There are several primary transmission pathways:
1. Direct Contact Transmission: This occurs when there is physical contact between an infected individual and a susceptible host, leading to the transfer of pathogens. Examples include touching, kissing, and sexual contact.
2. Indirect Contact Transmission: This involves the transfer of infectious agents through contaminated objects or surfaces, known as fomites. Examples include doorknobs, utensils, and medical equipment.
3. Droplet Transmission: Infectious agents are spread through respiratory droplets expelled when an infected person coughs, sneezes, or talks. These droplets can land on mucosal surfaces of a nearby person's mouth, nose, or eyes.
4. Airborne Transmission: Pathogens are carried by dust or droplet nuclei suspended in the air over long distances and time. Diseases such as tuberculosis and measles are known to spread this way.
5. Vector-Borne Transmission: This occurs when vectors, such as mosquitoes, ticks, or fleas, transmit pathogens from one host to another. Malaria and Lyme disease are classic examples.
6. Vehicle Transmission: This involves pathogens being transmitted through contaminated mediums such as water, food, or air. Cholera, for instance, is spread through contaminated water.
