Update VB_intro_to_traits.qmd

Author: catlippi

VB_intro_to_traits.qmd

@@ -163,16 +163,19 @@ $\Rightarrow$  questing, host/food preference, thermal regulation, site selectio
 
 <center>
 ![](graphics/intro_traits_13.jpg)
-</center>                       
+</center>      
 
+## SIR Model
+<center>
+![](graphics/SIR_1.jpg)
+</center>
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 We can get more complex/realistic models...
 
 <center>
 ![](graphics/SIR_2.jpg)
 </center>
-
 H=host, V=vector, $_S$=susceptible, $_I$=infected, $_R$=recovered
 
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@@ -182,17 +185,14 @@ But with every parameter added, more data are needed!
 <center>
 ![](graphics/SIR_3.jpg)
 </center>
-
 H=host, V=vector, $_S$=susceptible, $_I$=infected, $_R$=recovered
 a=biting rate, b=vector to host transmission success (proportion of bites), d=recovery
 
 
 -----------------------------------------------------------------------
-
 <center>
 ![](graphics/SIR_4.jpg)
 </center>
-
 H=host, V=vector, $_S$=susceptible, $_I$=infected, $_R$=recovered
 a=biting rate, b=vector to host transmission success (proportion of bites), d=recovery,
 c=host to vector transmission success (proportion of bites), P=extrinsic incubation period,