cucumber bacterial wilt
How to avoid cucumber bacterial wilt on newly planted cucumber plants
That disease is spread by cucumber beetles. Here are the strategies you can use, from our Grow It Eat It section, "Problems": http://extension.umd.edu/growit/insects/cucumber-beetles-spotted-or-striped
To keep young plants protected, row cover works well. Put soil or 2 X 4's laid flat over the row cover edges, so no beetles can get under the fabric.