[driftdiver]

There have been other studies which found the majority of shopping carts had ecoli, fecal matter, and other nasties on them.

[jimbo123]

The majority of EVERYTHING in NYC had ecoli, fecal matter, and other nasties on it.

[wideawake]

Shopping carts are no different from pretty much any other public object: park benches, bus seats, monkeybars, swings, etc.

Nothing particularly special or more dangerous about them than anything else.