Streptococcal infection in young pigs. IV. An outbreak of streptococcal meningitis in weaned pigs.

Twenty-eight pigs died in an outbreak of streptococcal meningitis in an East Anglian herd. Most were 10-14 weeks old. The outbreak lasted from January to April and was finally controlled by antibiotic therapy. A similar number of losses had occurred in the previous year though no diagnosis had then been made. The causal agent appeared to be a haemolytic streptococcus belonging to group D and provisionally designated Streptococcus suis type 2. It is probably identical with de Moor's group R streptococcus which causes a similar disease in the Netherlands. It is serologically distinct from Streptococcus suis type 1 which causes meningitis in piglets. Type 2 infection in pigs appears to be widespread in England and Wales and to occur in animals up to the age of at least 14 weeks. A comparison is drawn between Str. suis meningitis in pigs and group B streptococcal meningitis in human infants.