Table 3 Univariate analysis (chi-square) of herd and environmental potential risk factors (location, type of herd, presence of other ruminants, farm dimension, annual mean temperature, altitude, annual rainwater, distance from the coast) for Schmallenberg virus seropositivity

Total

812

329

40.5

37.1–43.9

Location

 Avellino

114

43

37.7

28.8–46.6

 Benevento

99

48

48.5

38.6–58.3

3.77

0.299

 Caserta

298

114

38.2

32.7–43.8

 Salerno

301

124

41.2

35.6–46.8

Type

 Fully stallfed

695

290

41.7

38.1–45.4

2.9

0.087

 Partly grazed

117

39

33.3

24.8–41.9

Presence of other ruminants

 Yes

211

86

40.8

34.1–47.4

0.007

0.93

 No

601

243

40.4

36.5–44.7

Farm dimension (number heifers)

 < 100

202

73

36.1

29.5–42.8

2.14

0.114

 > 100

610

256

41.2

38-45.9

Mean annual t°

 ≤ 16 °C

424

150

35.3

30.8–39.9

9.72

0.002

 > 16 °C

388

179

46.1

41.2–51.1

Altitude (a.s.l.)

 ≤ 250 m

483

211

43.7

39.3–48.1

4.96

0.026

 > 250 m

329

118

35.9

30.7–41

Annual rainwater (cm)

 ≤ 1000

214

86

40.2

33.6–46.8

0.013

0.909

 > 1000

598

243

40.6

36.7–44.6

Distance from the coast

 ≤ 20 km

302

140

46.4

40.7–52

6.8

0.009

 > 20 km

510

189

37.1

32.9–41.2