A notable aspect of the Covid-19 pandemic has been how often unpopular scientific ideas, from the theory of the virus’s escape from the Chinese laboratory to the effectiveness of masks, were initially rejected, even ridiculed, only to re-emerge later in mainstream thinking. Differences of opinion have sometimes been rooted in disagreement over the underlying science. But the most common motivation was a political one.
The next turnaround of common thinking may be imminent. Some scientists have raised concerns that the safety risks of Covid-19 vaccines have been underestimated. But the policy of mass vaccination has relegated their concerns to the periphery of scientific thinking. At the moment.
Historically, the safety of drugs – including vaccines – is often not fully evaluated until they are distributed in large numbers. Examples include rofecoxib (Vioxx), a pain reliever that increased the risk of heart attack and stroke; antidepressants that appeared to increase suicide attempts among young adults; and a flu vaccine used in the 2009-10 swine flu outbreak that was suspected of causing febrile seizures and narcolepsy in children. Evidence from the real world is invaluable, as clinical trials often enroll patients who are not representative of the general population. We learn more about drug safety from real-world evidence and can adjust clinical recommendations to balance risks and benefits.
The Vaccine Adverse Event Reporting System, or Vaers, which is administered by the Centers for Disease Control and Prevention and the Food and Drug Administration, is a database that allows Americans to document adverse events that occur after receiving a vaccine. The FDA and CDC say the database is not designed to determine whether the events were caused by a vaccine. This is true. But the data can still be evaluated, taking into account their strengths and weaknesses, and that’s what the CDC and the FDA say they do.
Vaers data for Covid-19 vaccines show an interesting pattern. Among the 310 million Covid-19 vaccines administered, several adverse events are reported in high rates in the days immediately following vaccination, only to drop precipitously thereafter. It is possible that some of these adverse events would have occurred anyway. This pattern may be partly attributable to the tendency to report more events that occur soon after vaccination.
The database cannot tell what would have happened in the absence of vaccination. However, the strong clustering of some adverse events soon after vaccination is concerning, and the silence around these potential signs of harm reflects the policy surrounding Covid-19 vaccines. Stigmatizing such concerns is bad for scientific integrity and could harm patients.
According to the data taken directly from Vaers, there are four serious adverse events that follow this parable: low platelets (thrombocytopenia); non-infectious myocarditis, or inflammation of the heart, especially for those under 30; deep vein thrombosis; and death. Vaers records 321 cases of myocarditis within five days of vaccination, which drop to nearly zero within 10 days. Previous research has shown that only a fraction of adverse events are reported, so the true number of cases is almost certainly higher. This tendency to underrepresentation is consistent with our clinical experience.
Analyzes to confirm or reject these findings should be performed using large datasets held by health insurance companies and health organizations. The CDC and the FDA are certainly aware of these data patterns, but neither agency has recognized that trend.
The implication is that the risks of a Covid-19 vaccine may outweigh the benefits for some low-risk populations, such as children, young adults and people who have recovered from Covid-19. This is especially true in regions with low levels of community spread, as the likelihood of disease depends on the risk of exposure.
And while you’ll never learn from listening to public health officials, not a single published study has shown that patients with a previous infection benefit from vaccination against Covid-19. That this is not readily acknowledged by the CDC or Anthony Fauci is an indication of how deeply pandemic politics is steeped in science.
There are, however, signs of life for scientific honesty. In May, the Norwegian Medicines Agency reviewed the files of the first 100 reported deaths of nursing home residents who received Pfizer vaccine. The agency concluded that the vaccine “probably” contributed to the deaths of 10 of these residents through side effects such as fever and diarrhea, and “perhaps” contributed to the deaths of 26 others. But this kind of intellectual honesty is rare. And it’s rare for any vaccine being linked to deaths, so this unusual development for mRNA vaccines deserves further investigation.
That to recover scientific honesty will be an uphill race in the United States. Anti-Trump politics in the spring of 2020 resulted in social media censorship. Reports often lack intellectual curiosity about the adequacy of public health guidelines, or do not explain why a noisy minority of scientists strongly disagree with prevailing views. There have been scientists siding in favor of or against Covid-19 therapies and who at the same time maintained financial relationships with pharmaceutical companies and their foundational benefactors.
Public health authorities are making a mistake and jeopardizing the public’s confidence in not being willing to admit the possibility of harm resulting from some side effects of vaccines. There will be lasting consequences from mixing political partisanship and science in the midst of handling a public health crisis.
Dr. Ladapo is an associate professor of medicine at UCLA’s David Geffen School of Medicine. Dr. Risch is a professor of epidemiology at the Yale School of Public Health.