S. suis serotype 2 meningitis in a patient with horse contact in a Japanese stable: A case report

Streptococcus suis is a Gram-positive zoonotic pathogen primarily associated with pigs, but its potential transmission from other animals remains unclear. We report a case of S. suis serotype 2 meningitis in a 56-year-old Filipino stable worker with no known contact with pigs but a history of direct exposure to horses. He presented with fever and persistent headache following a head injury sustained one month prior. Cerebrospinal fluid (CSF) analysis revealed bacterial meningitis, and blood and CSF cultures identified S. suis serotype 2. Despite appropriate antibiotic therapy, the patient developed a brain abscess requiring craniotomy and experienced prolonged disorientation. This is the first reported case of S. suis meningitis suspected to have originated from a horse, highlighting the need for further epidemiological studies on non-porcine sources of S. suis infection.