Invading the body

Most infections are communicable and can spread in different ways. For any disese to be passed on, the pathogen needs to get inside the body. They can get in through body openings or straight through the skin to the blood. They are transmitted in a variety of ways.

• Vectors.
• Fomites.
• Direct Contact.
• Inhalation.
• Ingestion.
• Inoculation.

Barriers to entry.

The skin forms a natural barrier that's toughened by keratin. In addition, sebum, which is produced by the skin, contains chemicals that inhibit the growth of microorganisms. Natural skin flora successfully compete for poition on the skin against pathogens and sometimes produce substances that inhibit the growth of the pathogens. The surface of internal tubes and ducts are mmore vunerable as they…