Infectious disease

Slovak term: infekčná choroba

1. A clinically manifest disease resulting from an infection (WHO 2007).
2. An illness due to a specific infectious agent or its toxic products that arises through transmission of that agent or its products from an infected person, animal, or reservoir to a susceptible host, either directly or indirectly through an intermediate plant or animal host, vector, or the inanimate environment (Last 2001).
3. Any disease which can be transmitted from one individual to another by a causal agent which passes either directly or indirectly from the infected to the non-infected individual (Singelton and Sainsbury 2001).
4. Also referred to as : transmissible disease, contagious disease and communicable disease

Explanation

The term "infectivity" describes the ability of an organism to enter, survive and multiply in the host, while the "infectiousness" of a disease indicates the comparative ease with which the disease is transmitted to other hosts. An infection however, is not synonymous with infectious disease, as an infection may not cause important clinical symptoms or impair host function (WHO 2009).

Example

Many important infectious diseases (such as cholera, cryptosporidiosis, giardiasis, hepatitis A and E, listeriosis and typhoid fever) are transmitted by contaminated food and water.

References

• Last, J. (2001) A Dictionary of Epidemiology. 4th edition. Oxford University Press. New
• York, USA
• Singelton, P and Sainsbury, D. (2001) Dictionary of Microbiology and Molecular Biology.
• 3rd edition. John Wiley & Sons Ltd. London, UK
• WHO (2007) Foodborne disease outbreaks: Guidelines for investigation and control
• WHO (2009) Health impact assessment glossary: E-learning modules

Links

• WHO — The Health and Environment Lexicon