The Wellington Wells Health Institute is a large hospital-like building in the Parade District, where numerous Plague Victims are being imprisoned and experimented on by Joy Doctors. The Institute is run by Director Doctor Harold Ridgwell.
On the 9th of October, an anonymous doctor writes to the Exectuive Committee about giving them more funds for studying Coconut Joy, wishing that they also get test subjects other than Plague Wastrels. And that they should seek for an alternative just in case Verloc's "Permanent Solution" doesn't work out like he hopes it will.
On the 25th of October, 1964 at 3:30 Am. Arthur infiltrates the building in order to shut down the quarantine control so that he can cross Britannia Bridge. Right as he's about to do so, he gets ambushed by two Doctors and is taken on a Coconut Joy trip, this doesn't go quite as right as a malfuntion occurs and an explosion erupts in the room with the two Doctors, freeing Arthur.
It is after this when Arthur shuts down the quarantine control and releases the captured Plague Wastrels from the institute, letting their disease spread across the Parade District. This can be noticed when playing as Ollie Starkey.