My brother has bumps on his body?

He has these bumps on:

Chest

Upper back

Abdominal area.

The bumps are very tiny... they are slightly red and itch. He does have allergies but he hasn't been in any plants he is allergic too. He doesn't shower every day but more like every other day. Could this affect something. He has them on his limbs (not as much as his torso). They feel like bug bites almost.. but they aren't. We have gotten rid of the bug problem in our trailer so I can't imagine that being a factor,