What are the different ways by which microorganisms enter our body?

Microorganisms enter our body through various pathways that are described as follows:

1. Through broken skin: Skin abrasions, open scars, and wounds are an entry pathway for organisms to enter the skin surface and cause infection. This includes fungi that cause ringworm and Mycobacterium tetani.
2. Fecal-oral route: Microorganisms that reside in contaminated food and water enter the body by consumption through the fecal-oral route. Example: Cholera caused by ingestion of contaminated food and water.
3. Nasal pathway: Influenza caused by the air droplets containing Myxovirus influenzae or Pneumonia caused by inhaling Streptococcus pneumoniae.
4. Blood transfusion: AIDS, Hepatitis B/C are caused when a healthy person is infected by the transfusion of contaminated blood from patients suffering from AIDS or Hepatitis B/C.