Since measles is so contagious, even with herd immunity, it can find a weak link and spread.
"Well, then there is one weak link we have got to strengthen right away," said the lad cheerfully.
Hit the source, the weak link, the roots of the poison tree.
Here, then, was the weak link in Ruiz Gregorio's chain twisted to the breaking point at the very outset.
But the adventurer did dare, and the loophole, the weak link, was exposed.
Every man taught how a weak link may break a chain and realizing himself as a link and only a link!
There must be not one weak link in his close-meshed chain of propositions.
She had been the weak link in his life, the life which he had so wanted to crown with success.
Nagel was the weak link in their armor—a threat to their safety.
With his characteristic thoroughness Cook left no weak link in the claim which he made on behalf of his nation.