Table 2.

Parameter estimates by the MCMC method.

		Parameter estimates
Parameter	Definition	Median	95% credibility interval
βw(d-1)	Direct transmission rate	0.15	(0.03; 0.31)
βE(w) (g ge-1d-1)	Within-pen Environmental transmission	2 · 10-6	(1 · 10-7; 7 · 10-6)
βE(b) (g ge-1d-1)	Between-pen Environmental transmission	7 · 10-8	(5 · 10-9; 3 · 10-7)
A	Shape parameter§	5.3	(3.2; 8.7)
B	Rate parameter§	0.76	(0.48; 1.25)
δ(d-1)	Clearance rate	0.33	(0.19; 0.46)

β_w is the direct transmission rate, defined as the mean number of newly infected pigs generated by a single infectious individual in a fully susceptible population per time unit. ${\beta }_E^{\left(w\right)}$, ${\beta }_E^{\left(b\right)}$ represents the within- and between-pen transmission rates related to the environmental component, defined as the mean number of newly infected pigs per viral particle per gram of feces in the environment (see text for more details).

^§A and B are respectively the shape and rate parameters of the gamma distribution assumed for the latency duration in contact animals (probability density function (f_Lat (t, A, B)).