Fact check: Vaccines protect against contracting, spreading COVID-19
The claim: The COVID-19 vaccine doesn't stop you from getting or spreading the virus, so it can't protect others
"Since the (vaccine) doesn't stop you from getting it or spreading it... How ...are you actually protecting others," reads text in a Nov. 13 post from a page called The Lion's Roar.
The post accumulated more than 69,000 shares within four days. Similar claims have racked up tens of thousands of interactions on Facebook and Instagram over the past month, according to CrowdTangle, a social media insights tool.
In clinical trials, all three vaccines authorized in the U.S. were found to be safe and effective at preventing severe COVID-19 cases. Since then, public health officials have acknowledged the shots aren't 100% effective at preventing infection – and research suggests immunity wanes over time.
But that doesn't mean the COVID-19 vaccines are worthless. Experts and public health officials say they do protect people from getting infected and spreading the virus.
"This is false information," Akiko Iwasaki, a professor of immunobiology and molecular, cellular and developmental biology at Yale University, said in an email. "Vaccines provide significant protection from 'getting it' – infection – and 'spreading it' – transmission – even against the delta variant."
USA TODAY reached out to The Lion's Roar for comment.
Vaccines decrease chances of infection, transmission
All three COVID-19 vaccines authorized in the U.S. were designed to prevent severe infection, hospitalization and death. But experts and public health officials say the shots also protect people from contracting and spreading the virus.
"What we know is that individuals who are vaccinated are much less likely to be infected therefore much less likely to spread the virus," Dr. Amesh Adalja, a senior scholar at the Johns Hopkins Center for Health Security, said in an email.
Data from clinical trials indicate the vaccines from Pfizer-BioNTech and Moderna are about 95% effective at preventing symptomatic COVID-19 infections. Johnson & Johnson's shot was found to be about 72% effective at preventing moderate to severe disease. (That number is lower partly because of the higher volume of COVID-19 cases in the general population during the trial period.)
The vaccine rollout has affirmed those findings.
Fully vaccinated people made up about 9% of reported COVID-19 deaths in 13 U.S. jurisdictions between April and July, according to the Centers for Disease Control and Prevention. CDC studies have also shown unvaccinated people are 10 times more likely to be hospitalized with COVID-19.
The agency says on its website that, while breakthrough infections are possible, "most people who get COVID-19 are unvaccinated." Experts told USA TODAY the shots provide considerable protection against infection and transmission.
"Yes, it is true that vaccinated individuals can also be infected by and spread SARS-CoV-2 to others," Shweta Bansal, an associate professor of biology at Georgetown University, said in an email. "However, the evidence is crystal clear that risk of transmission for a vaccinated individual is significantly lower than for an unvaccinated individual."
Bansal pointed to data from the United Kingdom, which shows the COVID-19 vaccines reduce the chances of getting infected by 50%-75%. A preprint study, also conducted in the U.K., found that two doses of the Pfizer vaccine are 80% effective against preventing all infections with the delta coronavirus variant.
Data on how COVID-19 vaccination affects transmission is more complicated, but still promising.
"Within the breakthrough infections with delta, the viral load is similar to those who became infected and were unvaccinated," Iwasaki said. "This may be the source of confusion about the claim that vaccines don’t stop you from spreading the virus."
Research indicates vaccinated individuals who get infected with COVID-19 can transmit the virus at a similar level as unvaccinated people. But data also show they get better faster than the unvaccinated, meaning they may be less likely to spread the virus to others. Several studies awaiting peer review back that up.
And of course, the vaccinated are far less like to contract COVID-19 in the first place, as previously noted.
Public health experts are worried that some people who received the COVID-19 vaccine months ago may see their protection diminish over time. But that's not out of the ordinary for a vaccine, and booster shots have been shown to drastically increase protection against the virus.
"The COVID-19 vaccines incontrovertibly decrease (the) spread of the virus," Adalja said. "Just because they are not 100% does not mean it is nothing."
Our rating: False
Based on our research, we rate FALSE the claim that the COVID-19 vaccine doesn't stop you from getting or spreading the virus, so it can't protect others. While vaccinated individuals can get COVID-19, experts and public health officials say they are less likely to contract the virus than unvaccinated people. That means they're also less likely to spread the virus to others. When vaccinated people do get sick, the chances of severe illness, hospitalization or death are low. Research indicates they also get better faster than their unvaccinated counterparts.
