Hi, Jerry. I'm sure that your mold (probably) or fungus enjoyed the meal that you gave them and are growing better now. The latex paint was probably a real treat for them.
What you should have done is first kill the mold by washing with chlorine bleach and then keep them from returning by sealing the wall so that water cannot seep through. The next step should have been to check outside during a rain to see if water is puddling close to this area and divert the water away.
Since it is too late to do it the easy way, I think that your best bet is to scrape the basement walls in the area where the mold was growing and then redo it the right way. Get the walls down to bare concrete if possible and use one of the special basement wall paints that gets into the pores of the wall to block the water from penetrating. You can also add a fungicide (available from paint stores) to this paint.
Some people might try to tell you that exterior basement waterproofing or a basement drainage system is necessary and they might be, but they are big bucks. So try this first and be sure to get any water off the roof at least 6 feet away from the basement walls and have the dirt around the walls sloping away from the house for this same distance.