Whenever there is a decline of righteousness, O Arjuna, and rise of unrighteousness, then I manifest Myself! (Bhagavad-Gita 4.7). When people have bad health they can just go to Ayurveda and receive the grace of good health. This medicine for life comes from the highest god so it is a real blessing from the divine in the time of decline of righteousness. Dhanvantri is the god of Ayurveda.