I use a fork to remove the berries from the strigs. Hold the stem at the thick end and pull down. Any bugs are removed that way too. It doesn't take long. I do not wash the currants. I haven't made jelly for years but when I did I just used the old pound of sugar to a pint of juice formula. These days we eat our red currants as red currant short bread or summer pudding.

Ps strigs is not a misspelling.

I wouldn't wash, nor worry about the bugs. Just strain the juice through cheesecloth or a jelly bag or coffee filters. The bugs won't make it through.