First detection of porcine circovirus 4 (PCV-4) in Europe

Table 1 Wild boar and domestic pig samples tested by qPCR/PCR methods for the detection of PCV-4 in Spain and Italy. Percentage of qPCR/PCR positive ones are given attending to the type of sample and/or clinical condition studied

Country	Time period	Suidae species tested	Tested sample or clinical condition	Number of studied samples	Number of positive samples (%)
Spain	2011–2015	Wild boar*	Lymph nodes	166	56 (33.7%)
			Serum¹	90	8 (8.9%)
	2021–2023	Iberian pig*	Digestive²	99	7 (7%)
			Lung	57	2 (3.5%)
			Reproductive³	14	0 (0%)
			Others⁴	53	0 (0%)
	2018–2021	Commercial breed pig**	Digestive²	73	0 (0%)
			Lung	32	0 (0%)
			Reproductive²	66	0 (0%)
			Others⁴	13	0 (0%)
	1998–2020	Commercial breed pig**	PDNS cases⁵	100	0 (0%)
	2018–2020	Commercial breed pig**	Serum⁶	900	0 (0%)
Italy	2014–2015	Wild boar	Serum	187	0 (0%)
	2017–2018	Wild boar	Serum	29	0 (0%)
	2021–2022	Wild boar	Lung and lymph node homogenate	103	0 (0%)
		Commercial breed pig	Serum	45	0 (0%)
		Backyard pigs	Lung and lymph node homogenate	68	0 (0%)

*Samples from animals located in Mid-South-Western Spain; **Samples from animals located in North-Eastern Spain
¹The 90 sera from Spanish wild boar belonged to the 166 ones from which lymph nodes were tested
²Digestive samples included intestines, feces and rectal swabs
³Reproductive samples included foetus homogenates, placenta and fetus stomach content
⁴Others included sera and oral fluids from monitoring analytics, joint swabs from poliarthritis illness and organs such as liver, spleen or brain from systemic disorders and sudden deaths
⁵Mixture of tissues (lymph nodes, tonsil, spleen and lung) of porcine dermatitis and nephropathy syndrome (PDNS) affected pigs
⁶Serum of 3 day-old healthy piglets

ISSN: 1743-422X