Widely reported claims misrepresent effectiveness of COVID-19 vaccines

By Saranac Hale Spencer

SciCheck Compendium

As the virus that causes COVID-19 has evolved, vaccines have become less effective at preventing symptomatic infections, but remain highly effective at preventing severe illness and death. This change has been misrepresented by influential anti-vaccine activists who falsely claim that it means that vaccines don't work and have been ineffective from the start.

How effective are vaccines?

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Viruses mutate, or change, as they multiply. That's a big part of why currently available vaccine formulations don't work as well at preventing infection with the virus that causes COVID-19.

Those vaccines, made by Moderna, Pfizer/BioNTech, and Johnson & Johnson, were highly effective at preventing both symptomatic infections and severe illness with early strains of the virus. But they are less effective against infection with the currently circulating omicron subvariants.

Public health officials have recognized this shift and changed their recommendations accordingly, in an effort to tackle a disease that became the third leading cause of death in the United States in 2020 and 2021 and has killed more than a million people across the country.

But anti-vaccine activists and those casting doubt on the seriousness of COVID-19 have twisted those recommendations to suggest that health establishments have been misleading the value of vaccines from the start.

For example, influential conservative David Harris Jr., who has 1.5 million followers on Instagram, posted a pair of videos featuring Brett Sutton, the health director for the state of Victoria, Australia. One of the videos is from April and shows Sutton encouraging people to get a booster dose, saying he can help prevent people from "getting infected in the first place." The other video shows part of a press conference in August, when Victoria was suffering from a spike in cases, where Sutton said: “Despite two, three, four doses of the vaccine, it is not that good at preventing infection in first place".

Harris did not include the dates of the videos, only labeling them "Before" and "Now." In the caption, he referred to his earlier claim that the COVID-19 vaccine "doesn't work" and wrote, "Wonder which of my other conspiracy theories will be proven true now???"

We have seen similar claims on social media and beyond. They have been posted on platforms such as the right-wing website Gateway Pundit, which claimed in a headline that the Centers for Disease Control and Prevention (CDC) “Finally Admits Their Vaccines Don't Prevent Someone From Getting or spread the virus.”

And they appeared on a San Diego television station that has a history of promoting dubious claims about COVID-19. The station featured a guest panelist who claimed that the CDC had said about the vaccines, that "it turns out they don't really work anyway" and that CDC officials "knew they weren't going to do what they said they were going to do." .

That guest was Dr. Kelly Victory, who maintains an active medical license in Colorado and Ohio, but according to her LinkedIn profile, has been a disaster preparedness training consultant for the last 16 years. She also campaigned against the Affordable Care Act in 2012.

Victory has railed against most public health recommendations over the course of the pandemic, stating that "masks don't work" and symptom-free spread "just doesn't happen with respiratory viruses." In an appearance on a radio show in 2021, Victory said that she had been "censored" for making those claims. But her claims are simply not true.

Other similar claims continue to appear on the internet, such as the meme shared by Donald Trump Jr., suggesting that the recent update to the CDC's recommendations is consistent with what has been said all along by those who have downplayed the severity of the disease and questioned the value of vaccines.

But the new guidance does not indicate that health care experts were wrong about vaccinations or any other mitigation measures they have recommended.

Very effective against the initial outbreak

“The truth is that the efficacy of vaccines has changed with each new variant,” Dr. Peter Hotez, co-director of the Center for Vaccine Development at Texas Children's Hospital and dean of the Texas Children's Hospital, told us in a telephone interview. National Tropical Medicine at Baylor College of Medicine.

When the vaccines were licensed for emergency use in 2020, they were licensed on the basis of their demonstrated ability to prevent symptomatic disease, he said. And large clinical trials showed that the efficacy was high.

For example, updated trial results reported to the US Food and Drug Administration (FDA) for full authorization showed that Moderna's vaccine was 93.2% effective in prevention of symptomatic disease for at least two weeks after the second dose, in persons over 18 years of age.

The vaccines also had very high effectiveness when they were first presented to the public in the real world, that is, outside of trials.

“The initial SARS-CoV-2 that we had, that initial wild type, the vaccine against it, did work against the infection,” Dr. Rochelle Walensky, director of the CDC, said in a recent interview on Fox News. “It worked really well against infection. It also worked against serious illness and death.”

A promising early study from Israel showed that the vaccines had been more than 90% effective in preventing both disease with symptoms and infections without symptoms in the first days of the vaccination campaign.

“That was really exciting because it meant that maybe we could get vaccinated until this pandemic is over,” Hotez said.

After the first variant, alpha, emerged, vaccines remained highly effective against infection, severe illness and death, Walensky said.

In May 2021, the CDC said that those fully vaccinated could stop wearing masks.

The virus then mutated, and the delta variant became dominant in the summer of 2021.

The recommendations evolved with the variants

Although vaccines remained effective against severe illness and death from COVID-19, they became somewhat less effective at preventing delta infection.

That's when the CDC reversed its recommendation and said that vaccinated people should wear masks indoors.

That fall, the Biden administration made booster doses available.

The virus continues to change and the omicron subvariants are the ones that dominate today. It is becoming increasingly clear that vaccines are less effective at preventing infections than earlier variants.

This is due to two things, Hotez said: changes in the virus itself and the natural decline in potency of the vaccination over time, which happens with most vaccines.

The CDC noted the waning effect of vaccine immunity in a report in August explaining the most recent changes to its recommendations on COVID-19 prevention, which included a recommendation for a booster dose.

“Overall, booster dosing in the United States remains low, which is concerning given the significant reduction in risk of severe illness and death that boosting provides and the importance of booster doses in counteracting attrition of the immune system. vaccine-induced immunity,” says the paper, which was published in the CDC's Morbidity and Mortality Weekly Report on August 11.

He also noted that vaccines are "highly protective" against severe illness and death, and offer "minimal protection against infection and spread." It's this last part that Victory and others emphasized, not mentioning how effective vaccines are against severe disease.

Victory claimed that the CDC has "recognized" that the vaccines are "essentially ineffective."

But that's not true.

As we've said, the CDC explained that being up-to-date on your immunization schedule provides minimal protection against infection but, more importantly, significant protection against severe disease. Staying current on vaccination means you've received the primary series of doses and any available boosters for your age group, the CDC explained.

“Being up-to-date with vaccination provides a transitory period of increased protection against infection and spread after the most recent dose, although protection may decrease over time,” the CDC said. Hospitalization and death rates are "substantially higher" among unvaccinated adults, especially those over age 65, compared to people who are up-to-date on their vaccinations, the CDC added.

In fact, data from the Hospitalization Surveillance Network Associated with COVID-19 from March 20 to May 31, 2022, show that “hospitalization rates among unvaccinated adults were 3.4 times higher than those of vaccinated adults,” according to an August 26 CDC report.

Translated by Catalina Jaramillo.

Editor's Note: The SciCheck Vaccination/COVID-19 Project is made possible by a grant from the Robert Wood Johnson Foundation. The foundation has no control about editorial decisions FactCheck.org, and the views expressed in our articles do not necessarily reflect the views of the foundation. The goal of the project is to increase access to accurate information about COVID-19 and vaccines, and reduce the impact of misinformation.