Before the school year began, the Delta variant resulted in more cases than had been seen at the end of the 2020-21 school year. This called for greater urgency in making sure that all children ages 12 to 19 were vaccinated, along with their parents and teachers. We also began to see the rise of breakthrough infections and, in some states, they total 30-40% of all infections, although it is important to remember that such infections are far less likely to lead to severe infections or hospitalizations.
What Vaccinated People Need to Know About Breakthrough Infections – The New York Times.pdf
Covid’s Delta Variant- What We Know – The New York Times.pdf