The net and basic reproduction numbers are among the most widely-applied concepts in infectious disease epidemiology.
A net reproduction number (the average number of secondary infectious cases resulting from each case in a given population) of above 1 is conventionally associated with an increase in incidence ; the basic reproduction number (defined analogously for a'totally susceptible'population) provides a standard measure of the'transmission potential'of an infection.
Using a model of the epidemiology of tuberculosis in England and Wales since 1900, we demonstrate that these measures are difficult to apply if disease can follow reinfection, and that they lose their conventional interpretations if important epidemiological parameters, such as the rate of contact between individuals, change over the time interval between successive cases in a chain of transmission (the serial interval).
The net reproduction number for tuberculosis in England and Wales appears to have been approximately 1 from 1900 until 1950, despite concurrent declines in morbidity and mortality rates, and it declined rapidly in the second half of this century.
The basic reproduction number declined from about 3 in 1900, reached 2 by 1950, and first fell below I in about 1960. (...)
Mots-clés Pascal : Homme, Tuberculose, Mycobactériose, Bactériose, Infection, Réinfection, Long terme, Epidémiologie, Analyse risque, Transmission homme homme, Modélisation, Modèle mathématique, Analyse statistique, Angleterre, Grande Bretagne, Royaume Uni, Europe
Mots-clés Pascal anglais : Human, Tuberculosis, Mycobacterial infection, Bacteriosis, Infection, Reinfection, Long term, Epidemiology, Risk analysis, Transmission from man to man, Modeling, Mathematical model, Statistical analysis, England, Great Britain, United Kingdom, Europe
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 99-0017570
Code Inist : 002A05B11. Création : 31/05/1999.