The Infectivity describes, how easily a pathogen can be transmitted from one infected person to another. It is a measure of the infectiousness of a pathogen.
Important points:
- The higher the infectivity, the easier it is for a pathogen to spread in the population.
- Difference to Risk of infection:
- Infectivity = Property of the pathogen (how infectious it is)
- Risk of infection = Probability for a particular person to become infected (also depends on behaviour and protective measures).
Examples:
- Measles viruses have a Very high infectivity - Even short contacts can be sufficient.
- HIV is in comparison less infectious - Transmission requires direct contact with infectious body fluids.
