RATS ON THE WEST SIDE, BEDBUGS UPTOWN: Why Are Bed Bugs So Hard To Kill? Scientists Uncover Genetic Survival Secrets. “Insecticide use, including the now-banned DDT, nearly eradicated bed bug populations by the 1960s, making infestations a rarity. However, over the past two decades, bed bugs have made a global resurgence, largely due to genetic mutations that have rendered them resistant to modern insecticides.”