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Our only agenda is to publish the truth so you can be an informed participant in democracy. We need your help. More Info ### I would like to contribute One Time Monthly Yearly Join Now ![](\\" ![](\\" TikTok posts stated on July 31, 2021 in a Tik Tok post: The contagiousness of the coronavirus delta variant is “valued between 5 and 9½,” and if the value is closer to 10, “within six weeks, the whole country will test positive for delta, regardless of vaccination.” ![\\"true\\"](\\" mostly-false/6a6ef6075c162fdccf5eb960e683dcd1.jpg.\\") ![\\"barely- true\\"](\\" false.jpg\\") * Public Health * Coronavirus * TikTok posts ![\\"Tom](\\" By Tom Kertscher August 30, 2021 # Delta’s ‘R naught’ contagiousness rate doesn’t mean entire US will get COVID-19 #### If Your Time is short * One measure rates delta’s contagiousness in the range of what the video states. * But it is a theoretical measure that doesn’t take into account steps such as vaccination and social distancing that reduce the risk of getting COVID-19. * There is no evidence to suggest that everyone, regardless of vaccination status, could become infected. See the sources for this fact-check A TikTok video with more than 535,000 likes claims that if the contagiousness of the COVID-19 delta variant is on the high end of what \"they\" estimate, avoiding infection will be virtually impossible, regardless of vaccination. \"They have found that the R naught of delta is anywhere between 5 and 9½. The R naught value of an infectious pathogen refers to its contagiousness,\" the user says in the three-minute video, which was posted July 31 and was still viral nearly a month later. \"If the R naught is actually closer to 10, within six weeks the whole country will test positive for delta, regardless of vaccination or not. I mean, at that rate, it’s so contagious, all you have to do is just walk past someone with it. … If you’re in close quarters and you walk past someone that’s exhaling out air and you inhale their air — even you just barely brush by them, if you get in their space and they are delta-positive, you are going to get sick. And at this rate, I think that’s going to happen to you whether you are vaccinated or not.\" The conclusion of the claim is incorrect because it doesn’t take into account measures such as vaccination and social distancing that reduce the chances of contracting COVID-19, said Dr. David Dowdy, an infectious-diseases specialist at Johns Hopkins University. He added: \"The whole country testing positive within six weeks is patently false.\" About delta and R naught According to the federal Centers for Disease Control and Prevention, the delta variant is more than twice as contagious as previous variants of the coronavirus and caused nearly 99% of recent coronavirus cases in the U.S. Unvaccinated people are particularly vulnerable: in Los Angeles County as of July 25, unvaccinated people were five times more likely to be infected and 29 times more likely to be hospitalized. The video alludes to one way health experts think about a virus’ infection rate: the basic reproduction number, or R0 (pronounced \"R naught\"). It indicates the average number of times one infected person will transmit the virus to another person. The higher the R0, theoretically, the faster the virus is spreading. The CDC has estimated that delta’s R0 is in the range stated in the video. But even if the R0 were 10, \"that does not mean that everyone, regardless of vaccination status, will be infected,\" said Dr. Céline Gounder, a clinical assistant professor of medicine and infectious disease at New York University’s Grossman School of Medicine. #### Featured Fact-check ![](\\" Instagram_logo_2016.svg/322c808c00e73c217d17772ddd5a0eb5.jpg\\") ![](\\" Instagram_logo_2016.svg/8b142c91ebe468a84a192e6df2b7b994.jpg\\") Instagram posts stated on September 17, 2024 in an Instagram post CDC warns a third of adults may die from dangerous bacteria in ramen noodles. ![\\"true\\"](\\" false/33efdb6633e5e2fdc2d4e2f63383a1e0.jpg.