I too am having a huge infestation of both the spotted and striped cucurbit beetles. We originally thought that the white powdery stuff on the leaves was a result in the spray miracle grow we were using (never used before) until we noticed most of our pumpkins that were newly growing and ranged from 2 inches round to 6 inches round where shriveling up and dying. Then we went out in early evening to be swarmed with these beetles! so when I looked it up I seen what the white stuff was and the culprit!
I'm not one to use harmful pesticides! Not only is it not good for us the environment and bugs that provide a positive impact on the home garden but I have a dog that thinks she's human and likes to try snoop about the pumpkins when we do (as if helping). I did find a home solution that can be made for the adult beetles with ingredients everyone may have in their pantry. in a mason or old pickle jar take 1 cup boiling water and pour over 3 cloves garlic I crush them, 2 table spoons of red pepper flakes. allow to sit over night then add 1 qt water and 2 table spoons of dish soap. pour solution in a spray bottle and go to town getting tops and bottoms of leaves. to help treat the bacteria mix 2 tblsp of baking soda with 2 qts of water spray anywhere the white bacteria is ie: leaves and stems. I have read to help keep new arrivals and to keep the bacteria from spreading to the pumpkins and cucumbers you must cut off all the leaves that are infected place in a plastic bag seal and throw away. If I do that I will have 5 leaves left out of 6 pumpkin vines :( I am praying that our 5 pumpkins we have so far will be spared. I havent noticed damage to our cucumbers and watermelons until this morning! Hope it helps!

Cucumber beetles, and the Squash Vine Borer, can be real problems for those growing any memeber of the cucurbit family, as can Powdery Mildew, the white stuff on the leaves usually.
The ghorganics web site does provide some good information if you can get by the link about pyrethrine right away.
Powdery Mildew is a fungal disease rather then bacterial.
http://attra.ncat.org/attra-pub/bakingsoda.html

Here is a link that might be useful: About Cucumber Beetles

I got some volunteer help this season on cucumber beetles. they had just started to worry me when a colony of yellow jackets found them and wiped them out in no time. Fortunately the yellow jackets have their nest somewhere other than my garden so I get their help without worrying about getting stung.

For some of us the discovery tht Yellow Jackets are predators of other, more harmful, insects is not news. We have known that for years and have tried often to tell others.
A major part of Integrated Pest Manangement is learning which insects are really the bad guys and which are beneficial and what each one does. For example, some stink bugs are actually predators of other, more harmful, insects so simply the presence of stink bugs in a garden is not necessarily a sign of a problem that needs some kind of potent spray. Spraying many of the poisons available will kill off the beneficial insects that could help you control the few pests you might have in your garden.

The kissing bug is a good example of a beneficial stink bug that preys on other insects but they have a bad habit of giving the gardener an occasional kiss too. OUCH! Talk about tough love. :D