I'm not entirely sure, but perhaps Nurse Joy only tells you that your Pokemon have Pokerus the first time she sees the infected Pokemon, so she won't tell you again when you bring the same infected Pokemon back.
that's correct, she only tells you the 1st time.
BTW, is it possible to get pkrs on FRLG? I mean actually get it from a wild pokemon, not from trading. (Pkrs can't be lost or spread on FRLG, so that's why I'm asking). If not, then it's possible Nurse Joy won't say anything about pkrs at all.
How do you get PokeRus?
There's a slim chance (less than a shiny) of the wild pokemon you find having pkrs, and you have to battle/catch it.
_________________Need homework help? "Screw the Ivys, I'm applying to Smogon University!"ShiniesRuby:
Spinda, Golbat, DuskullPearl:
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