The Pokérus (Japanese: ポケルス Pokérus), from "Pokémon virus", is a microscopic life-form that may attach to Pokémon, first appearing in 🍉 the Generation II games. It is a beneficial mechanic that a Pokémon can obtain.

In the games

When a Pokémon has the 🍉 Pokérus, it gains double the effort values from battling (e.g., fighting a Magikarp will give two Speed EVs, rather than 🍉 one). Effort points gained from Vitamins and Feathers are not doubled. The infected Pokémon can infect other Pokémon with the 🍉 virus for a period of one to four days. However, the Pokérus timer can be delayed by several methods, such 🍉 as by placing the infected Pokémon in a PC Box.

While it is represented similarly to status conditions, the Pokérus is 🍉 not a status condition, so it cannot be healed at a Pokémon Center or with any status condition healing item.

Pokérus 🍉 has a 3 in 65,536 (or approximately a 1 in 21,845) chance of being generated on one of the player's 🍉 Pokémon after a battle, making it rarer than encountering or hatching a Shiny Pokémon. If any of the player's Pokémon 🍉 are infected, the Pokérus may spread among Pokémon in the player's party after any battle.