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https://www.theguardian.com/world/2021/jul/30/covid-delta-variant-guidelines-masks-cdc-paper-transmission
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Citing data from an outbreak in a county in Massachusetts, the CDC document suggested that infections in vaccinated people can produce viral loads similar to those who are unvaccinated and infected with the variant.
However, scientists acknowledge that the likelihood of vaccinated people spreading the virus, if infected, is much rarer compared with unvaccinated people.
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