Experiences after Twenty Months with Pandemic Influenza A (H1N1) 2009 Infection in the Naïve Norwegian Pig Population

Table 1

Surveillance programme for SI in Norwegian pigs in 2009 and 2010. Detection of pandemic (H1N1) 2009 specific antibodies by ELISA in different counties in Norway.

County	2009		2010
	Number of; herds tested	Number of; seropositive herds (%)	Number of; herds tested	Number of; seropositive herds (%)
Troms and Finnmark	5	0 (0%)	5	2 (40%)
Nordland	20	0 (0%)	20	4 (20%)
Trøndelag and Møre	88	3 (3%)	88	48 (55%)
Vestlandet	11	0 (0%)	24	5 (21%)
Rogaland and Agder	117	11 (9%)	129	73 (57%)
Vestfold, Buskerud, Telemark	62	1 (2%)	59	20 (34%)
Østfold and Akershus	77	0 (0%)	69	20 (29%)
Hedmark and Oppland	72	1 (1%)	65	18 (28%)
Total Norway	452	16 (3.5%); (95% CI 2.2–5.7%)	459	190 (41%); (95% CI 37–46%)