Worm in food

on the 26/10/2015 I purchased a chicken burger meal at McDonalds which was a take away for my daughter as she was eating she found 1 live worm in the burger after taking to bites of it , I than took it back which the manager advised me if my daughter ate it ,it's more protein for her he was rude en arrogant , what kind of service is this as my daughter cud of got sick en all they cud do was give me another burger an stating that they will contact me till date I await feedback from them with the worm issue