Recently everyone has been concerned about the spreading of life-threatening viruses.   Talking about viruses makes everyone very nervous.   Everyone wants to kill viruses,  but there can be side effects when we reduce the amount of existing viruses and bacteria.   It can cause us to be more prone to allergies.   People who rarely engage in activities outdoors,  can get sick easier because they are not often exposed to germs in the air.   We cannot definitively win the war between germs and humans.