u. s department of public health and human services and currently a clinical associate professor at stanford, and we always appreciate you coming on the show doctor when the cdc reverse course on masking a lot of experts then asked, where's the data? now we have the data. what does it say about the dangers posed by the delta variant? yeah. good afternoon. great to be here. so you know this is emerging data again. we always want more data because this is big and the more people we have, the more we studied, the better we understand, and we're not relying on outliers, but so far what we know is that the delta variant is highly transmissible much more transmissible than the alpha variant, which is the covid strain. that we had based all of our return back to normal guidance on which really happened in may, where the lockdowns and in essence, the, um, uh, removal from masks occurred. so what we're seeing is that the delta variant is very transmissible. we already knew that from abroad, but we're seeing it in the united states, and we're also seeing that people who are vaccinated can in fact. car