In Article <3ducgo$ch6 at brachio.zrz.TU-Berlin.DE>
joaccigh at w203zrz.zrz.tu-berlin.de (Joachim Dagg) writes:
> Faulkner uses pathogenic and virulent as relative
>terms, but he couldn't quite point out, why they are not synonymous in
>his conception (at least he couldn't make it clear to me).
As I mentioned in an earlier post, according to its use in
epidemiology pathogenicity is an expression of the proportion of infections
with an etiologic agent which result in clinical disease, virulence refers to
the proportion of clinical cases which result in serious manifestations.
Because of the ambiguity inherent in "serious manifestations" I think there has
been a tendancy to use the Case Fatality Rate, or the number of clinical cases
who die as the result of infection as a quantitative estimate of virulence.
The distiniction between the two terms is based on the population they are
intended to describe. Pathogenicity describes the total population of infected
hosts, virulence describes the total population of clinical cases arising from
infection with the etiologic agent.
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* Charles T. Faulkner * When you don't know where you're
* Univ of Tennessee, Knoxville * going any road will take you there.
* (ctfaulkn at utkvx.utk.edu) * Alice
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