\\") ![\\"false\\"](\\" false.jpg\\") By Jeff Cercone • September 18, 2024 R0 is a theoretical figure that assumes everyone in a population is without immunity and susceptible to infection. \"It is important to realize that that is the number in a completely unmitigated, ‘natural’ environment — no one vaccinated, no one social distancing, no one wearing masks, and no one immune from prior infection,\" said Dr. Perry Wilson, a Yale School of Medicine associate professor. Wilson said the important indicator for predicting cases in the future is what researchers call the effective reproduction number, or Rt. It is the observed average number of people an infected person infects. Delta’s Rt likely between 1 and 2, he said. \"Due to vaccination, prior infection, and masking and distancing, we have mitigated the ability of delta to spread, so the Rt is quite a bit lower than the R0,\" Wilson said. In some places, because of steps such as vaccination and masking, the Rt, while changing daily, is below 1, said Dowdy, indicating that the spread of the virus has been curbed. The estimated Rt in the U.S. as of Aug. 28 is 1, according to a project led by researchers from the London School of Hygiene & Tropical Medicine. Our ruling A TikTok video claims that the contagiousness of the coronavirus delta variant is \"valued between 5 and 9½,\" and if the value is closer to 10, \"within six weeks, the whole country will test positive for delta, regardless of vaccination.\" One measure rates delta’s contagiousness in the range of what the video states, but it is a theoretical measure that doesn’t take into account steps such as vaccination and social distancing that reduce the risk of getting COVID-19. Accounting for those steps, the reproduction number is far lower. There is no evidence to suggest that everyone, regardless of vaccination status, could become infected. We rate the post Mostly False. #### Read About Our Process The Principles of the Truth-O-Meter ### Our Sources TikTok, post, July 31, 2021 PolitiFact, \"Examining how science determines COVID-19\'s \'herd immunity threshold,’\" Jan. 15, 2021 PolitiFact, \"How contagious is the delta variant? It isn’t easy to quantify,\" July 28, 2021 Centers for Disease Control and Prevention, \"Delta Variant: What We Know About the Science,\" Aug. 26, 2021 Centers for Disease Control and Prevention, \"SARS-CoV-2 Infections and Hospitalizations Among Persons Aged ≥16 Years, by Vaccination Status — Los Angeles County, California, May 1–July 25, 2021,\" Aug. 27, 2021 Centers for Disease Control and Prevention, \"Variant Proportions,\" accessed Aug. 27, 2021 Twitter, Centers for Disease Control and Prevention tweet, Aug. 19, 2021 University of Minnesota Center for Infectious Disease Research and Policy, \"CDC: Unvaccinated 5 times more likely to get COVID-19,\" Aug. 24, 2021 Epiforecasts.io, \"National and Subnational estimates for the United States of America,\" Aug. 28, 2021 Email, Dr. Perry Wilson, Yale School of Medicine associate professor, Aug. 27, 2021 New York Times, \"C.D.C. Internal Report Calls Delta Variant as Contagious as Chickenpox,\" Aug. 1, 2021 Email, Dr. David Dowdy, infectious diseases specialist and associate professor at the Johns Hopkins Bloomberg School of Public Health, Aug. 27, 2021 Email, Dr. Céline Gounder, a clinical assistant professor of medicine and infectious disease at New York University’s Grossman School of Medicine, Aug. 27, 2021 ## Browse the Truth-O-Meter ### More by Tom Kertscher slide 4 to 6 of 15 ![](\\" Instagram_logo_2016.svg/322c808c00e73c217d17772ddd5a0eb5.jpg\\") ![](\\" Instagram_logo_2016.svg/8b142c91ebe468a84a192e6df2b7b994.jpg\\") Instagram posts stated on July 19, 2023 in an Instagram post: A wind turbine must “spin continually for over four years just to replace the energy it took to manufacture it.” ![\\"false\\"](\\" ![\\"false\\"](\\" By Tom Kertscher • July 28, 2023 ![](\\" ![](\\" TikTok posts stated on July 15, 2023 in un video en TikTok: \"Biden elimina ‘tráfico sexual de menores’ como una de las prioridades del Departamento de Justicia de su gobierno”. ![\\"false\\"](\\" ![\\"false\\"](\\" By Maria Briceño • July 25, 2023 ![](\\" Instagram_logo_2016.svg/322c808c00e73c217d17772ddd5a0eb5.jpg\\") ![](\\" Instagram_logo_2016.svg/8b142c91ebe468a84a192e6df2b7b994.jpg\\") Instagram posts stated on July 17, 2023 in an Instagram post: \"Florida to ban mRNA vaccines as credible evidence of biological weapons.\" ![\\"false\\"](\\" ![\\"false\\"](\\" By Tom Kertscher • July 18, 2023 ![](\\" ![](\\" Facebook posts stated on August 26, 2023 in a Facebook post: Video suggests Canada wildfires were deliberately set to advance “smart cities” push. ![\\"false\\"](\\" ![\\"false\\"](\\" By Tom Kertscher • August 30, 2023 ![](\\" Instagram_logo_2016.svg/322c808c00e73c217d17772ddd5a0eb5.jpg\\") ![](\\" Instagram_logo_2016.svg/8b142c91ebe468a84a192e6df2b7b994.jpg\\") Instagram posts stated on August 26, 2023 in a video: Women vaccinated against COVID-19 face \"unknown side effects that could perpetually go down through the lineage\" to their children. ![\\"false\\"](\\" ![\\"false\\"](\\" By Tom Kertscher • August 29, 2023 ![](\\" ![](\\" Facebook posts stated on August 25, 2023 in a Facebook post: As of Aug. 25, \"Luis Rubiales has resigned as the president of the Spanish Football Federation.\" ![\\"false\\"](\\" ![\\"false\\"](\\" By Tom Kertscher • August 29, 2023 ![](\\" Instagram_logo_2016.svg/322c808c00e73c217d17772ddd5a0eb5.jpg\\") ![](\\" Instagram_logo_2016.svg/8b142c91ebe468a84a192e6df2b7b994.jpg\\") Instagram posts stated on August 24, 2023 in an Instagram post: The World Health Organization said there is \"a possible causal relationship\" between COVID-19 vaccines and multiple sclerosis. ![\\"false\\"](\\" ![\\"false\\"](\\" By Tom Kertscher • August 28, 2023 ![](\\" ![](\\" Facebook posts stated on August 9, 2023 in a Facebook post: Video shows military planes over Nashville \"dispersing materials into the atmosphere\" for geoengineering. ![\\"false\\"](\\" ![\\"false\\"](\\" By Tom Kertscher • August 23, 2023 ![](\\" ![](\\" Facebook posts stated on August 20, 2023 in a Facebook post: “Official statement — Putin assassinated in the Kremlin!” ![\\"pants-fire\\"](\\" th.jpg\\") ![\\"pants-fire\\"](\\" pants-fire.jpg\\") By Tom Kertscher • August 22, 2023 ![](\\" ![](\\" Facebook posts stated on August 8, 2023 in a Facebook post: \"The federal government has just declared a major food shortage emergency\" in six states. ![\\"false\\"](\\" ![\\"false\\"](\\" By Tom Kertscher • August 16, 2023 ![](\\" ![](\\" Steve Kirsch stated on August 8, 2023 in a blog post: COVID-19 vaccines have killed 676,000 Americans. ![\\"pants-fire\\"](\\" th.jpg\\") ![\\"pants-fire\\"](\\" pants-fire.jpg\\") By Tom Kertscher • August 14, 2023 ![](\\" Instagram_logo_2016.svg/322c808c00e73c217d17772ddd5a0eb5.jpg\\") ![](\\" Instagram_logo_2016.svg/8b142c91ebe468a84a192e6df2b7b994.jpg\\") Instagram posts stated on August 6, 2023 in a viral image: California passed a law “reducing penalties for oral, anal sex with willing children.” ![\\"false\\"](\\" ![\\"false\\"](\\" By Tom Kertscher • August 9, 2023 ![](\\" ![](\\" TikTok posts stated on June 22, 2023 in a post: A new law allows people to permanently erase unpaid debt older than two years from their credit records. ![\\"false\\"](\\" ![\\"false\\"](\\" By Tom Kertscher • August 1, 2023 ![](\\" Instagram_logo_2016.svg/322c808c00e73c217d17772ddd5a0eb5.jpg\\") ![](\\" Instagram_logo_2016.svg/8b142c91ebe468a84a192e6df2b7b994.jpg\\") Instagram posts stated on July 28, 2023 in a video: “Skin cancer is a relatively new phenomenon in the last 60 years or so.” ![\\"false\\"](\\" ![\\"false\\"](\\" By Tom Kertscher • August 1, 2023 ![](\\" ![](\\" Facebook posts stated on July 26, 2023 in a Facebook post: Says Bill Gates said, “We’re taking things that are genetically modified organisms, and we’re injecting them into little kids’ arms” in the context of the COVID-19 pandemic. ![\\"false\\"](\\" ![\\"false\\"](\\" By Tom Kertscher • July 31, 2023 ![](\\" Instagram_logo_2016.svg/322c808c00e73c217d17772ddd5a0eb5.jpg\\") ![](\\" Instagram_logo_2016.svg/8b142c91ebe468a84a192e6df2b7b994.jpg\\") Instagram posts stated on July 19, 2023 in an Instagram post: A wind turbine must “spin continually for over four years just to replace the energy it took to manufacture it.” ![\\"false\\"](\\" ![\\"false\\"](\\" By Tom Kertscher • July 28, 2023 ![](\\" ![](\\" TikTok posts stated on July 15, 2023 in un video en TikTok: \"Biden elimina ‘tráfico sexual de menores’ como una de las prioridades del Departamento de Justicia de su gobierno”. ![\\"false\\"](\\" ![\\"false\\"](\\" By Maria Briceño • July 25, 2023 ![](\\" Instagram_logo_2016.svg/322c808c00e73c217d17772ddd5a0eb5.jpg\\") ![](\\" Instagram_logo_2016.svg/8b142c91ebe468a84a192e6df2b7b994.jpg\\") Instagram posts stated on July 17, 2023 in an Instagram post: \"Florida to ban mRNA vaccines as credible evidence of biological weapons.\" ![\\"false\\"](\\" ![\\"false\\"](\\" By Tom Kertscher • July 18, 2023 ![](\\" ![](\\" Facebook posts stated on August 26, 2023 in a Facebook post: Video suggests Canada wildfires were deliberately set to advance “smart cities” push. ![\\"false\\"](\\" ![\\"false\\"](\\" By Tom Kertscher • August 30, 2023 ![](\\" Instagram_logo_2016.svg/322c808c00e73c217d17772ddd5a0eb5.jpg\\") ![](\\" Instagram_logo_2016.svg/8b142c91ebe468a84a192e6df2b7b994.jpg\\") Instagram posts stated on August 26, 2023 in a video: Women vaccinated against COVID-19 face \"unknown side effects that could perpetually go down through the lineage\" to their children. ![\\"false\\"](\\" ![\\"false\\"](\\" By Tom Kertscher • August 29, 2023 ![](\\" ![](\\" Facebook posts stated on August 25, 2023 in a Facebook post: As of Aug. 25, \"Luis Rubiales has resigned as the president of the Spanish Football Federation.\" ![\\"false\\"](\\" ![\\"false\\"](\\" By Tom Kertscher • August 29, 2023 ### Delta’s ‘R naught’ contagiousness rate doesn’t mean entire US will get COVID-19 * ![](\\" ![](\\" House Majority PAC stated on September 9, 2024 in a television ad: Laurie Buckhout is “trying to get to Congress to pass a national abortion ban, allowing politicians to ban abortions with no exceptions and prosecute women if they get an abortion, treating women right here like criminals.” ![\\"barely-true\\"](\\" th.jpg\\") ![\\"barely-true\\"](\\" barely-true.jpg\\") By Paul Specht • October 1, 2024 * ![](\\" ![](\\" Donald Trump Jr. stated on September 9, 2024 in a post: “Less than three months ago, Kamala Harris and her administration blocked 300,000 unvetted Haitian migrants from being deported out of our country.\" ![\\"barely-true\\"](\\" th.jpg\\") ![\\"barely-true\\"](\\" barely-true.jpg\\") By Kwasi Gyamfi Asiedu • September 30, 2024 * ![](\\" ![](\\" X posts stated on September 30, 2024 in an X post: Photo shows President Joe Biden lounging on the beach \"while towns all over America were being wiped out” by 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The contagiousness of the coronavirus delta variant is valued between 5 and 9½ and if the value is closer to 10 within six weeks the whole country will test positive for delta regardless of vaccination