Human Streptococcus suis Infections, South America, 1995-2024

Streptococcus suis, a swine pathogen that causes zoonotic infections in Europe and Asia, has increasingly been observed in South America. We reviewed all available reports from the continent and identified S. suis cases in Argentina, Brazil, Chile, French Guiana, and Uruguay. We also identified 8 novel infections from Argentina, bringing the total documented human cases in South America to 47. We reclassified 1 previously reported infection as S. parasuis. Among the 47 S. suis cases, 40 (85%) patients had meningitis, 2 (4%) had toxic shock-like illness, 2 (4%) had nonshock sepsis, 1 (2%) had arthritis, and 1 (2%) had endocarditis. The case-fatality rate was 4% (2/47). Infections were primarily linked to pig or pork exposure, although some occurred after consuming undercooked meat. Case distribution varied by country, and Argentina reported a disproportionately high number of cases despite a smaller swine industry. Our findings highlight the need for more consistent regional S. suis surveillance.