The term "breakthrough" infection is so off the mark
—Most only show up because a routine PCR test was done
—Rarely are there symptoms.
—The viral load is so low sequencing is not possible in most
—The chance that someone could spread covid is close to zero, yet to be documented pic.twitter.com/YhwHSHlD3q

— Eric Topol (@EricTopol) May 14, 2021

Exactly. Vaccines are working as expected. Panic not warranted.