Towards the end of the Dominion War, the founders and the Great Link become

>! infected with a disease, that we later learn was planted by Section 31 through Odo, and infected to the rest via linking. Odo [linked with the Female Changeling][1] at the beginning of Season 6,

and from that point the wormhole was impassable to the Dominion (due to the mines and then the wormhole prophets), so how did

>! he or she pass the disease to the Great Link

?


  [1]: http://memory-alpha.wikia.com/wiki/Behind_the_Lines_(episode)