When the Apollo 11 astronauts arrived back on Earth, no-one knew whether they were contaminated with secret space viruses or not – so the astronauts stayed in an Airstream trailer under quarantine for three weeks.
When the three Apollo 11 astronauts splashed down (upside down, by the way), they had to put on Hazmat-like suits before they got into the waiting life raft. As soon as possible, and still wearing the suits, they moved into a quarantine trailer kept on board the recovery ship.
When I say a trailer, by the way, I mean an actual trailer: the Mobile Quarantine Facility was an Airstream trailer retrofitted by NASA to act as a containment unit. It had a little curtain in front of the window, and when President Nixon (the granny-hater) turned up to congratulate them he did so by peeking through that little window. You can see the picture above, and some video below. He keeps his distance pretty well, possibly because of theoretical space bugs.
For the next three weeks, if they wanted the astronauts to move around then they just lifted the trailer and put it someplace else. It went from the recovery vessel (the USS Hornet) to Pearl Harbor to Houston with the five occupants still inside.
Five? Well, once the three astronauts were in the unit they were joined by a flight surgeon, William Carpentier, and an engineer, John Hirasaki. Hirasaki had actually just read The Andromeda Strain, but apparently he didn’t take it too seriously.