Our fact-check sources:
- Centers for Disease Control and Prevention, accessed Nov. 16, COVID Data Tracker: COVID-19 Vaccinations in the United States
- USA TODAY, Nov. 3, Off to fast start, COVID-19 vaccinations for kids 5-11 will ramp up in the coming days
- USA TODAY, Nov. 16, Booster shots could be available to all adults by weekend; Pfizer seeks OK for promising antiviral pill: COVID Updates
- USA TODAY, April 19, America reaches milestone with COVID-19 vaccine widely available to those who want it, but hesitancy still casts a shadow
- USA TODAY, accessed Nov. 17, US COVID-19 map: Tracking cases and deaths
- USA TODAY, Aug. 24, 'Keep your guard up': CDC studies show waning COVID-19 vaccine efficacy as delta variant sweeps US
- Centers for Disease Control and Prevention, Nov. 9, COVID-19 Vaccines Work
- Akiko Iwasaki, Nov. 16, email exchange with USA TODAY
- CrowdTangle, accessed Nov. 17
- USA TODAY, March 27, Comparing the COVID-19 vaccines
- Yale Medicine, Nov. 3, Comparing the COVID-19 Vaccines: How Are They Different?
- USA TODAY, June 21, Fact check: COVID-19 vaccines provide safer, more consistent immunity than infection
- Food and Drug Administration, accessed Nov. 17, COVID-19 Vaccines
- USA TODAY, Oct. 22, 'A modern miracle': Experts marvel at CDC data showing fully vaccinated make up less than 1% of COVID deaths
- USA TODAY, Sept. 11, Unvaccinated are 11 times more likely to die of COVID-19, CDC studies show: Latest updates
- Shweta Bansal, Nov. 16, Email exchange with USA TODAY
- United Kingdom Office for National Statistics, Oct. 18, Coronavirus (COVID-19) Infection Survey Technical Article: Impact of vaccination on testing positive in the UK: October 2021
- MedRxiv, Aug. 24, Impact of Delta on viral burden and vaccine effectiveness against new SARS-CoV-2 infections in the UK
- MedRxiv, July 31, Virological and serological kinetics of SARS-CoV-2 Delta variant vaccine-breakthrough infections: a multi-center cohort study
- MedRxiv, Aug. 25, Viral dynamics of SARS-CoV-2 variants in vaccinated and unvaccinated individuals
- The Lancet, Oct. 29, Community transmission and viral load kinetics of the SARS-CoV-2 delta (B.1.617.2) variant in vaccinated and unvaccinated individuals in the UK: a prospective, longitudinal, cohort study
- Healthline, accessed Nov. 17, Vaccinated People Can Transmit the Coronavirus, but It’s Still More Likely If You’re Unvaccinated
- Healthline, accessed Nov. 17, Vaccinated People May Be Even Less Likely to Transmit COVID-19 Than Previously Thought
- MedRxiv, Oct. 14, Vaccine effectiveness against SARS-CoV-2 transmission to household contacts during dominance of Delta variant (B.1.617.2), August-September 2021, the Netherlands
- MedRxiv, Oct. 15, The impact of SARS-CoV-2 vaccination on Alpha & Delta variant transmission
- USA TODAY, Nov. 12, Is this the fifth COVID-19 wave? Experts fear we may simply come to call it 'winter'
- USA TODAY, Nov. 3, Fact check: Booster shots are normal, not evidence of failed vaccine, experts say
- USA TODAY, Oct. 21, Study finds 3rd Pfizer shot drastically improves protection; CDC panel votes to expand booster options: COVID-19 updates
- Dr. Amesh Adalja, Nov. 16, Email exchange with USA TODAY
- Centers for Disease Control and Prevention, Sept. 17, Monitoring Incidence of COVID-19 Cases, Hospitalizations, and Deaths, by Vaccination Status — 13 U.S. Jurisdictions, April 4–July 17, 2021
- Centers for Disease Control and Prevention, accessed Nov. 17, COVID Data Tracker: Rates of COVID-19 Cases and Deaths by Vaccination Status
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