If you have done nothing about them on your potatoes you probably do not have leaves anymore. Remember, potatoes can take quite a bit of defoliation without yield reduction, and you do want to leave Bt susceptible individuals out there to breed and keep their genes around. On the other hand, keep scouting your fields and if large populations of young larvae develop do not let them get out of hand. Cucumber beetle numbers are currently low in most fields with crops of all ages. However, bacterial wilt symptoms are showing up in many vine crops.
Leaves often look scorched and blighted, either along the margin or in the interveinal regions.
These symptoms have been observed in pumpkin, cucumber, summer squash and zucchini. These bacterial wilt infections came from cucumber beetle feeding on plants at the seedling stage. Once plants have 5 leaves, and are vining, flowering, and developing fruit it is unlikely that they will acquire damaging new infections. The most critical period for new infections with bacterial wilt from cucumber beetle is from the cotyledon to the 2 leaf stage. After the 3-4 leaf stage, beetle feeding is less likely to cause plants to wilt or develop other symptoms.