Rethinking Group B Streptococcus: The Rise of Sequence Type 283 as a Foodborne Zoonotic Pathogen.

Area of Science:

• Microbiology
• Infectious Diseases
• Food Safety

Background:

• Streptococcus agalactiae sequence type 283 (ST283), or Group B Streptococcus (GBS), has emerged as a significant foodborne zoonotic pathogen.
• A major outbreak in Singapore in 2015 highlighted its potential to cause severe invasive infections in healthy adults, linked to raw freshwater fish consumption.
• Since 2015, ST283 outbreaks have been reported across Southeast Asia and China, with increasing international incidence.

Purpose of the Study:

• To review current knowledge on ST283 as an emerging zoonotic and foodborne threat.
• To summarize the epidemiology, transmission dynamics, pathogenesis, diagnosis, and treatment of ST283 infections.
• To identify research gaps and emphasize the need for enhanced surveillance and preventive strategies.

Main Methods:

• Literature review synthesizing existing research on GBS ST283.
• Analysis of epidemiological data from reported outbreaks and sporadic cases.
• Compilation of information on transmission pathways, clinical manifestations, and antimicrobial susceptibility.

Main Results:

• Raw freshwater fish consumption is the primary transmission route, but handling fish and human shedding/transmission are also implicated.
• ST283 causes severe invasive infections like meningitis, septic arthritis, and bacteremia.
• While generally susceptible to antibiotics, delayed diagnosis in resource-limited settings impedes effective response.

Conclusions:

• ST283 represents a growing zoonotic and foodborne risk, particularly in Southeast Asia.
• Strengthened surveillance, improved diagnostic capabilities, and targeted preventive measures are essential.
• Further research is needed to fully understand and mitigate the threat posed by this pathogen.