Christine Betlinski Posted 10 months ago Purell now, Bacteri-ell later? I agree with Melissa. There are definitely services antibacterials provide that keep plenty of us healthy everyday. Purell prevents the spreading of viruses, and I use it regularly throughout the winter to prevent sickness during exam time. Exposure to the right bacteria should happen early, as Melissa said, and regular outdoor activity should theoretically be enough to maintain the microbes, as well as introduce new ones, on and in the human body.