Diseases that spread from one person to another are called

• The traditional epidemiologic triad model holds that infectious diseases result from the interaction of agent, host, and environment.
• More specifically, transmission occurs when the agent leaves its reservoir or host through a portal of exit, is conveyed by some mode of transmission, and enters through an appropriate portal of entry to infect a susceptible host.

• An infectious agent may be transmitted from its natural reservoir to a susceptible host in different ways.
• There are different classifications for modes of transmission.
• Diseases can be transmitted directly or indirectly.

Image Source: Indian Journal of Health Sciences and Biomedical Research KLEU and Pinterest

Direct Transmission

• Direct transmission is the immediate transfer of the infectious agent from an infected host or reservoir to an appropriate entry point through which human infection can take place.
• This may be by direct contact such as touching, kissing or sexual intercourse, or by the direct spread of droplets by sneezing or coughing.
• Blood transfusions and tra
  how disease is spread by personal contact
  how disease is spread by soiled bath towels