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A case is described of a 79-year-old man, trampled by his horses, who subsequently developed a wound infection and, later, meningitis. Streptococcus equi subsp. zooepidemicus was isolated as the causative organism. S. equi subsp. zooepidemicus, which carries the Lancefield Group C antigen, is an uncommon human pathogen but is commonly isolated from bacterial infections in animals, particularly horses. It is most commonly acquired by humans following animal contact. A review of the literature identified 20 previously described cases of S. equi subsp. zooepidemicus meningitis. Crude mortality following infection was 24%. All of the patients who died were over 70 years of age and the ingestion of unpasteurised dairy products was associated with all but one of the fatal cases. Hearing loss was a frequent complication, occurring in 19% of cases. Only 38% of patients made a complete recovery. Treatment regimes commonly included benzylpenicillin or a third-generation cephalosporin, with a mean treatment duration in survivors of 23 days.

The records of cerebrospinal fluid (CSF) examinations for the three-year period ending 30 September 1991 were studied retrospectively. From 3,161 examinations, 66 pathogens were detected, 64 of which were from primary agar plate culture. Enrichment broth culture yielded 219 isolates of which 217 were likely contaminants. Only two pathogens were isolated by enrichment, and in both samples the CSF leucocyte counts were abnormal. The use of enrichment broth culture should be confined to CSF specimens with abnormal leucocyte counts and/or Gram stains.