There are monks in India, they canot bath themselves, only hands and feet. They believe, the bath can kill millions of microorganisms.
Do you know that human body is a home for more than 1000 species of bacteria? And you have more germs on/in you than there are people on the earth? We are a pacific house for about 90 trillion of microbes. They live on the tongue, teeth and in all other places. Viruses like herpes sleep inside our nerve cells. Even about 8% of our DNA is made of parts of self-replicated viruses.
They have to survive living with us and have their strategies to remain with us even if we use antibacterial soap. It's known that overly hygienic environment increasis risks of different diseases. Because there are good bacteria like Lactobacillus acidophilus and bad bacteria like dental streptococcus that is dominant specie in the dental plaque. (and those last like to eat sugars!). In the follicles of our eyelashes lives demodex mites that makes sporadic walks in the nighttime around our face. We can have more than 100 types of human papillomavirus that can cause cancer. At least 500 species of bacteria that live in our gut make for us our essential nutrients and crowd out harmful bacteria. Other bacteria from Lactobacillus family that live in vagina protect us from Candida albicans.
So we have very great number of good microorganisms and relatively little number of bad bacteria. That ia why the good can beat those bad, normally.
The last notice is for those who doesn't love herpes. There are at least 2 viruses from this family that -if you are infected- can protect you from different bacterial infections.
Some days ago I read a notice, scientists found an alive bacteria about 500 000 years old and they want to know now how it does to live so long.