Yes, illness is related to chakra.
We have two layer auras, if chinese medical is included would be 3 layers. There are chakras in the aura.
Aura contains our:
They all have connections, if one goes wrong, others will be affected.
For example, if our health go bad, our luck would decrease. We can energize the Chakra to increase the health and then luck may increase.
Karma is like a barrier, if karma is weak, then the person can easily get sick. So that is why doing good deeds will increase one's health and luck.
Chakra is the energy point.
Luck is the aura and had connection with Karma.
Health is connected to the Chakra.
Karma is also the aura. (Barrier)
That's why in Buddhism, they would suggest people to do more good deeds to increase one's Karma, then they would have good health, wealth, and good fortune.
Bad Karma attracts illness, so if the person got healed, but the karma will still make the person sick.
Good Karma attracts positive energy to the person, if the person got sick, he or she will easily recovered.
So that is why I suggest Karma, instead of Chakra. Chakra healing only prevent illness for a time. But Karma is for a longer time.
It depends on the person.