while the comment above is a complete lunacy, it's very easy to point out that:

* Chips need a power source. If it was easy to find one inside the human body, we wouldn't have so much hassle replacing batteries in heart pacemakers and other implants.

* Sending/receiving radio waves requires antennae of certain physical sizes. Something that can go through a needle wouldn't really make it.

Making these arguments is harder than pressing the "flag" button, but that's the only way of actually reducing the division in our society rather than furthering it.