Porcine respiratory coronavirus spread in Catalunya, Spain, a previously infection-free area

Seroprevalence of porcine respiratory coronavirus in selected Korean pigs

A total of 446 serum samples from 88 herds in Korea were examined for antibody to porcine respiratory coronavirus (PRCV) using blocking enzyme-linked immunosorbent assay (ELISA). All serum samples were collected from 24- to 26-week-old finishing pigs between December 1998 and June 1999. By ELISA, 237 out of 446 sera tested (53.1%) and 54 out of 88 sampled herds (61.3%) were positive against PRCV. Of 446 sera from 88 herd tested, 185 (41.5%) serum samples from 22 (25%) herds were seronegative against PRCV and transmissible gastroenteritis virus infection. Our data suggested that seropositive herds for PRCV are distributed diffusely throughout South Korea.

Seroprevalence of porcine epidemic diarrhea virus infection among different types of breeding swine farms in Spain

A cross-sectional study for determining the seroprevalence of porcine epidemic diarrhea virus (PEDV) infection among swine breeding farms in the Castilla y León region (Spain) was carried out. Breeding farms were stratified according to size and type of production (intensive or extensive). The number of farms to be sampled in each stratum was calculated from the latest census data available and the prevalence of seropositive farms obtained in other countries. Within each herd, the number of sows needed to detect the presence of the disease were sampled, according to within-herd seroprevalence data obtained by us in previous studies. A total of 5098 sow serum samples from 794 different farms were collected during 1992–1993 and tested for the presence of PEDV-specific antibodies, using a blocking ELISA with monoclonal antibodies; 55.9% of herds had at least one positive animal; 29.6% of sera were positive. Seropositive farms were detected throughout the sampled region, indicating that the infection was widespread. Higher farm-level prevalence rates were found in farms with more than 20 sows compared with small ones (≤ 20 sows) and in intensive than in extensive herds. On the other hand, within-farm seroprevalence and mean blocking percentage of positive sera decreased with increasing size of the farm.