How best to stay safe during the pandemic has changed in the last few weeks as community levels of COVID-19 infections with the delta variant have surged. The delta variant was first detected in India in December 2020 and arrived in the U.S. in about March 2021. The dramatic spread of the delta variant is due to its ability to replicate (build up in the system) much more rapidly than prior variants, including the U.K. variant now called alpha. Instead of needing six days to build up, it takes half that time for an infected person to pass on the virus. There is a thousand times the load of virus in the nose and upper air passages! Most likely, multiple mutations have resulted in the more infectious and dangerous delta variant. Research is ongoing to understand this process better. 

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