I wasn't expecting much when I picked this up, but was pleasantly surprised.
Definitely has that 1950s feel about it, but the story kept moving with a few twists along the way.
Characters were a bit wooden.

Apparently the original title was "Highways in Hiding" which is more apt.

Presumably for marketing at the time "Space Plague" was preferred even if a bit misleading.
As was the inside blurb: "Cause: Unknown - except for one thing - it came from outer space. It was spread by unknown, deadly beings whose sole aim was to keep it spreading - UNTIL ALL THE WORLD WAS IN THEIR POWER!"

It's actually more like a good old fashioned detective / action novel than a space drama. ( )

Written in 1955 it's a good hide-and-seek adventure story with minimal high-tech. A strange, horribly deadly, disease turns out to have very definite benefits which the bad guys don't want to share--but the good guys are too afraid of being misunderstood to want to try to share. ( )