'The war has changed': Internal CDC document urges new messaging, warns Delta infections likely more severe

• The internal presentation shows that the agency thinks it is struggling to communicate on vaccine efficacy amid increased breakthrough infections
• The delta variant of the coronavirus appears to cause more severe illness than earlier variants and spreads as easily as chickenpox, according to an internal federal health document that argues officials must 'acknowledge the war has changed.'
• The document is an internal Centers for Disease Control and Prevention slide presentation, shared within the CDC and obtained by The Washington Post. It captures the struggle of the nation's top public health agency to persuade the public to embrace vaccination and prevention measures, including mask-wearing, as cases surge across the United States and new research suggests vaccinated people can spread the virus.
• The document strikes an urgent note, revealing the agency knows it must revamp its public messaging to emphasize vaccination as the best defence against a variant so contagious that it acts almost like a novel virus, leaping from target to target more swiftly than Ebola or the common cold.
• It cites a combination of recently obtained, still unpublished data from outbreak investigations and outside studies showing that vaccinated individuals infected with delta may be able to transmit the virus as easily as those who are unvaccinated. Vaccinated people infected with delta have measurable viral loads similar to those who are unvaccinated and infected with the variant.
• 'I finished reading it significantly more concerned than when I began,' Robert Wacher, chairman of the Department of Medicine at the University of California at San Francisco, wrote in an email.
• CDC scientists were so alarmed by the new research that the agency earlier this week significantly changed guidance for vaccinated people even before making the new data public.
• The data and studies cited in the document played a key role in revamped recommendations that call for everyone - vaccinated or not - to wear masks indoors in public settings in certain circumstances, a federal health official said. That official told The Post that the data will be published in full on Friday. CDC Director Rochelle Walensky privately briefed members of Congress on Thursday, drawing on much of the material in the document.
• One of the slides states that there is a higher risk among older age groups for hospitalization and death relative to younger people, regardless of vaccination status. Another estimates that there are 35,000 symptomatic infections per week among 162 million vaccinated Americans.
• The document outlines 'communication challenges' fuelled by cases in vaccinated people, including concerns from local health departments about whether coronavirus vaccines remain effective and a 'public convinced vaccines no longer work. Booster doses needed.'
• The presentation highlights the daunting task the CDC faces. It must continue to emphasize the proven efficacy of the vaccines at preventing severe illness and death, while acknowledging milder breakthrough infections may not be so are after all, and that vaccinated individuals are transmitting th virus. The agency must move the goal posts of success in full public view.
• The CDC declined to comment.
• 'Although it's rare, we believe that at an individual level, vaccinated people may spread the virus, which is why we updated our recommendation,' according to the federal health official, who spoke on the condition of anonymity because they were not authorized to speak publicly. 'Waiting even days to publish the data could result in needless suffering and as public health professionals we cannot accept that.'
• The presentation came two days after Walensky announced the reversal in guidance on masking among people who are vaccinated. On May 13, people were told they no longer needed to wear masks indoors or outdoors if they had been vaccinated. Even people who are vaccinated should wear masks indoors in communities with substantial viral spread or when in the presence of people who are particularly vulerable to infection and illness, the CDC said.