Mealybugs and the prevention of spread to other plants

[DesignerofBeauty]

Hello All,

I am wondering how to prevent mealybug infestation to other plants. I know to repot the infested orchid and spray the roots and entire plant with imidicloprid, three times at weekly intervals. I will also quarantine the plant. This is based on the information I have read on this forum.

Here's the question I have: I had a mealybug infestation on another plant a while back. It was my maxillaria scalariformis. I mixed a solution of 1 part 90% isopropyl alcohol to 1 part water. I also added a few drops of neem oil and dawn dish detergent. The treatment killed the plant. I threw it out and purchased another plant. I did not see any signs of infestation on any other plants. I thought I was in the clear.

Lo and behold this AM I found a stinker on my cattleya. I plan on treating the plant with imidicloprid this time. I haven't used a chemical pesticide like this before. I have two tiny dogs, must I spray outside? Or can I spray just in my shower?

To prevent infestation to my other plants, should I spray them as well? I'm afraid of killing them in the process and would rather use as little pesticide as needed. Should I spray my window area with isopropyl alcohol?

If anyone has any input, I would greatly appreciate it!