say you’ve already had it long ago and now your children has chicken pox. how likely will someone else get it from interacting with you (not your children)? does the answer to this question apply to other diseases that spread the same way?
Purely an anecdote:
When my younger daughters were 1 & 3, they had chicken pox. A contractor who was building a deck for us walked from the front door directly to the back door, and out onto the old deck. He may have touched the handle of the sliding door onto the deck. He was in the house for less than 30 seconds, and had all other conversations with us outside. He still caught it.
ETA: He had never had chicken pox before. My wife and I both had it as youngsters, and did not catch it from our kids when they had it.
Chicken Pox (Varicella Zoster) is transmitted by direct contact with the sores of an infected patient or by droplets (ie coughing) from an infected patient. Theoretically, if you touched your child’s sores and didn’t wash your hands you could transmit it to another individual.