Critical community size
Appearance
The critical community size (CCS) is the minimum size of a closed population within which a human-to-human, non-zoonotic pathogen can persist indefinitely.[1]
When the size of the closed population falls below the critical community size level, the low density of infected hosts causes extinction of the pathogen.[2] This epidemiologic phenomenon was first identified during measles outbreaks in the 1950s.[1]
The critical community size depends on:[citation needed]
- Speed of transmission
- How long until a person who has recovered remains immune
- Fatality rate
- Birth and death rate in the general population
See also
[edit]- Compartmental models in epidemiology – Type of mathematical model used for infectious diseases
- Epidemiology – Study of health and disease within a population
- Force of infection – Rate at which susceptible individuals acquire an infectious disease
- Mathematical modelling of infectious disease – Using mathematical models to understand infectious disease transmission
- Transmission risks and rates
References
[edit]- ^ a b Bartlett, M. S. (1960). "The critical community size for measles in the United States". Journal of the Royal Statistical Society. Series A (General). 123 (1): 37–44. doi:10.2307/2343186. JSTOR 2343186.
- ^ Haydon, Daniel T; Cleaveland, Sarah; Taylor, Louise H; Laurenson, M Karen (2002). "Identifying reservoirs of infection: a conceptual and practical challenge". Emerging Infectious Diseases. 8 (12): 1468–1473. doi:10.3201/eid0812.010317. PMC 2738515. PMID 12498665.
External links
[edit]- The Collection of Biostatistics Research Archive
- 'Epidemiology' – In: Philip S. Brachman, Medical Microbiology (fourth edition), US National Center for Biotechnology Information
- Monash Virtual Laboratory - Simulations of epidemic spread across a landscape
- People's Epidemiology Library