Risk factors for porcine reproductive and respiratory syndrome virus infection and resulting challenges for effective disease surveillance

Table 5 The probability that farms infected with PRRSV will be detected through passive disease surveillance assuming 35% herd prevalence considering all farms and farms in individual risk strata

	Probability of detection of infected farm			Percentiles
	n	EPI*	Mode	5^th	95^th
All farms	2962	-	0.074	0.067	0.083
HDA* + live vaccine	303	1.000	0.069	0.054	0.084
HDA + no live vaccine	538	0.307	0.091	0.074	0.106
LDA* + live vaccine	765	0.425	0.068	0.053	0.084
LDA + no live vaccine	1356	0.113	0.089	0.074	0.106

The probabilities are shown as proportions.
*HDA=high pig density area, LDA=low pig density area, EPI=effective probability of infection.

ISSN: 1746-6148