A drive? Every child born in the US is recommended to take 15+ doses of various vaccines. Most of them are required to enter public school. Multiple new vaccines (like HPV and shingles) have been launched with millions of doses delivered in the same time period.

As you are probably aware: people tend to die somewhere between 50 and 100 with high regularity, leading to more entries in VAERS if large numbers of people in that age range are vaccinated.

It's children that have not been vaccinated in large numbers this time around.