No abstract

The two commercial ELISA were more sensitive than the CFT in all panels from infected ruminants. However, they could only detect IgG. The I-ELISA should be the serological test method of choice for cattle, sheep and goats for import testing of animals into New Zealand because it was more sensitive than the P-ELISA and was equally specific to the PELISA and the CFT. For other animal species, such as deer and camelids, the CFT should still be used since none of the ELISA has been evaluated for these species. This study has shown that the two commercial ELISA will detect the majority of infected ruminants but may miss animals that have not developed an IgG response.

No abstract

Serum samples from pig herds in Great Britain have been examined for antibodies to influenza virus since 1968. Antibodies to H3N2 virus strains have been found since 1968 and the serological data presented here suggests that H3N2 virus strains continue to persist in the pig population. An outbreak of acute respiratory disease occurred in a 400-sow unit. The outbreak was characterised by coughing, anorexia, fever, inappetence and loss of condition. The gilts and weaners were affected and the morbidity approached 100 per cent. An influenza A virus designated A/Swine/Weybridge/117316/86 (H1N1) was isolated from the herd and 28 paired serum samples from the affected animals showed increases in the haemagglutination inhibition titres to this isolate. Haemagglutinin and neuraminidase characterisation indicated that the virus is similar to H1N1 viruses isolated recently from pigs in Europe. A total of 91 herds experiencing respiratory disease were investigated, of which 42 gave positive reactions in the haemagglutination inhibition test. Antibodies to A/Port Chalmers/1/73 (H3N2) were also detected in some of the herds but it is not known whether this strain plays any role in the current respiratory disease problems in pigs.

This study describes the isolation and characterization of an influenza virus subtype H3N2 designated A/Swine/Weybridge/163266/87 . The virus was isolated from a severe outbreak of respiratory disease in East Anglia . Haemagglutinin and neuraminidase characterization showed the virus to be very similar to H3N2 strains circulating in the human population during the years 1972-1975, and to H3N2 strains recently isolated from pigs in Belgium and France . A serological survey showed antibodies to the virus to be present in 31% of pigs tested, and reactors were detected on 43% of farms sampled .