C.D.C. Internal Report Calls Delta Variant as Contagious as Chickenpox Infections in vaccinated Americans also may be as transmissible as those in unvaccinated people, the document says, and lead more often to severe illness. New mask guidelines trigger backlashThe Centers for Disease Control and Prevention’s (CDC) new mask guidance is spurring confusion and backlash as the country tries to respond to the shifting threat of the delta variant. U.S. CDC internal report says Delta variant as contagious as chickenpox - reportThe U.S. Centers for Disease Control and Prevention (CDC) has described the Delta variant of the coronavirus as being as transmissible as chickenpox and cautioned it could cause severe disease, the Washington Post said, citing an internal CDC document. CDC internal memo calls delta variant as contagious as chickenpox: reportAn internal memo from the Centers for Disease Control and Prevention (CDC) reportedly says that the highly transmissible delta variant may cause worse illnesses than other versions of COVID-19 and is more contagious than other leading viruses.&nbs Delta variant spreads as quickly as chickenpox even among vaccinated, leaked CDC data concludesEach person infected with the Delta variant can end up spreading the virus to eight or nine others 'The war has changed': CDC document warns delta variant more severe than previously thoughtThe data in the CDC slideshow reportedly prompted the CDC’s new mask guidance. Coronavirus Delta variant as transmissible as chickenpox: CDCInternal CDC report, quoted by NYT, says Delta variant likely to break through protections afforded by the vaccines. CDC team: 'War has changed' as delta variant dangers emergeNew evidence showing the delta variant is as contagious as chickenpox and may be more dangerous than other versions has prompted U.S. health officials to consider changing advice on how the nation fights the coronavirus, internal documents show.