The methods by which pathogens spread to cause INFECTION. Common transmission modes include
- airborne, in which pathogens enter the respiratory tract as particles suspended in the air
- sexual, in which pathogens enter the body through sexual contact
- direct contact, in which pathogens enter the body via touch
- foodborne, in which consumed foods contain pathogens
- waterborne, in which consumed water and foods prepared in that water contain pathogens
- bloodborne, in which pathogens enter the blood circulation through BLOOD TRANSFUSION or contaminated needles
Many infectious agents have multiple transmission modes. The common cold, for example, spreads through direct contact with nasal secretions as well as via airborne droplets.