Thanks-—and those that previously had Covid?
There isn’t a ton of data to go on just yet with Delta, but the data so far does appear to show an increase in the rate of reinfection (i.e. if you had COVID-19 before, you’re more likely to get reinfected with Delta than you were with previous variants), but that rate is relative and still pretty low. Previous variants showed a fairly consistent rate of about 1 in 10,000 people facing reinfection. Not bad at all. Places like the UK, Kentucky, and others have reported increases in reinfection rates with Delta, but rarely try to quantify it yet because that data is difficult to come by (particularly since many wouldn’t even know they had it before if they were asymptomatic).
Best estimates I can find is that risk of reinfection with Delta is 1 in 6,500 to 1 in 7,000 or about ~0.15%. Beyond that, reinfection has almost always presented as a less severe case than the initial infection, so the vast majority of those reinfected would have a significantly reduced risk of severe illness or death.
Long story short, if you’ve had COVID-19 before, it’s possible - but unlikely - you would get infected with Delta, and if you do, it’s unlikely that infection would lead to any serious problems.