What is pokerus on Pokemon Pearl?

You know, Pokerus can happen in any version. But anyway pokerus is a virus you can get very rarely from a wild Pokemon.( unfortunatly, you cant tell if the wild Pokemon has the pokerus.) Also you can heal your Pokemon alot of times. Its never happened to my Pokemon before but if you want more info. about it you can buy a Pokemon pearl/diamond guide. that's where I got the info.