Washing produce, even very carefully, may not remove all the bacteria present.
Rough surfaces provide lots of places in which bacteria can hide out. You may want to wash rougher-surfaced fruit more carefully.
However, according to Live Science:
“For vegetables and other foods that are eaten raw, the best way to prevent outbreaks … is through cleaner farming practices … When the water used to irrigate the food crops is drawn from wells that are near livestock, fecal bacteria can spread through the water to the food.”
Source: Live Science May 12, 2010