Summary By Dr. Jessica Steier & Dr. Andrea Love
Unbiased Science Podcast 29 August 2021
Last month, data from a CDC internal presentation was leaked and taken out of context. The agency thinks that communication on vaccine effectiveness and breakthrough infections could be improved. The document contained several slides that were considered confidential (meaning that they included preliminary data that are subject to change).
It is crucial to analyze all slides before sharing them and spreading the wrong information. Let’s dive into the presentation:
Breakthrough cases are expected and will be seen more often as more people get vaccinated. However, they are still rare and don't indicate that the vaccines are not working. There is an 8-fold reduction in disease incidence, a 25-fold reduction in hospitalization, and a 25-fold reduction in death in the vaccinated population vs unvaccinated. Preliminary studies suggest that the number of hospitalizations is increasing within the vaccinated group (still less than the unvaccinated), mainly among the elderly who are at higher risk of infection.
The delta variant appears to cause more severe illness when compared to earlier variants. Delta leads to a much higher viral load and is more transmissible than the ancestor strain and almost as transmissible as chickenpox. Based on CDC data, it appears that breakthrough cases MAY be as transmissible as unvaccinated cases.
The document also contains information about vaccine effectiveness (VE); preliminary VE data from May and June 2021 were disclosed in the presentation. 88%-87% reduction against hospitalization and 90% against symptomatic infections were reported. Despite presenting a good VE in the general population, it was lower among immunocompromised communities and nursing home residents.
The CDC’s goal was to improve the communication on vaccine effectiveness, breakthrough cases, and the delta variant. After analyzing published and preliminary data -- given higher transmissibility, vaccine coverage, and VE -- it was concluded that universal masking is essential.
The war has changed. But we know how to fight.
With everyone's help, we can reduce the Delta transmission.
Want more Unbiased Science? Check out our Patreon!
Dang - It won't let me post the link to the report.
Google : Improving communications around vaccine breakthrough and vaccine effectivness
People are misreading documents. Key point is " Breakthrough cases are POTENTIALLY as transmissible as unvaccinated, but for shorter period of time". The high viral load that some have referred to in previous posts is only refering to breakthrough infections post vaccination (something like 1% from memory). That means that post vaccination, you can still get Covid, most (like 99% of non imunocompromised people) will show no symptoms what so ever. This cohort have little to no chance of spreading it to others.
https://www.bmj.com/content/374/bmj.n2074