Longtime Pokemon fans may be aware of Pokerus, a  “Pokemon Virus” that could rarely infect the player’s Pokemon, granting them boosted Effort Values in battle without any ill effects.

After having appeared in every game since Pokemon Gold/Silver, it seems that Pokerus has been removed from Pokemon Scarlet And Violet. This information comes from Pokemon dataminer Mattyoukhana, who conducted a number of tests showing that not only does it not exist on Wild Pokemon, Pokemon forcibly given Pokerus through hacking will not possess its unique effect, nor will it spread to other Pokemon like it used to in past games.

As an addendum, auto battles via the Let's Go feature do not reward ANY EVs, only lessened Exp. Point gains.

Your most optimal ways of EV training will probably be normally KOing/capturing a ton of Pokémon via Mass Outbreaks, or feeding them a lot of vitamins.

— Matt (@mattyoukhana_) November 18, 2022

Fans have put forth a number of theories as to why this feature could have been removed. On the more practical side, its possible that Pokerus simply was not needed anymore due to the greater ease of Effort Value training in recent titles. On the more speculative side, some believe that it was removed to avoid comparisons to the COVID-19 pandemic.

Without any official acknowledgement from Game Freak however, it is likely we will not know the definitive answer to this mystery.

What do you think? Let us know in the comments.