Infections of all sorts can develop in any tissue anywhere in the body. An entire EM Level 3 handbook is dedicated to this subject so I will not dwell further on it here. However, review the Pathogen Protocol for more ideas on treating infections.
Other perspectives on this issue:
Different kinds of infectors can relate to different kinds of interactions and relationships with the people in your life. Fungus tends to grow in people who have friends who need constant attention but who do not reciprocate. These relationships often weaken and can even end as fungus is treated internally in the body. Bacteria and viruses often relate to some form of coercion, cajoling, manipulation or forcing a person to act against their will. Chronic infections are an indicator that this is an ongoing issue whereas acute infections likely follow a singular event.