Strain | Susceptibility (s) | Infectiousness (i) | Mean duration (d) | Ci |
---|
NY99 | 1.00 | 0.37 | 3.11 | 1.15 |
Spain/2007 | 1.00 | 0.19 | 2.49 | 0.47 |
Italy/2009 | 1.00 | 0.15 | 1.43 | 0.21 |
Italy/2008 | 0.88 | 0.09 | 2.09 | 0.17 |
- The competence index (Ci) reflects the relative number of infectious mosquitoes that could be derived from feeding on a particular bird species (in this case, house sparrows) infected by a given virus strain (in this case, four WNV strains: NY99, Spain/2007; Italy/2008 and Italy/2009). Ci is determined as the product of susceptibility (proportion of exposed birds that become infected), infectiousness (proportion of vectors that become infected per day) and transmissible viremia duration (number of days a bird maintains an infectious viremia).