I’m not sure whether people who don’t normally work with numbers on a daily basis truly appreciate the difference between a virus where each carrier infects on average 2 other people compared to a virus that infects on average 5 others, but here’s how it plays out over a few weeks if you do the math.
Epidemiologists have now determined that COVID delta is more contagious than were childhood viruses like chickenpox in the 1950s. I was a young child in the days before chickenpox vaccines, and when the virus arrived locally it tore through communities like wildfire. If you didn’t get it in kindergarten you got it in grade 1 or maybe grade 2.
Nobody made it to grade five without getting chickenpox and its three sisters: mumps, measles and German measles. It was a rite of passage and the four of them were known, with good reason, as universal childhood diseases. (Adults were immune as a result of their own childhood encounters with these self-immunizing diseases.)
Epidemiologists are now starting to point out that delta COVID has the “transmission power” to spread like the universal childhood diseases in the 1950’s – the bug is aggressive enough that it will spread to every niche of the community, finding and infecting virtually everyone who is not vaccinated (and some that are). If that sounds far-fetched – just look at the numbers in the table above.
For additional reference: from recent infamous CDC power point