The Pokérus Host
The user who is affected by Pokérus, also called the host, can be recognised by the Pokérus Icon next to their name on the User Page. The Pokérus link on the top of every page can be used to find the current host. Whoever is the current Pokérus host will see the icon at the top of the page next to Today's Interactions.
The user affected by Pokérus changes every 15 minutes, starting at server reset.
To obtain Pokérus it is necessary to interact with the current Pokérus host. When selecting the next Pokérus host it is taken into consideration how many interactions were made with the host; from this, the chance of receiving Pokérus is calculated. Interacting more often with the user raises the chance of getting it, but it is not guaranteed as other users also interact with the host. The selection of the next Pokérus host is completely up to chance, so it is still possible for a user who only interacted once with the past host to become the next Pokérus host. The interactions that were made before the host got Pokérus are also taken into consideration, though it is necessary for the new host to be active within the last 15 minutes for the interactions to count.
If for any reason nobody interacted with the host, then a random Staff member will receive it.
After the Pokérus has ended, one is immune to it for one hour. This is a measurement to prevent one user getting Pokérus repeatedly. This immunity does not affect the user after it has ended and does not change the chances of getting Pokérus again.
Effects of Pokérus
Only the user who has Pokérus gets affected by it. Interacting with a Pokérus host doubles the amount of EXP which the user would usually get, which also stacks with Niet's Bonus Counter, the Hypermode EXP bonus, and bonuses from Wishforge Badges. On the other hand, if a Pokérus host interacts with Pokémon or Eggs then the received Interaction Points are doubled, which also stacks with Garthic's Counter.
So on a Bonus Day where Interactions are counted ×3, the Pokérus Host would receive the doubled amount, so ×6 Interactions. In that case an Egg would get 300 EXP with only one interaction instead of the 50 EXP it would receive on a normal day.
Interaction Points are the same. Interacting with an Egg gives 6 Interaction Points on normal days, on a Bonus Day where 7 Interaction Points are added to each click an Interaction with an Egg gives 13 Interaction Points. On such a day a Pokérus Host gets the doubled amount, earning 26 Interaction Points for each Interaction with an Egg.