Table 1.

Attributes of flocks studied and environmental conditions at sampling events.

Farm ID	French depart.a	Specie/type	House	Flock initial size	House poultry densityb	Positive confirmation datec (dd/mm/yyyy)	Proportion of positive poolsd	Clinical signs	Air sampling date (dd/mm/yyyy)	Sampling location/distance (m)	Ambient temperature (°C)	Wind velocity (km/h)
A	40	Ducks/PAGe	Tunnelf	2,500	7/m2	29/01/2017	2/2	Mortality/symptoms	31/01/2017	Inside	NR	<5
											NR
										External exhaust fans	NR
											20
										Outside 5 m
										Downwind 50 m
B	64	Ducks/PAG	Tunnel	3,000	0.5/m2	09/03/2017	5/24	None	16/03/2017	Inside	NR	10
											NR
										External exhaust fans	NR
										Outside 5 m	24
										Downwind 80 m
4	64	Ducks/FFG	Barn	800	2.5/m2	11/03/2017	12/12	None	16/03/2017	Inside	NR	<5
											NR
										External exhaust fans	NR
										Outside 5 m	17
										Downwind 60 m
D	40	Chickens/grow	Barn	4,000	1/m2	14/03/2017	2/2	Mortality/symptoms	21/03/2017	Inside	NR	<5
											NR
										External exhaust fans	NR
											12
										Outside 5 m
										Downwind 50 m
E	64	Chickens/grow	Barn	4,400	8/m2	18/03/2017	8/8	Mortality/symptoms	22/03/2017	Inside	NR	≈0
										Loading for culling	NR
											2
										Downwind 110 m

^aDepartment is an administrative division unit in France (the median land area of French metropolitan departments is 5,960 km²).

^bAt sampling event.

^cDate of the official sampling that permitted to confirm the avian influenza H5 infection of the flock.

^dProportion of pools of five swabs (cloacal or oropharyngeal) positive to rRT-PCR targeting the matrix gene at the official sampling.

^ePAG, growing ducks for “foie gras” production.

^fTunnel: open sided tunnel.

^gFF (“foie gras” production).

NR, not recorded; FF, force feeding period; PAG, prêts à gaver.