Here's what you need to know:
* Pokerus is a rare, contagious condition. It's like a flu that affects Pokémon, but instead of making them sick, it helps them grow stronger.
* It speeds up EV (Effort Value) gain. EV's determine a Pokémon's stats, so Pokerus essentially allows them to train faster.
* It doesn't affect a Pokémon's health or status. You can safely battle with a Pokerus-infected Pokémon without any negative consequences.
* It can be spread to other Pokémon. This is why it's considered beneficial – you can deliberately spread it to your team to help them train faster.
While Pokerus can be helpful, it's not a cheat code. You still need to train your Pokémon and use effective strategies in battles. However, Pokerus can definitely make the training process a lot faster and more efficient.