vaccine showed an absolute risk reduction of 0.7 percent (95% CI 0.59% to 0.83%) and the study author, Ronald Brown, reported that 142 people (95% CI 122 to 170) would need to be vaccinated to prevent one case of COVID-19. The Moderna COVID-19 vaccine showed an absolute risk reduction of 1.1 percent (95% CI 0.97% to 1.32%) and 88 individuals (95% CI 76 to 104) would need to be vaccinated to prevent one COVID-19 case.
Brown concluded by noting that:
“A critical appraisal of phase III clinical trial data for the Pfizer/BioNTech vaccine BNT162b2 and Moderna vaccine mRNA-1273 shows that absolute risk reduction measures are very much lower than the reported relative risk reduction measures. Yet, the manufacturers failed to report absolute risk reduction measures in publicly released documents. As well, the U.S FDA Advisory Committee (VRBPAC) did not follow FDA published guidelines for communicating risks and benefits to the public, and the committee failed to report absolute risk reduction measures in authorizing the BNT162b2 and mRNA-1273 vaccines for emergency use. Such examples of outcome reporting bias mislead and distort the public’s interpretation of COVID-19 mRNA vaccine efficacy and violate the ethical and legal obligations of informed consent.”
