wasnt cable cured of the t.o. virus when he lost his powers?
Nah. He cured himself when he raised to Messiah levels. After Surfer pwned him, TO was reintroduced to his body in order to stabilise his powers (and supress them as well).
Later, after he was de-aged, it was outright staten, then soon TO will be rejected by his organism again. When he burnt his powers curing Deadpool, all the remains went into supressing TO, lke back in his classic days.