Quote Originally Posted by kalinka_vinnie
- И кто из мальчонков навку таку увидит - тот с ума сходит зараз, и ходит, воит, стонет, пока в болото не прыгнет, шоб страх свой похоронить, вона как!
- And those of the guys who sees such a navka, he will go nuts due to the disease and he goes around, howling and moaning, until he jumps into the swamp, to bury his fear, that's how it is, see!
One other small correction (didn't see this the first time): I believe, "зараз"="сразу"="at once", it does not refer to a disease here.

Another (remote) possibility would be "now", which is "зараз" (stressed on the first A) in Ukrainian and so might also appear in some Russian dialects. Here it would mean smth like "right now there is a guy to whom this is happening", but it would look kinda unusual here given the rest of the sentence so I think Gerty meant "at once".