Control logic in a memory device determines to initiate a string read operation on a first memory string of a plurality of memory strings in a block of a memory array, the block comprising a plurality of wordlines, wherein the first memory string is designated as a sacrificial string. The control logic further causes a read voltage to be applied to each of the plurality of wordlines concurrently and senses a level of current flowing through the sacrificial string while the read voltage is applied. In addition, the control logic identifies, based on the level of current flowing through the sacrificial string, whether a threshold level of read disturb has occurred on the block.